First Frost Prep Guide: What to Do Before Temperatures Drop

The first frost of fall can feel like the official end of the gardening season, but it doesn’t have to be. While frost will finish off some warm-season favorites, many vegetables can tolerate chilly weather, and some actually improve after a light frost.

The key is knowing what needs to be harvested, what can stay put, and what’s worth protecting. A little preparation before that first frosty night can help you get more from your fall garden and make the transition into winter much easier.

First, know your frost date

Before you start pulling plants or covering garden beds, find your area’s average first frost date.

Your first frost date is an estimate based on historical weather data, not a guarantee. Frost can arrive earlier or later from year to year, so once you’re within a couple of weeks of that date, start paying closer attention to your local forecast.

A frost advisory generally means temperatures may fall low enough for frost to form, while a freeze occurs when temperatures reach 32°F or below. How long those temperatures last matters, too.

Harvest your frost-sensitive crops

Warm-season vegetables are generally the first plants you’ll need to worry about. Tomatoes, peppers, eggplants, cucumbers, squash, beans, melons, and basil can all be damaged by frost.

If frost is in the forecast, harvest any ripe produce you don’t want to lose. It’s also a good time to pick nearly mature fruits and vegetables that can continue ripening indoors.

Pay special attention to basil. It’s particularly sensitive to cold and can show damage even before temperatures reach freezing.

Don’t rush to harvest everything

Not every vegetable needs rescuing at the first mention of frost.

Many of our favorite fall crops are surprisingly cold tolerant. Kale, cabbage, broccoli, Brussels sprouts, carrots, radishes, spinach, lettuce, peas, and other cool-season vegetables can often withstand a light frost.

In fact, chilly temperatures can make certain vegetables taste even better. Crops like kale and carrots may become sweeter after exposure to cold as the plants convert some of their stored starches into sugars.

So before clearing your garden beds, check the cold tolerance of what you’re growing. There may be plenty of gardening season left!

Protect plants you want to keep growing

If you have tender plants that are still producing, a little protection can help you squeeze more time out of the season.

Cover plants before sunset so you can trap some of the warmth stored in the soil during the day. Frost cloth, row cover, sheets, or lightweight blankets can all provide protection. Avoid laying heavy material directly on delicate plants; use stakes or hoops for support when needed.

Make sure your covering extends all the way to the ground. You’re trying to hold warmer air around the plant, not simply protect its leaves.

Remove coverings the following morning once temperatures rise, particularly on sunny days.

Don’t forget your containers

Plants growing in containers need a little extra attention. Because their roots have less soil around them for insulation, containers can cool down more quickly than garden beds.

Move tender container plants into a garage, shed, porch, or other protected area overnight when possible. Even moving pots against the house can provide a little additional protection.

If a container is too large to move, cover the plant and consider insulating the pot itself.

Give the garden a drink

It may seem counterintuitive, but adequately watered soil can help protect plants during a cold night. Moist soil holds heat better than very dry soil.

If your garden is dry and frost is expected, water the soil earlier in the day. Avoid soaking the foliage right before temperatures drop—you’re looking to moisten the root zone.

Know the difference between frost damage and a dead plant

You walk outside the morning after a frost and find wilted or discolored leaves. Don’t immediately pull the plant.

Frost damage often appears as darkened, limp, or water-soaked foliage. Give the plant a little time before deciding what survived. Hardy plants may have damaged outer leaves while the growing point remains perfectly healthy.

Once you can clearly see the extent of the damage, remove dead material as needed.

Use the first frost as a cue to clean up

As warm-season crops finish, start clearing away spent plants, especially any that showed signs of disease. Healthy plant material can often go into the compost pile, while diseased material is usually best removed from the garden.

Pull weeds before they have another opportunity to set seed, clean up fallen fruit and debris, and make notes about what worked—and what didn’t—this season.

But don't feel like the entire garden needs to be spotless. Leaving some healthy plant material and stems can provide valuable winter habitat for beneficial insects and wildlife.

And keep planting!

First frost doesn’t necessarily mean planting season is over.

Depending on your growing zone, you may still have time for quick-growing greens and other cold-tolerant crops. In milder climates, fall and winter can be some of the best times to grow lettuce, spinach, kale, radishes, carrots, and other cool-season favorites.

Gardeners in colder regions can also use cold frames, row covers, low tunnels, and other season-extension techniques to keep harvesting well beyond the first frost.

A little prep goes a long way

The first frost is less of a finish line and more of a change in seasons. Harvest what can’t handle the cold, protect what needs a little help, and let your hardy fall crops enjoy the cooler weather.

And once everything is tucked in for the night, you can start thinking about what comes next—because there’s always another growing season to plan for.