How to Protect Plants From Frost: 7 Tips for Gardeners

In gardening, frost dates refer to the dates when the last spring frost and first fall frost occur. Gardeners use frost dates to determine when it will be safe to sow new seeds or transplant plants with less risk of them freezing. The gardening season begins each spring as frosty nights ease up and plants send out tender new shoots. Spring and summer bring an eruption of growth, flowering, and fruiting. With the arrival of fall and winter, plant growth slows to a stop as nights get cold and frost forms on the ground.

Plant and harvest these frost-hardy vegetables, which can survive colder temperatures, at the right time and you can enjoy homegrown produce and veggies year-round:

1. 1. Arugula: Plant arugula in late summer and prepare for it to ripen in your fall garden. Arugula greens are not a warm-season crop, so don't plant them too early or you'll get a bitter harvest.
2. 2. Brussels sprouts: A reliable cool-season crop, Brussels sprouts won’t suffer from one or two frosts. In fact, a little frost will make them sweeter, as plants produce sugars to cope with cold temperatures. But you should generally grow Brussels sprouts at temperatures between forty-five degrees and seventy-five degrees Fahrenheit.
3. 3. Bunching onions: These perennials grow year-round. If you plant them in late summer, you can get your first harvest in the fall, with more to follow in early spring.
4. 4. Cauliflower: A finicky plant, cauliflower is still one of the more reliable fall crops. It also stores well refrigerated, which is why cauliflower is easy to find in grocery stores during the winter.
5. 5. Collard greens: A close relative of kale, collard greens are regional to the United States South, where the winters are mild. But collard greens can handle when temperatures dip below freezing, too.
6. 6. Kale: A popular cold-weather crop, kale can handle a light frost. You can enjoy multiple harvests throughout the fall and early winter if you plant kale roughly six to eight weeks before the anticipated first frost. A light frost can make a kale crop sweeter.
7. 7. Kohlrabi: A sweeter relative of the turnip, kohlrabi is a cool-season crop that grows best in temperatures between forty degrees and seventy-five degrees Fahrenheit. Plant kohlrabi in the late summer and harvest in the fall.
8. 8. Leeks: Able to tolerate frozen soil, leeks might even survive temperatures as low as twenty degrees Fahrenheit. Leeks ripen reliably in the late fall, and growers harvest them into the winter.
9. 9. Peas: You can plant peas at the end of summer as a cool-season crop to harvest in the fall, or you can plant peas in the very early spring, when the ground is still cold but the last frost has passed.
10. 10. Turnips: A reliable winter crop, turnips roast well alongside other heirloom winter vegetables, or you can purée them into a soup. Plant turnips in your garden bed around mid-autumn to ensure a winter harvest.

You can keep your cool-season crops and frost-tender plants alive through the cold winter months and avoid frost damage if you follow a few key gardening tips:

1. 1. Be mindful of frost dates. Research your area’s frost dates (the last date in the spring or the first date in the fall that’s likely to see a frost). Watch the weather forecast for the threat of frost and be wary of sudden cold snaps with freezing temperatures or temperature drops. A window for planting cool-season crops opens up in late summer and early fall. Once mature, many of these crops can actually survive a light frost—in mild climates, they may even continue producing into the winter months.
2. 2. Cover large groups of plants. You can protect a group of plants by covering them with a blanket, bed sheet, or drop cloths. Be gentle when you drape the fabric over the plants and be sure to stake down the sides so it doesn’t blow away. You can also use a sheet of plastic or plastic sheeting as a row cover or plant cover.
3. 3. Have a plan for your tender plants. If you have frost-sensitive plants or other outdoor plants that won’t survive the winter, plan ahead so that you have a small greenhouse or other place ready indoors where they can stay for a few months alongside your houseplants.
4. 4. Spread mulch to protect roots. If you layer it properly, mulch can protect your plants' roots from frost and excessive rain. Aim to mulch your crops before the first hard freeze.
5. 5. Use a cloche to cover smaller plants. A cloche is a bell-shaped cover that you can use to keep plants out of the cold air. Use one or more cloches to cover plants, trapping warm air for frost protection. You can also create a DIY cloche by cutting off the top of a milk jug or other bottle and placing it over your garden plant.
6. 6. Use a cold frame. Another name for a structure you build around your crops (or over a raised bed garden) to protect your precious vegetables from the elements is a cold frame. This has a transparent roof that shields your plants from excessive rain while still letting in light. If the cold frame can seal, you can trap ground heat inside, which can help your plants survive the winter.
7. 7. Wrap trees to insulate them. You can wrap the trunks of trees like fruit trees with a blanket, strips of burlap, cardboard, or towels to help them stay warm.

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