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Ground Cherry

Physalis grisea
Also known as: Husk Cherry, Cape Gooseberry, Strawberry Tomato, Husk Tomato, Pineapple Tomatillo

Ground Cherry is a vegetable in the Solanaceae family. It grows best in full sun with medium moisture, and is listed for USDA zones 2-13. Plants reach harvest about 64–98 days after planting and sit about 12 inches apart.

Varieties

4 from High Mowing, True Leaf Market & Seeds Now · sorted by days to maturity
  • Goldie Ground Cherry64–86 days

    Florida weave or let sprawl; Bushy, spreading habit

    Sweet, tropical-tasting gold berries wrapped in paper husks. Bushy plants grow 2.5-3’ tall. When ripe, the husk around the fruit becomes papery dry and the fruit falls off the plant to be picked up from the ground. Some people place a tarp underneath the plants to make harvesting easier, but either way the husks keep the fruit clean. Physalis pruinosa

    Growing notes: Days to maturity are from transplant. Ground cherries (Physalis grisea) are warm-season tender annuals in the Solanaceae family, related to tomatillos. Start seeds indoors 6-8 weeks before the last frost and transplant after danger of frost has passed, when soil has warmed. Space plants 24-36 inches apart in full sun with well-drained soil. The low, sprawling, branching plants need little support; fruits ripen inside papery husks and are ready to harvest when the husks turn tan and the berries drop to the ground.

    View on High Mowing
  • Aunt Molly's65–70 days

    Heirloom; Vegetable; Annual

    Aunt Molly's Tomatillo Seeds. 65 - 70 days to maturity. Physalis pruinosa. Heirloom. Annual. Indeterminate. Very sweet tomatillo with an underlying tartness. These half to three quarter inch fruits are inside a papery husk and drop to the ground when ripe. Approximately 7,500 seeds per ounce.

    View on True Leaf Market
  • Ground Cherry72–98 days

    Can tolerate hot temperatures; Direct sow; Grows well in full sun; Grows well with containers; Grows well with raised beds; Matures in <90 days; Start indoors; Super easy to grow

    Ground cherry (Physalis pruinosa, also sold as P. grisea) produces small, golden, cherry-sized fruits about 1/2 to 3/4 inch across, each wrapped in its own papery husk. The fruits are sweet with a mild, tropical pineapple-tomato flavor and are eaten fresh, dried, or used in jams and pies - they are not the tart, 1-2 inch tomatillos used for salsa. The low, spreading plants drop their ripe husked fruits to the ground when ready.

    View on Seeds Now
  • Pineapple72–98 days

    Can tolerate hot temperatures; Direct sow; Grows well in full sun; Grows well with containers; Grows well with raised beds; Matures in <90 days; Start indoors; Super easy to grow

    Pineapple ground cherry (Physalis pruinosa) bears small golden fruits about 1/2 to 3/4 inch across, each in a papery husk, with a distinctive sweet, pineapple-like flavor. Eaten fresh, dried like raisins, or used in preserves and pies - not a tart salsa tomatillo. The low, spreading plants drop their ripe husk-wrapped fruits to the ground at maturity.

    View on Seeds Now
Family
Solanaceae
Category
Vegetable
Form
Bush
Lifecycle
annual
Zone
2-13
Height
1–3 ft
Spread
1.5–3 ft
Sun
Full sun

Plant spacing

1 plant per square footSquare-foot planting diagram: one ground cherry fills a 1-foot square, spaced 12 inches from its neighbors.
1 plant per square foot

In a square-foot bed, space ground cherry about 12 in apart — that fits 1 plant in each 1-foot square (1×1). Wider rows or containers space the same.

Water
Medium

Plan your ground cherry planting

Add ground cherry to a free GardenDraft plan and get sow, transplant, and harvest dates computed for your ZIP code — with a drag-and-drop bed layout and reminders when it’s time to plant.

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At a glance

Days to harvest
64–98 days
From transplant or sow to first harvest
Harvest style
Keep picking
Crops over several weeks
After harvest
Use within days
Quality eases off after peak
Frost tolerance
Tender · to ~32°F
Lowest temperature the foliage usually survives
Germination
~50%
Typical minimum germination rate

Storing & preserving

Most keep best refrigerated; storage crops prefer a cool, dry spot.

  • Freeze: Blanch briefly, cool, then freeze — keeps color and texture.
  • Can: Pressure-can low-acid vegetables; water-bath only pickled/acidified ones.

General home-preservation guidance — for tested processing times and safety, follow the National Center for Home Food Preservation.

Growing timeline

When to plant and harvest ground cherryPlanting timeline for ground cherry, relative to last frost: start indoors from 7 weeks before last frost to 1 week after last frost; grow from 1 week after last frost to 10 weeks after last frost; harvest from 10 weeks after last frost to 15 weeks after last frost.Start indoorsGrowHarvestLast frostTransplant
Start ground cherry indoors ~8 weeks before transplanting 1 week after last frost; first harvest 10 weeks after last frost.
Seed to transplant
42-56 days
Outdoor planting
7 to 14 days vs frost
Propagation
Seed
Schedule anchor
Last Frost

Companion planting — with cited sources

From US/Canada cooperative-extension publications and peer-reviewed studies. Evidence-tier dots show how strongly each recommendation is backed: ●●● peer-reviewed mechanism · ●● extension consensus · traditional knowledge with a plausible mechanism.

Pairs well with (24)

  • French MarigoldEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismpest-deter

    Tagetes patula releases alpha-terthienyl from roots, a thiophene with peer-reviewed nematicidal activity against root-knot nematode (Meloidogyne incognita and related species). T. patula also emits airborne limonene shown in PLOS One trials to deter glasshouse whitefly from tomato. Most reliable when grown as a solid cover the prior season, but interplanting still gives a partial benefit. Tagetes patula suppresses root-knot nematode populations on Solanaceae roots.

    Timing: Full-season marigold cover the prior year is the strongest single treatment.

    Region: Most valuable in zones 7+ and high tunnels with established root-knot nematode populations.

    Source: S1, UC IPM

  • AsparagusEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter

    Asparagus roots contain asparagine and associated compounds with reported activity against the root-knot nematode (Meloidogyne spp.), to which tomato is highly susceptible. Several extension sources (Cornell, Iowa State) endorse the tomato-asparagus pairing on this basis, though field-trial data are thin. Tomato is also said to repel asparagus beetle, but evidence for this is weaker.

    Timing: Plant tomatoes at one end of an asparagus bed where they won't shade the asparagus fern.

    Source: S1, S8

  • Bay LaurelEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter, flavor-folklore

    Bay laurel is sometimes interplanted in Mediterranean kitchen gardens; the essential oils (eucalyptol, linalool) have mild lab-demonstrated repellency against some stored-product insects, but field evidence for tomato pest deterrence is absent. Tier C.

    Region: Mediterranean climate gardens (CA).

