7 Ways to Protect Your Fruit Trees From Freezing Temperatures

If you’re a gardener, you must be paying attention to the winter weather forecasts. Unusually cold temperatures can be a novelty in the South, but they’re very familiar in the North. Perennials are typically planted based on their zone hardiness, but some can grow at the margins of their climate tolerances.

While this can extend your harvest timing and the overall diversity of crops, extreme winter weather can challenge trees and shrubs at the edge of their natural range. Fruit trees, in particular, can suffer from temperatures that fall below their usual threshold. 

Most mature stone fruits are tolerant of lower than average temperatures. Commonly indicated for a wide range of climates, many of these have roots that will endure a frosty spell. When it comes to citrus, things get more complicated. Young plants can also be more vulnerable to the weather. 

I’d love to share some of the ways I prepare my fruit trees for frosty winter weather. With a bit of extra attention, you can prep your plants for freezing weather. Even with extra care, you may see some effects, but those trees should bounce back when spring rolls around. 

Give Special Attention to Young Trees

First and foremost, if you have limited time and resources, focus on your young trees. These are far more vulnerable to freezing temperatures than those mature and established in the garden. Any newly planted fruit trees will need the most care. Fortunately, they will still be fairly small at this point, so there is more you can do to protect them.

These have the most vulnerable roots, which are the most important part when it comes to cold exposure. The earth remains warmer than the air as long as there are no air pockets, which are more common with newly planted trees. You may see some damage to the branches, but if the roots can tolerate the cold, you won’t have a complete loss. 

Fill in Any Cracks in the Soil

Even in much colder climates, the soil typically stays warmer than the surrounding air in winter. This is what enables us to grow things that may be just on the cusp of tolerating our climate. 

Here in Zone 9, I am able to grow many tropical plants. However, the foliage dies back over the winter months. They return in the spring, and as their root systems expand, they tend to come back larger and more robust each year. The reason this happens is due to that phenomenon where the earth remains warmer than the surrounding air. 

The exception to this is when air pockets remain in the soil around the roots. These air pockets can fill with that frigid air, holding it against your tree’s roots, causing more damage than the surrounding soil would. 

When you plant your trees, it’s important to tamp down the dirt to work out these air pockets. However, that doesn’t always do it. Over time, you may notice areas of soil have caved into these areas. If you see cracks around the base of your trunk, fill these in with soil and tamp down to work that air out. 

Hold Off On Pruning

Winter is a good time for pruning many fruit trees. Pruning while they are dormant allows you to see the shape and identify which branches to leave and which to remove to create an ideal shape. For the most part, as long as it is fully dormant, the cold won’t do much damage. Timing is important here. 

If you prune too soon, and it produces new growth, that new growth will be extra vulnerable to cold damage. It’s not a good time to trim immediately before a cold snap. Your plant needs time to heal over those cuts, or they, too, will be more vulnerable to cold damage.

Protect your fruit trees from freezing by timing your pruning for a week with milder weather rather than one that could welcome the arrival of a cold front. This is not absolutely vital, but it will help to offer the tree an extra layer of protection. A good rule of thumb for many fruit trees it to prune as soon as buds are fully formed.

Water Heavily

Remember those air pockets that can hold cold air around the roots of your tree? Well, dry soil does something similar. Cold air is better able to penetrate dry soil, so dry soil will be colder than moist soil. 

If you’re expecting a major temperature drop overnight, make use of the daytime to give your soil a good long soak. Make sure to water when the temperature is at least 40°F (4°C). Water early in the day, and thoroughly soak the area around the plant you want to protect. 

Make sure to keep up with watering through the winter, especially if you have long periods of dry weather. That dry soil is stressful for the roots, and prolonged exposure can be deadly. Water twice a month, and water deeply. You want the soil moist all the way to the outer reaches of the roots. 

Mulch Generously

One of the most effective ways to protect young fruit trees from freezing weather is to add mulch. Just as in the summer, mulch holds moisture in the soil. We talked about how moist soil stays warmer than dry, and this is a great way to keep that moisture where it needs to be. 

But mulch doesn’t just help by holding in moisture. It also holds heat in the soil. Here’s the catch: it’s important to apply the mulch when the soil is already nice and toasty. If you have a few warm days going into that cold snap, use the time to lay on the mulch. 

Create a donut of mulch around the trunk, and cover as far out as you expect the roots to be. Typically, this will be around the same reach as the drip line. Layer it on thick. A four to six-inch blanket will keep things nice and toasty. Don’t press it up against the trunk; this is what I mean by creating a donut. Leave a few inches of space right around the trunk. 

Wrap Trunks

Young fruit trees have thin, fragile bark that doesn’t protect them much from a freeze. While wrapping mature trees is not a great idea, wrapping the young ones can be helpful in cold weather. Use strips of burlap or craft paper, holding it in place with tape or twine. 

Now, this may not have much scientific research to back it up, but it’s something I’ve done on occasion when we are expecting a cold front. I like to wrap the more vulnerable trees with a string of Christmas lights to create some additional warmth. You have to use the old-timey incandescent lights because the LED type doesn’t generate heat. 

Don’t wrap your lights too tightly, and don’t leave them there all season if possible. The weight can be stressful, especially on young, delicate branches. Just leave them on long enough to get through the frigid temperatures. 

Another benefit of wrapping trunks is the protection of that delicate bark from the sun. In winter, when your deciduous plants lose their leaves, it’s easy to stop worrying about them. As a result of losing their leaves, their bark gets a lot more sun exposure, which can burn it. 

It’s good to wrap those young trees the first couple of winters, regardless of the temperature. You can use burlap or paper, or there are commercial plastic guards available for this purpose. Some people paint their trunks with white paint, which works, but then you have a painted trunk. 

Cover Up if Possible

For larger, established trees, there is little else you can do at this point. But, for those young fruit trees, there is one more way to protect them from a freeze and make a significant difference. If your tree is small enough, it’s a good idea to get some frost cloth and cover them. 

Frost cloth is lightweight and breathable, but it prevents dew from falling on the branches and freezing. If you waited too long and either can’t locate these or don’t have time to go get them, bedsheets will offer some protection. 

Aftercare

Once the cold weather passes, you’ll have some recovery work to handle. The first thing to do is water again. Give your plants a long drink to help them recover from the stress of that cold, dry air. This will jump-start the recovery process and get your trees on the path to bouncing back.

Wait a few days to see what, if any, damage has been done. Don’t set to work pruning just yet. For citrus trees, this can be troubling. Because they have evergreen foliage, it’s alarming to see their leaves turn yellow and fall off. If you get temperatures below what they typically tolerate, this is exactly what will happen. 

A few years ago, we had an intense cold spell during Christmas week. My poor lemon tree took a major beating. Every last leaf turned yellow and fell off. I thought it was a goner. Well, I didn’t wait long enough and set about pruning it back pretty hard. I must have cut it back by nearly half in an attempt to get to live wood. 

I’m happy to report that that tree is alive and well and produced a bounty of lovely lemons this winter. Sadly, by setting to work too early, I probably lost a lot of viable real estate. The moral of the story is, hold off on pruning. You’ll have a better picture of the damage when spring rolls in and new growth begins. 

Once the cold has passed and active growth resumes, think about giving a light application with a balanced fertilizer. This will help replenish lost stores and give your tree a boost going into its growing season. Once the new growth appears, you should be able to see where, and if any wood has been permanently damaged. This is the time to prune off dead and damaged branches.