Extend the Growing Season: Row Covers, Cold Frames & Frost Protection

GardenDraft Team · June 6, 2026 · 6 min read

Part of: Planting Calendar & Frost Date Guides

The frost dates that bracket your season are softer than they look, and a few simple tools — row covers, cold frames, cloches — let you extend the growing season past them at both ends. A little protection at each end buys you weeks: starting earlier in spring and, more rewarding, harvesting well past the first fall frosts while everyone else's gardens have gone to bed. None of it is complicated; it's mostly about trapping warmth and blocking cold.

How a few degrees of frost protection buys you weeks

Most season extension works by holding a thin layer of warmer air around the plants overnight, when cold does its damage. Raising the temperature just a few degrees can mean the difference between a killed crop and one that sails through, and because fall cools gradually, those few degrees often add two to four weeks of harvest. The same gear protects tender plants from a surprise late or early frost.

The toolkit, lightest to heaviest

Reach for the level of protection the forecast calls for:

• Floating row cover: lightweight fabric draped over hoops or laid right on the plants; adds a few degrees, lets in light and rain, and doubles as a pest barrier.
• Cold frames: a low box with a clear lid, like a mini-greenhouse, ideal for hardening off and overwintering greens.
• Cloches & tunnels: jars, bottles, or plastic-covered hoops that warm individual plants or a whole row.
• Quick frost cover: an old sheet or blanket thrown over plants for a single cold night, removed by morning.

Don't cook what you're trying to save

Covers that trap heat overnight can overheat plants on a sunny day, so vent or remove them when temperatures climb, especially with anything plastic or a closed cold frame. Anchor the edges well, since protection only works if cold air can't sneak underneath, and a cover that blows off at 2 a.m. does nothing. For a hard freeze, add a layer rather than relying on one thin sheet.

Stretch the fall garden further

Season extension is what makes a serious fall garden pay off — it protects the cool-season crops you sowed for autumn against the first frosts. Pair it with the timing in first frost date and fall garden planning and the crop choices in what to plant in July and August for a fall garden, and keep an eye on your local dates through the planting calendar.