    Source: UC IPM

  • Bee BalmEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Monarda didyma flowers attract bees, hummingbirds, and parasitic wasps that prey on tomato hornworm; recommended as a perennial bed-edge companion in Cornell and Penn State home-garden guides. Susceptible to powdery mildew — choose resistant cultivars.

    Region: Eastern North America native; thrives zones 4-9.

    Source: S1, Penn State Extension

  • BorageEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Borage (Borago officinalis) attracts bumblebees and other pollinators that buzz-pollinate tomato flowers, and attracts predatory insects (lacewing, syrphid) that help suppress tomato pests. Documented in UMN and Cornell home-garden guides; field-trial evidence specific to yield effect is limited.

    Source: S1, S7

  • BuckwheatEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Buckwheat strips between tomato beds host Syrphid flies and minute pirate bugs (Orius spp.) that prey on thrips and aphids. Used as an in-season insectary strip in Northeast organic tomato systems.

    Timing: Stagger 2-3 sowings 2 weeks apart to keep continuous bloom.

    Source: S1, Penn State Extension, SARE

  • CarrotEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationflavor-folklore

    Carrot / tomato is a long-standing folk pairing without a clearly replicated mechanism. The crops have non-overlapping rooting depths and tomato canopy can provide light shade during midsummer heat. Tier C with flavor-folklore tag.

    Source: University of Maryland Extension

  • CilantroEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpredator-attract, pollinator-attract

    Flowering cilantro is documented to elevate natural-enemy abundance (syrphids, lacewings, parasitoids) in tomato beds, contributing to aphid and hornworm suppression.

    Source: S1, S5

  • Common BeanEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationn-fixation

    Bush bean interplanting between tomato plants contributes modest residual N from nodule turnover and post-season residue. Effect on same-season tomato yield is small; primarily helps the following crop.

    Source: University of Maryland Extension

  • Common CeleryEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationflavor-folklore

    Celery / tomato is a long-standing folk pairing with no replicated mechanism beyond shared cultural requirements (full sun, steady moisture, rich soil). Included for completeness; tier C with flavor-folklore tag.

    Source: University of Maryland Extension

  • Common ChivesEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter

    Chive perimeter or interplant is widely cited by extension references as deterring aphids on tomato; effect is plausible (volatile masking) but field-trial evidence is thin.

    Source: University of Maryland Extension, S13

  • Common NasturtiumEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationtrap-crop, pollinator-attract

    Nasturtium near tomato is traditionally recommended for aphid trapping and pollinator support; pollinator benefit is well-supported, aphid trap-cropping in tomato is less studied than in cucurbits/beans.

    Source: University of Maryland Extension

  • Common ParsleyEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpredator-attract, pollinator-attract

    Allowed-to-bolt parsley provides accessible nectar for syrphid flies, lacewings, and small parasitoid wasps that suppress aphids and hornworm eggs in tomato. The pairing is a long-standing extension home-garden recommendation; mechanism is plausible, replication is modest.

    Timing: Best benefit comes when second-year (biennial) plants flower or when first-year plants are allowed to bolt.

    Source: University of Maryland Extension, S13

  • Common ThymeEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Thyme in flower supports parasitoids of tomato hornworm and aphids; bed-edge planting is a common recommendation.

    Source: University of Maryland Extension

  • DillEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpredator-attract

    Young dill is reported by extension home-garden guides to attract Trichogramma wasps and other natural enemies of tomato hornworm. Many guides also recommend removing dill before it bolts because mature dill is reported to suppress tomato vigor.

    Timing: Use as a young-plant companion; remove before flowering to avoid reported tomato growth suppression.

    Source: University of Maryland Extension

  • Greek Bush BasilEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter

    Shares Ocimum basilicum volatile profile; same rationale and same evidence tier as sweet basil for tomato pest deterrence and bed-mate use.

    Source: University of Maryland Extension, Bekele & Hassanali, 2001

  • Holy BasilEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter, pollinator-attract

    Holy basil (tulsi) shares the linalool/eugenol-rich volatile profile of Ocimum basilicum and is heavily visited by bees; same general companion guidance.

    Source: University of Maryland Extension, Bekele & Hassanali, 2001

  • Italian ParsleyEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpredator-attract

    Same insectary role as common parsley; see common parsley for complete discussion.

    Source: University of Maryland Extension, S13

  • Lemon BalmEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Lemon balm supports parasitoid wasps and small predators that attack tomato hornworm and aphids; mechanism plausible but field replication limited.

    Source: University of Maryland Extension

  • Lemon VerbenaEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, flavor-folklore

    Lemon verbena is a common kitchen-garden herb companion. The citral-rich foliage is sometimes claimed to deter insects, but empirical support is weak; pollinator attraction during bloom is real. Mostly traditional practice with weak mechanism.

    Source: S11

  • Mexican Mint MarigoldEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpollinator-attract, predator-attract

    Tagetes lucida flowers attract bees and predatory insects; lacks the strong α-terthienyl nematicidal activity that distinguishes T. patula and T. erecta, but provides general insectary value.

    Source: S11

  • New Zealand SpinachEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationweed-suppression, moisture-conservation

    New Zealand spinach makes a heat-tolerant summer leafy green and is sometimes used as a living groundcover under widely spaced tomato trellises; it suppresses weeds and conserves moisture and is harvested through the heat of summer when true spinach has bolted. Mechanism plausible; specific replicated extension data limited.

    Source: S1

  • Pot MarigoldEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpredator-attract

    Calendula is recommended as an insectary plant in tomato rows; supports hoverflies and small parasitoid wasps that attack aphids and small caterpillars.

    Source: University of Maryland Extension

  • Sweet BasilEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationpest-deter, pollinator-attract, flavor-folklore

    Basil (Ocimum basilicum) leaf volatiles (eugenol, linalool, methyl chavicol) have laboratory-documented deterrent activity against thrips, aphids, and whiteflies, with limited but supportive field results from Iowa State, University of Minnesota, and West Virginia extension trials. Basil flowers also attract pollinators and parasitic wasps. Folk claims that basil improves tomato flavor are unverified and tagged separately. Long-standing folk claim that basil improves tomato flavor in the field. No empirical support, but listed honestly because the claim is too widespread to silently omit.

    Source: S7, Eliot Coleman, Bekele & Hassanali, 2001

Avoid planting near (39)

  • Black WalnutEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismallelopathy-negative

    Juglone produced by Juglans nigra roots, leaves and hulls causes wilt, stunting, and death in tomato. Effects extend roughly to the dripline and beyond. Iowa State, Michigan State, and University of Wisconsin extension all list tomato among the most sensitive vegetables. Standard mitigation is raised beds with root barriers and removal of walnut leaf litter.

    Region: Anywhere Juglans nigra is in the landscape: eastern and midwestern US, southern Canada.

    Source: S5, S8, S10

  • Common PotatoEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismdisease-host, alternate-host-pest

    Tomato and potato share late blight (Phytophthora infestans) and serve as alternate hosts for each other's pathogen spores; they also share Colorado potato beetle, early blight (Alternaria), and Verticillium wilt. UMN Extension explicitly recommends not planting tomatoes where tomatoes, potatoes, peppers, or eggplants have been in the past 3-4 years. Adjacent same-season planting greatly accelerates spread of an outbreak in either crop.

    Timing: Maintain 3-4 year rotation interval; physically separate beds within the same garden.

    Source: Penn State Extension, S7

  • StrawberryEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismdisease-host

    Shared Verticillium wilt susceptibility. Avoid planting strawberry after tomato in the same bed for at least 3 years.

    Source: S1, UC IPM

  • Ají PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Shares Solanaceae disease and pest complex with tomato. Group in rotation but do not interplant in adjacent rows.

    Source: S7

  • ButternutEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsallelopathy-negative

    Butternut produces juglone at lower concentrations than black walnut but still measurable; sensitive species (Solanaceae, blueberry, ericaceous shrubs) can be affected within the dripline.

    Source: S5, S16

  • Cape GooseberryEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Cape gooseberry shares the Solanaceae pest/disease complex with tomato, including three-lined potato beetle, Colorado potato beetle, and Verticillium wilt.

    Source: Penn State Extension

  • Cayenne PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Cayenne shares the full Solanaceae disease and pest complex with tomato and potato (Phytophthora, Verticillium, tobacco mosaic virus, Colorado potato beetle, hornworms). Treat cayenne the same as bell/hot pepper in spacing and rotation.

    Source: S7, University of Maryland Extension

  • Common EggplantEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Tomato and eggplant share early blight, Verticillium, and bacterial spot. Rotate as a Solanaceae group rather than alternating in adjacent rows.

    Source: S7, University of Maryland Extension

  • Common TomatoEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Currant tomato is closely related to S. lycopersicum and shares the full Solanaceae pest/disease complex. Same rotation and adjacency rules apply.

    Source: S7

  • CornEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsalternate-host-pest

    Corn earworm and tomato fruitworm are the same species (Helicoverpa zea); moths emerging from corn move readily to tomato fruit. Avoid contiguous plantings or stagger to break the cycle.

    Timing: Separate corn and tomato by at least 6-9 m or stagger plantings so silking corn and fruiting tomato do not overlap.

    Region: Pressure increases from north to south; severe in the South and Mid-Atlantic.

    Source: Penn State Extension, S11, UC IPM Pest Notes

  • Currant TomatoEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Currant tomato is closely related to S. lycopersicum and shares the full Solanaceae pest/disease complex. Same rotation and adjacency rules apply.

    Source: S7

  • English WalnutEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsallelopathy-negative

    English walnut produces juglone at lower concentrations than black walnut, but enough to affect highly sensitive species (Solanaceae, blueberry, ericaceous shrubs) within the dripline. Most commercial English walnut in CA is grafted on black walnut rootstock, which also exudes juglone from roots — so the AVOID list is functionally the same as for black walnut.

    Region: California Central Valley walnut orchards; effect more pronounced where black walnut rootstock is used.

    Source: UC IPM, S5

  • Ground CherryEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Ground cherry (Physalis pruinosa) is host to three-lined potato beetle and shares Verticillium and Phytophthora susceptibility with tomato.

    Source: Penn State Extension, S7

  • Habanero PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Shares the Solanaceae disease/pest complex with tomato. Rotate as a group, do not co-plant in adjacent rows.

    Source: S7

  • Hot PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Hot pepper shares Solanaceae disease and pest complex with tomato (bacterial spot, Phytophthora, hornworms, aphids). Group with tomato in rotation but do not alternate them in adjacent rows year-on-year.

    Source: S7, University of Maryland Extension

  • Japanese WalnutEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsallelopathy-negative

    All Juglans species produce juglone (5-hydroxy-1,4-naphthoquinone) to varying degrees. Japanese walnut and its butternut hybrid 'heartnut' produce juglone at levels intermediate between black walnut and English walnut — enough to affect sensitive species (Solanaceae, blueberry) within the dripline.

    Source: S5, S16

  • Jerusalem ArtichokeEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsallelopathy-negative, nutrient-competition

    Same rationale as for bean; sunchoke crowds and shades adjacent crops and is hard to eradicate once established.

    Source: S7

  • PeanutEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host

    Peanut and tomato share susceptibility to Sclerotium rolfsii (southern blight) and several Fusarium and Rhizoctonia species. Sequential or adjacent plantings can build up shared soilborne inoculum.

    Region: Warm humid regions (zones 7+).

    Source: S11

  • PeppermintEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsnutrient-competition

    Same competition warning as spearmint — never plant peppermint directly in the bed with annual vegetables.

    Source: University of Maryland Extension

  • Rocoto PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Companion interactions equivalent to other domesticated Capsicum spp.; rocoto shares the Solanaceae disease/pest complex with tomato. Note rocoto requires cooler summer nights than other peppers, so it is grown at small scale in coastal Pacific Northwest and high elevation only.

    Region: Limited US production: Pacific Northwest, high-elevation regions.

    Source: S4

  • SpearmintEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsnutrient-competition

    Mint's aggressive rhizomes outcompete tomato roots if planted directly in the bed. Use containers to keep volatile oils available without root invasion.

    Source: University of Maryland Extension

  • Sweet Bell PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Peppers and tomatoes are both in Solanaceae and share major diseases (Phytophthora capsici, Verticillium wilt, bacterial spot, several mosaic viruses) and pests (aphids, flea beetles). Extension rotation guidance advises grouping Solanaceae but rotating the entire group off the bed for 3-4 years rather than alternating tomato and pepper in adjacent rows.

    Source: S7, University of Maryland Extension

  • Sweet PotatoEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Sweet potato and tomato share several pests including whitefly, southern root-knot nematode (Meloidogyne incognita), and tomato spotted wilt virus reservoirs. NC State recommends rotating sweet potato away from Solanaceae cash crops in nematode-prone soils.

    Timing: Maintain ≥2-year rotation between sweet potato and Solanaceae.

    Region: Southeast, especially sandy nematode-prone soils.

    Source: S11, NC State Extension

  • Tabasco PepperEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Shares Solanaceae disease/pest complex with tomato.

    Source: S7

  • TomatilloEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsdisease-host, alternate-host-pest

    Tomatillo shares the full Solanaceae pest and disease complex with tomato (early blight, Phytophthora, hornworms, three-lined potato beetle which specifically targets tomatillo and Physalis). Rotate as a group, do not co-plant.

    Source: Penn State Extension, S7

  • BroccoliEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Shared brassica/tomato conflict; see common cabbage.

    Source: University of Maryland Extension

  • Brussels SproutsEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Shared brassica/tomato nutrient and pH conflict; see common cabbage.

    Source: University of Maryland Extension

  • Common CabbageEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition, allelopathy-negative

    Tomato and Brassica crops compete for the same shallow-zone N and Brassicas release glucosinolate-derived isothiocyanates that can stunt nearby Solanaceae. Most extension home-garden guides advise not interplanting tomatoes with cabbage/broccoli/kale, although controlled-trial evidence on the allelopathy mechanism in field conditions is limited.

    Source: S7, University of Maryland Extension

  • Common KaleEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Shared brassica/tomato nutrient and pH conflict; see common cabbage for full discussion.

    Source: University of Maryland Extension

  • Downy Ground CherryEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationdisease-host, alternate-host-pest

    As a Physalis species, shares the Solanaceae pest and disease complex with tomato; companion guidance equivalent to ground-cherry entry.

    Source: Penn State Extension

  • Florence FennelEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationallelopathy-negative

    Same fennel allelopathy as sweet fennel; isolate Florence fennel in its own bed.

    Source: University of Maryland Extension

  • KohlrabiEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Shared brassica/tomato conflict; see common cabbage.

    Source: University of Maryland Extension

  • OkraEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationalternate-host-pest, disease-host

    Okra and tomato share several pests (stink bugs, root-knot nematode) and Verticillium susceptibility; Southern extension generally suggests not following tomato with okra in nematode-prone soils.

    Region: Southeast.

    Source: S11

  • PecanEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationallelopathy-negative

    Pecan produces juglone in lower concentrations than black walnut, but sensitive Solanaceae (tomato, pepper, eggplant) can still show stunting near mature pecan trees. UGA and Texas A&M note this as a soft caution rather than a strict avoidance.

    Region: Southeast and Texas/Oklahoma pecan country.

    Source: S11

  • Romanesco Broccoli / CauliflowerEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Calcium competition is especially relevant for cauliflower (susceptible to tip-burn / brown bead) — pairing with another heavy calcium feeder is discouraged. See common cabbage.

    Source: University of Maryland Extension

  • RutabagaEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationnutrient-competition

    Shares the Brassicaceae / tomato avoidance flagged by extension references (calcium and nitrogen competition, soil-pH mismatch). See common cabbage for complete relationships.

    Source: University of Maryland Extension

  • Shagbark HickoryEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationallelopathy-negative

    Same as shellbark: hickories produce juglone (lower than walnut) and sensitive Solanaceae can be affected within the dripline.

    Source: S5

  • Shellbark HickoryEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationallelopathy-negative

    Hickories produce juglone in lower concentrations than walnut but enough to mildly affect sensitive species (tomato, pepper, eggplant, blueberry) within the dripline. Extension caution rather than firm avoidance.

    Source: S5

  • Sweet FennelEvidence tier C: Traditional practice with plausible mechanism but limited empirical replicationallelopathy-negative

    Fennel (Foeniculum vulgare) releases anethole-related allelochemicals reported to stunt tomato and most vegetable neighbors. Listed across multiple extension companion-planting summaries.

    Source: S7

Biofumigant cover crops (1)

  • Cover MustardEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsbiofumigation

    Mustard biofumigation ahead of tomato suppresses Verticillium and some root-knot nematode populations; documented in WSU and Cornell trials.

    Timing: Incorporate at full bloom; wait 2-3 weeks before transplant.

    Source: S1, S4

Good successors in rotation (7)

  • Cereal RyeEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismallelopathy-positive, weed-suppression, soil-conditioning

    Cereal rye residues release benzoxazinoids (DIBOA, BOA) and short-chain phenolic acids that suppress small-seeded weeds for 4-10 weeks after termination. Transplanted tomato (large transplant, deep root) tolerates the residue while weeds are suppressed. SARE and Northeast Cover Crop Council document this as a foundational no-till tomato system.

    Timing: Chemical allelopathy from rye benzoxazinoids declines in soil over ~2 weeks after termination (Rice et al., 2012 and Cornell-affiliated reviews); physical mulch suppression of weeds persists longer (4–10 weeks depending on residue mass). Direct-seeding of small-seeded crops should still wait ~3–4 weeks; transplanted tomato can typically go in 1–2 weeks after termination.

    Region: Effective across the Northeast, Mid-Atlantic, and Midwest; less reliable in the deep South where rye biomass is lower.

    Source: SARE, S29, Putnam, 1988

  • Crimson CloverEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismn-fixation, weed-suppression

    Fall-seeded crimson clover terminated in spring delivers 90-130 lb N/acre to the following tomato crop. Rodale's no-till tomato-into-rolled-crimson system is well documented and widely replicated.

    Timing: Roller-crimp at full bloom; transplant tomato 1-2 weeks later.

    Region: Reliable mid-Atlantic, Southeast, and Pacific Northwest.

    Source: Rodale Institute, SARE, S29

  • Hairy VetchEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismn-fixation, weed-suppression, disease-host

    Hairy vetch is the foundational legume of no-till tomato systems: fixes 80-180 lb N/acre and the rolled mulch reduces foliar disease (Septoria, early blight) by ~20-40% via splash-block effect. USDA-ARS Beltsville (Abdul-Baki & Teasdale) documented yield improvements vs. bare-ground and black-plastic systems.

    Timing: Roller-crimp at full bloom (mid-May mid-Atlantic); transplant tomato into rolled mulch within 1 week.

    Region: Mid-Atlantic and Southeast best documented; zones 5-8.

    Source: SARE, USDA ARS, S29

  • RyeEvidence tier A: Peer-reviewed studies in US/Canada production conditions with a clear mechanismweed-suppression, allelopathy-positive

    Roll-crimped or mowed rye produces a thick mulch that suppresses weeds in transplanted tomato. Rodale's no-till tomato system is built on this practice; mid-Atlantic extension trials confirm.

    Timing: Roll at anthesis (full pollen shed) for clean kill; transplant tomato through residue 1-2 weeks later.

    Region: Mid-Atlantic, Northeast.

    Source: Penn State Extension, Rodale Institute

  • Fava BeanEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsn-fixation, soil-conditioning

    Overwintered fava terminated in spring is a documented predecessor for heavy-feeding summer crops including tomato. Residual N and improved soil tilth benefit the following Solanaceae crop.

    Timing: Terminate fava 2-3 weeks before tomato transplant to allow residue partial decomposition.

    Region: Mild-winter regions where fall sowing is possible (PNW, coastal CA, mid-Atlantic).

    Source: S4, Rodale Institute

  • SorghumEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsweed-suppression, biofumigation, soil-conditioning

    Sorghum-sudangrass summer cover ahead of fall-transplanted tomato or following spring tomato provides biomass, weed suppression, and root-knot nematode suppression in some trials. Transplanting (vs. seeding) avoids the allelopathic stand reduction.

    Region: Mid-Atlantic, Southeast.

    Source: Penn State Extension, S29

  • Sorghum-SudangrassEvidence tier B: Extension consensus across multiple US/Canada land-grant institutionsallelopathy-positive, weed-suppression, soil-conditioning

    Sorghum-sudangrass roots exude sorgoleone, a potent allelochemical that suppresses small-seeded weeds and is implicated in nematode suppression (root-knot Meloidogyne spp., root-lesion Pratylenchus spp.). High biomass (5-8 tons/acre) builds soil organic matter. SARE and Cornell Soil Health document widely.

    Timing: Mow when 3-4 ft tall to encourage rooting; terminate at frost; allow 3-4 weeks before transplanting following crop.

    Region: Warm-season; requires soils >65°F at planting. Most useful in summer fallow windows in vegetable rotations.

    Source: SARE, S29, Putnam, 1988

Sources cited

S1
Cornell University Cooperative Extension — vegetable production guides
S10
University of Wisconsin–Madison Extension
S11
University of Georgia Cooperative Extension
S12
NC State Extension
S13
University of New Hampshire Extension
S16
Cornell Climate Smart Farming / Cornell Small Farms
S17
Rodale Institute
S18
SARE (Sustainable Agriculture Research and Education)
S20
USDA ARS (Agricultural Research Service) publications
S27
Eliot Coleman — *The New Organic Grower*
S28
Bekele & Hassanali, 2001 — basil volatile bioassay
S29
Cornell Soil Health Lab / Northeast Cover Crop Council (NECCC)
S3
UC IPM (University of California Agriculture and Natural Resources)
S33
Putnam, 1988 — cereal rye allelopathy review
S34
UC IPM Pest Notes — specific pest pages
S4
Oregon State University Extension Service
S5
Michigan State University Extension
S6
Penn State Extension
S7
University of Minnesota Extension
S8
Iowa State University Extension and Outreach
S9
University of Maryland Extension — Home & Garden Info Center

Care & troubleshooting— extension-sourced, with citations

When to feed, prune & water

Attract beneficial insects and protect pollinators

Protection
  • Routine carePlant insectary flowers and tolerate light pestsstrong evidence — extension confidence

    Grow a diversity of flowering plants (including small-flowered umbels and asters) to feed predators and parasitoids, and tolerate low pest numbers so natural enemies have prey to stick around.

    Source: UC IPM; UMN Extension

  • Routine careNever spray open bloomsstrong evidence — extension confidence

    Avoid insecticides on flowering plants and apply any needed sprays in the evening when pollinators aren't active, and favor selective products over broad-spectrum ones to spare bees and beneficials.

    Source: UC IPM

Mulch to suppress weeds and retain moisture

Mulch
  • Routine careApply organic mulch around plantsstrong evidence — extension confidence

    Spread a few inches of straw, shredded leaves, or compost around established plants (keeping it off stems) to hold soil moisture, suppress weeds, and moderate soil temperature; wait until soil has warmed for heat-loving crops.

    Source: UMN Extension; Missouri Botanical Garden

Plan crop rotation

Rotation
  • Routine careRotate plant families between bedsstrong evidence — extension confidence

    Avoid planting the same family in the same bed in consecutive years (aim for a 3+ year gap), grouping crops by family so soilborne diseases and pests that build up don't carry over to the next susceptible crop.

    Source: UMN Extension; Cornell

  • Routine careSequence for soil healthmoderate evidence — extension confidence

    Follow heavy feeders like tomatoes and brassicas with legumes or a cover crop to support soil fertility and structure, and keep simple notes each year so you can track where each family grew.

    Source: UMN Extension

Protect the garden from deer

Protection
  • Routine careFence the gardenstrong evidence — extension confidence

    A fence about 8 feet tall and tight to the ground is the most reliable barrier; an outward-angled or double fence, or monofilament line strung at 30 to 36 inches, can also deter deer on smaller beds.

    Source: UMN Extension; Cornell CCE

  • Routine careRotate repellents as a supplement· every 2 wksmoderate evidence — extension confidence

    Where fencing isn't feasible, apply odor/taste repellents and alternate formulations, reapplying every couple of weeks and after rain; combining repellents with fencing works best.

    Source: UMN Extension; PennState Extension

Water deeply at fruiting

Watering
  • Routine careProvide steady deep watering during fruiting· every 3 daysstrong evidence — extension confidence

    Once plants begin flowering and setting fruit, supply about 1 to 1.5 inches of water per week in deep soakings rather than light sprinkles, ideally at the base; even moisture reduces cracking, blossom-end rot, and bitter or misshapen fruit.

    Source: UMN Extension: Tomato disorders; UMN Extension: Growing tomatoes

Clean up debris and sanitize at season end

Sanitation

Unusual this time of year.

  • Routine careRemove spent plants and fallen debrisstrong evidence — extension confidence

    Pull and clear old plants, dropped fruit, and leaf litter at season end, since many pests and diseases overwinter in this debris; dispose of diseased material rather than composting it.

    Source: UMN Extension; Cornell

  • Routine careClean tools, stakes, and cagesmoderate evidence — extension confidence

    Wash and sanitize stakes, cages, and tools that touched diseased plants before storing or reusing them to avoid carrying pathogens into next season.

    Source: Cornell; UMN Extension

Cutworm collars at transplant

Protection

Unusual this time of year.

  • Routine careSet a collar around each new transplantstrong evidence — extension confidence

    When setting out transplants, slip a collar (a toilet-paper tube, paper cup with the bottom cut out, or similar) around each stem and press it a couple inches into the soil so it stands a few inches above ground, blocking cutworms from the stem.

    Source: UMN Extension: Cutworms; UC IPM: Cutworms

Harden off seedlings

Protection

Unusual this time of year.

Read: starting seeds indoors

Something looks wrong?

Describe what you see on your ground cherryand we'll rank the likely causes — most likely first, least-invasive fix first.

Bacterial soft rot

Diseasesevere

Symptoms: mushy water-soaked decay of fleshy tissue; slimy soft rot of heads, bulbs, roots, or fruit; foul odor from rotting tissue; rapid collapse after wounding or in warm wet conditions; rot spreading in storage

  • CulturalRemove rotting plants and produce (manage, not cure)strong evidence — extension confidence

    Soft rot can't be cured once tissue breaks down; promptly remove and discard affected plants and produce so the bacteria don't spread to neighbors or other stored vegetables.

    Source: Cornell NYS IPM

  • CulturalAvoid wounds and excess moisturestrong evidence — extension confidence

    Harvest in dry conditions, handle gently to avoid bruising, control insects that create entry wounds, and improve drainage; cure and store bulbs and roots cool and dry.

    Source: Cornell NYS IPM

  • CulturalDon't overwater and rotatemoderate evidence — extension confidence

    Avoid waterlogged soil and overhead watering that splashes bacteria, and rotate away from previously affected fleshy crops to lower disease pressure.

    Source: Cornell NYS IPM

Fusarium / Verticillium wilt

Diseasesevere

Symptoms: wilting that doesn't recover overnight; yellowing climbs one side or one branch first; brown streaking inside a cut stem

  • CulturalRemove the plant; rotate and choose resistant varietiesstrong evidence — extension confidence

    There is no cure once a plant is infected. Pull it, avoid planting the same family there for 3-4 years, and grow V/F-resistance-coded varieties next season.

    Source: UMN Extension: Tomato Wilts

Read: diagnosing leaf spots & yellowing

Late blight

Diseasesevere

Symptoms: large greasy gray-green blotches on leaves; white fuzzy growth on undersides in damp weather; brown firm rot on fruit/tubers; spreads fast in cool wet spells

  • CulturalRemove and bag infected plantsstrong evidence — extension confidence

    Late blight is highly contagious and can wipe out a planting in days. Pull and bag (don't compost) symptomatic plants to protect neighbors and nearby gardens.

    Source: Cornell: Late Blight

Phytophthora blight (root and crown rot)

Diseasesevere

Symptoms: sudden wilting and collapse of peppers or squash; dark water-soaked lesions at the crown or stem base; white cottony growth on infected fruit; root and crown rot; vine and fruit rot after heavy rain or in wet low spots

  • CulturalRemove affected plants at first sign (manage, not cure)strong evidence — extension confidence

    Infected plants can't be saved; promptly pull and destroy them at the start of an outbreak to slow spread, and avoid working in beds when wet.

    Source: Cornell Vegetables; UMN Extension

  • CulturalImprove drainage and avoid waterloggingstrong evidence — extension confidence

    Plant on raised beds, never let beds stay saturated, and water with drip rather than flooding, since this water mold thrives in standing water and saturated soil.

    Source: Cornell Vegetables; UMN Extension

  • CulturalRotate and choose tolerant varietiesmoderate evidence — extension confidence

    Rotate out of peppers, cucurbits, and tomatoes for at least three years where the disease has occurred, and select tolerant or resistant varieties when available.

    Source: Cornell Vegetables

Root-knot nematodes

Nematodesevere

Symptoms: galls or knots along roots; stunted plants; yellowing and midday wilting that recovers at night; poor vigor despite good care; patchy poor growth in beds

  • CulturalConfirm with a soil test, then rotate (manage, not cure)strong evidence — extension confidence

    Root-knot nematodes can't be eradicated from garden soil, so confirm via a county Extension nematode assay and rotate beds to non-hosts or resistant varieties (look for VFN-type resistance in tomato).

    Source: Clemson HGIC; UF/IFAS

  • CulturalPlant suppressive cover/rotation cropsmoderate evidence — extension confidence

    A solid planting of French marigolds grown 2+ months and turned under, or cover crops such as sorghum-sudangrass or cowpea, can lower populations between susceptible crops.

    Source: UF/IFAS; Clemson HGIC

  • CulturalSanitation and organic mattermoderate evidence — extension confidence

    Avoid moving infested soil on tools or transplants, build soil organic matter to support beneficial organisms, and keep plants well watered to help them tolerate root damage.

    Source: UC IPM; Clemson HGIC

Southern blight

Diseasesevere

Symptoms: sudden wilting in hot weather; yellowing then collapse of whole plant; white fan-like mold mat at the stem base and soil; tan-brown mustard-seed-sized sclerotia near soil line; girdled rotted lower stem

  • CulturalRemove infected plants and surrounding soil (manage, not cure)strong evidence — extension confidence

    Once a plant collapses it can't be cured; dig out the plant plus the top few inches of nearby soil containing sclerotia and dispose of it, avoiding spread on tools.

    Source: Clemson Land-Grant Press; UC IPM

  • CulturalBury residue and rotatemoderate evidence — extension confidence

    Deep-turn soil to bury sclerotia, remove crop debris at season end, and rotate susceptible solanaceous and legume crops with grasses for several seasons.

    Source: Clemson Land-Grant Press

  • CulturalAdjust soil pH and plant earlymoderate evidence — extension confidence

    Maintain soil pH at the level recommended for the crop, since the disease is worse in low-pH soils, and time plantings so harvest begins before peak summer heat favors the fungus.

    Source: Clemson Land-Grant Press

Tomato spotted wilt virus

Virussevere

Symptoms: bronzing or purpling of young leaves; ringspots and concentric rings on leaves and fruit; one-sided or stunted growth; dark streaks on stems; mottled or blotchy ripening fruit

  • CulturalRemove infected plants (cannot be cured)strong evidence — extension confidence

    There is no cure once a plant is infected, so promptly pull and dispose of symptomatic plants to reduce the virus reservoir that thrips spread to healthy plants.

    Source: UC IPM; UMN Extension

  • CulturalStart clean and control weeds and thripsstrong evidence — extension confidence

    Use virus- and thrips-free transplants, choose resistant varieties (Sw-5 tomatoes, Tsw peppers) where available, and control weeds around the garden that harbor both virus and thrips vectors.

    Source: UC IPM; UF/IFAS

Read: diagnosing leaf spots & yellowing

White mold (Sclerotinia stem rot)

Diseasesevere

Symptoms: water-soaked stem or branch lesions; fluffy white cottony mold on stems and pods; sudden wilting of part of a plant; hard black sclerotia inside or on stems; collapse during cool wet bloom periods

  • CulturalRemove infected plants (manage, not cure)strong evidence — extension confidence

    There's no cure for an infected plant; cut out and bag affected plants including the black sclerotia, and don't compost them, since sclerotia survive years in soil.

    Source: UMN Extension; UC IPM

  • CulturalOpen the canopy and rotatestrong evidence — extension confidence

    Space plants widely, control weeds, orient rows to prevailing wind, and avoid overhead watering at bloom to dry the canopy; rotate to non-host crops (corn or other grasses) for several years.

    Source: UMN Extension; UC IPM

  • CulturalWater at the base, not overheadmoderate evidence — extension confidence

    Use drip or soaker irrigation to keep foliage and the soil surface drier, which discourages the sclerotia germination and mycelial growth that drive white mold.

    Source: UC IPM

Blister beetles

Pestmoderate

Symptoms: swarms of elongated soft-bodied beetles; rapid defoliation of leaves and flowers; gray, black, or striped beetles clustered on plants; skeletonized foliage on tomatoes and beans

  • CulturalHand-pick wearing gloves· every 2 daysmoderate evidence — extension confidence

    Wear gloves (these beetles release a blistering fluid) and knock beetles into soapy water, or use row cover ahead of swarms; their larvae eat grasshopper eggs, so tolerate light feeding when you can.

    Source: UMN Extension; Missouri Botanical Garden

  • OrganicSpot-treat heavy swarms· every 1 wkmoderate evidence — extension confidence

    If a large swarm threatens a planting, a pyrethrin or other labeled insecticide can knock them back per the label; avoid spraying open blooms to protect pollinators.

    Always follow the product label — it is the law.

    Source: Missouri Botanical Garden

Botrytis gray mold

Diseasemoderate

Symptoms: fuzzy gray-brown mold on leaves, stems, flowers, or fruit; soft watery rot on fruit and blossoms; dieback from cut or wounded stems; mold spreading in cool humid still conditions; blighted flowers that fail to set

  • CulturalRemove infected tissue and old blossomsstrong evidence — extension confidence

    Prune out moldy leaves, stems, and fruit and clear fallen blossoms and debris where the fungus gets started, disposing of them rather than composting.

    Source: UMN Extension; Cornell

  • CulturalImprove airflow and reduce leaf wetnessstrong evidence — extension confidence

    Space and stake plants for good air movement, water at the base in the morning, and harvest ripe fruit promptly so botrytis has fewer cool, humid, wet surfaces to colonize.

    Source: UMN Extension; Cornell

Damping-off (seedlings)

Diseasemoderate

Symptoms: seedlings flop over and collapse at the soil line; thin water-soaked pinched stem base; fungus gnats or constantly wet mix

  • CulturalDry out, ventilate, sow into clean mixstrong evidence — extension confidence

    Use sterile seed-starting mix, bottom-water and let the surface dry between waterings, add airflow, and don't over-sow. Damping-off can't be cured once a seedling collapses.

    Source: UMN Extension: Damping-off

Read: starting seeds indoors

Early blight

Diseasemoderate

Symptoms: yellow leaves with dark concentric-ring (bullseye) spots; spotting marches up from the bottom; oldest/lowest leaves first

  • CulturalRemove affected lower leavesstrong evidence — extension confidence

    Pick off spotted leaves into the trash (not compost). Mulch heavily to stop soil splash and water at the base.

    Source: UMass Extension

  • CulturalPrune for airflowstrong evidence — extension confidence

    Thin crowded interior foliage so leaves dry quickly after rain or dew.

    Source: UMass Extension

  • ChemicalCopper - label use only· every 1 wk · ~4 wksmoderate evidence — extension confidence

    Only if established and spreading. Apply per label every 7-10 days; follow rates and pre-harvest intervals.

    Always follow the product label — it is the law.

    Source: Cornell Vegetable MD Online

Read: diagnosing leaf spots & yellowing

Herbicide drift damage (growth-regulator)

Disordermoderate

Symptoms: cupped, curled, or strap-like distorted new leaves; twisted stems and petioles; parallel veins on narrowed young leaves; stunting and delayed fruiting; symptoms appearing on new growth days after a nearby spray

  • CulturalIdentify the source and protect future plantingsstrong evidence — extension confidence

    Growth-regulator herbicides like 2,4-D and dicamba cause this distortion via drift or contaminated sprayers and mulch; identify and stop the source, and never use a sprayer that previously held herbicide on the garden.

    Source: UMN Extension; PennState Extension

  • CulturalSupport recovery if exposure was lightmoderate evidence — extension confidence

    Plants only lightly exposed (not directly sprayed) often outgrow the damage; keep them watered and lightly fed so they can push out normal new growth, though fruiting may be delayed.

    Source: UMN Extension

Japanese beetles

Pestmoderate

Symptoms: leaves skeletonized between veins; lacy chewed foliage; metallic green-bronze beetles clustered on plants; feeding worst in warm midsummer sun

Potassium deficiency

Deficiencymoderate

Symptoms: yellowing and browning along older leaf margins; scorched curled leaf edges; weak stems; poor or uneven fruit ripening; symptoms starting on lower, older leaves

  • CulturalConfirm with a soil test firststrong evidence — extension confidence

    Edge scorch on older leaves has several causes, so get a soil test before adding potassium; over-applying can lock out magnesium and calcium.

    Source: UMN Extension; Missouri Botanical Garden

  • OrganicApply potassium per soil-test guidancemoderate evidence — extension confidence

    If the test confirms low potassium, apply a potassium source (such as sulfate of potash) at the labeled/test-recommended rate and keep watering even, since drought worsens uptake.

    Always follow the product label — it is the law.

    Source: UMN Extension

Read: diagnosing leaf spots & yellowing

Root rot from overwatering / poor drainage

Diseasemoderate

Symptoms: stunted yellowing plants that wilt despite wet soil; soft brown mushy roots; sloughing root outer layer leaving thread-like core; poor growth in low or compacted wet spots; seedlings collapsing at the soil line

Spider mites

Pestmoderate

Symptoms: fine pale stippling/speckling on leaves; fine webbing on undersides in hot dry spells; leaves bronzing and dropping

  • CulturalHose down and raise humidity· every 3 days · ~2 wksstrong evidence — extension confidence

    Mites thrive in hot, dry, dusty conditions. Spray foliage (especially undersides) with water to dislodge them and reduce dust.

    Source: UC IPM

  • OrganicInsecticidal soap or horticultural oil - label use only· every 5 days · ~2 wksmoderate evidence — extension confidence

    Apply to undersides per label; mites resist many products, so soaps/oils are preferred. Not in extreme heat.

    Always follow the product label — it is the law.

    Source: UC IPM

Stink bugs (brown marmorated and native)

Pestmoderate

Symptoms: cloudy or corky spots on fruit; dimpled or pitted fruit; catfacing on tomatoes; shield-shaped brown or green bugs; barrel-shaped egg clusters on leaf undersides

  • CulturalExclude with row cover and clear nearby weedsstrong evidence — extension confidence

    Cover susceptible crops with floating row cover before bugs arrive, and remove weeds and groundcover near the garden in early spring where stink bugs feed before moving to crops. Lift covers on flowering crops that need pollination.

    Source: UMN Extension; UC IPM Pest Notes

  • CulturalHand-pick bugs and egg masses· every 3 daysstrong evidence — extension confidence

    Scout in the morning and drop adults, nymphs, and egg clusters into a bucket of soapy water; regular hand-picking keeps low populations in check since most garden insecticides work poorly on adults.

    Source: UMN Extension; UC IPM

  • OrganicSpot-treat young nymphs if numbers climb· every 1 wkmoderate evidence — extension confidence

    If small nymphs are abundant, a botanical such as pyrethrin or azadirachtin, or insecticidal oil, may give some suppression per the label; adults are largely unaffected, so rely mainly on exclusion and hand-picking.

    Always follow the product label — it is the law.

    Source: UC IPM

Thrips on fruiting vegetables

Pestmoderate

Symptoms: silvery or stippled flecking on leaves; black specks of frass; distorted or scarred young leaves and fruit; tiny slender insects in flowers; deformed fruit set

  • CulturalRemove weed and crop reservoirsstrong evidence — extension confidence

    Control flowering weeds in and around the garden and remove spent host crops promptly, since thrips build up on these and move onto fruiting vegetables; avoid planting next to onions, garlic, or cereals where thrips numbers spike.

    Source: UC IPM; UF/IFAS

  • CulturalKeep plants vigorous and rinse foliagemoderate evidence — extension confidence

    Water and feed adequately so plants tolerate feeding, and a forceful water spray can knock down populations; reflective mulch can also deter thrips from settling on young plants.

    Source: UC IPM

  • OrganicTreat with spinosad or oil if needed· every 1 wkmoderate evidence — extension confidence

    If thrips are damaging growing points or fruit, spinosad or insecticidal soap/oil can help per the label; rotate modes of action and avoid spraying open blooms to protect pollinators and natural enemies.

    Always follow the product label — it is the law.

    Source: UC IPM; UF/IFAS

Tomato hornworm

Pestmoderate

Symptoms: large green caterpillars with a tail horn; whole leaves and stem tips stripped overnight; dark frass pellets

  • CulturalHand-pick (leave parasitized ones)· every 2 days · ~3 wksstrong evidence — extension confidence

    Pick hornworms by hand at dusk. If one is covered in white rice-like cocoons, leave it - those are beneficial parasitic wasps doing your work.

    Source: UMN Extension

  • OrganicBt - label use only· every 1 wk · ~2 wksmoderate evidence — extension confidence

    For heavy infestations, Bt kurstaki per label targets the caterpillars.

    Always follow the product label — it is the law.

    Source: UMN Extension

Whiteflies

Pestmoderate

Symptoms: clouds of tiny white insects fly up when plants are disturbed; yellowing stippled leaves; sticky honeydew and black sooty mold; weak stunted growth

  • CulturalRemove infested leaves and hose off· every 4 daysmoderate evidence — extension confidence

    Pick off and discard heavily infested lower leaves and rinse colonies off undersides with a strong spray of water; yellow sticky cards help monitor numbers.

    Source: UC IPM: Whiteflies

  • OrganicApply a labeled soap or oil· every 1 wk · ~3 wksmoderate evidence — extension confidence

    Apply a labeled insecticidal soap or neem oil per the label, covering leaf undersides; these reduce but won't eliminate whiteflies, so repeat as needed.

    Always follow the product label — it is the law.

    Source: UC IPM: Whiteflies

Cutworms

Pestmoderate

Unusual this time of year.

Symptoms: seedlings cut off at soil line; transplants toppled overnight; wilted clipped plants in a row; chewed stems near ground; gray-brown caterpillars curled in soil

  • CulturalPlace stem collars on transplantsstrong evidence — extension confidence

    Push a collar (cardboard tube, can, or cup with bottom removed) a couple inches into the soil around each stem so it extends a few inches above ground; this blocks cutworms from reaching the stem.

    Source: UMN Extension: Cutworms; UC IPM: Cutworms

  • CulturalScout soil and hand-remove· every 3 days · ~2 wksstrong evidence — extension confidence

    In the evening or early morning, check the soil around damaged plants and remove curled larvae by hand; tilling beds about two weeks before planting also reduces larvae and pupae.

    Source: UMN Extension: Cutworms; UC IPM: Cutworms

  • OrganicApply a labeled Bt or spinosad· every 1 wk · ~3 wksmoderate evidence — extension confidence

    If damage continues, apply a labeled Bacillus thuringiensis (kurstaki) or spinosad product per the label, targeting small larvae; Bt works best on young first- and second-instar cutworms.

    Always follow the product label — it is the law.

    Source: UC IPM: Cutworms

Phosphorus deficiency

Deficiencymoderate

Unusual this time of year.

Symptoms: stunted plants with dark dull green leaves; reddish or purplish tint on leaves and undersides; delayed maturity and poor fruiting; symptoms worst in cold spring soils; older leaves affected first

  • CulturalCheck soil test and soil temperaturestrong evidence — extension confidence

    Purpling in cold spring soils is often temporary, since cold roots can't take up phosphorus that's actually present; warm weather usually resolves it, so confirm a true shortage with a soil test before adding phosphorus.

    Source: UMN Extension; Missouri Botanical Garden

  • OrganicAdd phosphorus only if the test calls for itmoderate evidence — extension confidence

    If low phosphorus is confirmed, work a phosphorus source into the root zone per the test recommendation, and keep soil pH in range since extreme pH ties up phosphorus.

    Always follow the product label — it is the law.

    Source: UMN Extension

Aphids

Pestlow

Symptoms: clusters of tiny soft-bodied insects on new growth and undersides; sticky honeydew or sooty mold; curled distorted new leaves; ants tending them

  • CulturalBlast off with water· every 3 days · ~2 wksstrong evidence — extension confidence

    Knock colonies off with a strong jet of water in the morning; repeat every few days. Light infestations rarely need more.

    Source: UC IPM: Aphids

  • OrganicInsecticidal soap - label use only· every 1 wk · ~3 wksmoderate evidence — extension confidence

    For persistent colonies apply insecticidal soap to undersides per label. Avoid open flowers.

    Always follow the product label — it is the law.

    Source: UC IPM

Edema (oedema)

Disorderlow

Symptoms: small watery blisters or bumps on leaf undersides; corky tan or brown scabby spots on leaves and stems; yellow flecking on upper leaf surface; worse in cool cloudy humid spells; not spreading plant to plant

Magnesium deficiency

Deficiencylow

Symptoms: yellowing between the veins of older leaves; veins stay green (interveinal); common in sandy soils and containers

  • CulturalConfirm with a soil test, then correct· every 2 wks · ~4 wksmoderate evidence — extension confidence

    Interveinal yellowing on older leaves suggests magnesium. Confirm with a test; if low, a dilute Epsom-salt foliar spray is a short-term fix while you amend the soil.

    Source: UMN Extension

Read: diagnosing leaf spots & yellowing

Nitrogen deficiency

Deficiencylow

Symptoms: oldest leaves uniformly pale yellow; plant pale and slow overall; common in containers and after heavy rain

  • CulturalFeed with balanced fertilizer· every 2 wks · ~4 wksstrong evidence — extension confidence

    Apply a balanced organic fertilizer or fish emulsion; new growth greens up within ~2 weeks. Don't overcorrect.

    Source: UMass Extension

Read: diagnosing leaf spots & yellowing

Sunscald

Disorderlow

Symptoms: pale leathery patch on the sun-exposed shoulder of fruit; follows heavy pruning or leaf loss

  • CulturalKeep canopy coverstrong evidence — extension confidence

    Stop over-pruning and let foliage shade the fruit; shade cloth helps in heat waves. Damaged fruit is still edible if you cut out the patch.

    Source: UMN Extension

Transplant shock

Disorderlow

Unusual this time of year.

Symptoms: wilting or drooping right after transplanting; stalled growth for days after setting out; leaf scorch or edge browning on new transplants; temporary yellowing; recovery once roots establish

  • CulturalWater in well and provide shade· every 1 days · ~1 wksstrong evidence — extension confidence

    Water transplants in thoroughly at planting and keep the root zone evenly moist for the first week or two, and provide temporary shade during hot, sunny, or windy spells to reduce stress while roots establish.

    Source: UMN Extension; Missouri Botanical Garden

  • CulturalHarden off and plant gently next timestrong evidence — extension confidence

    Most plants recover on their own; to prevent recurrence, harden off seedlings before planting, set them out in mild weather or evening, and avoid disturbing the roots when transplanting.

    Source: UMN Extension