Winterizing plants can take different forms depending on your climate and the plants you need to protect. Regardless, it often involves keeping them warm and protecting them from frost and snow.
In this article, we’ll cover how to winterize plants, including how to winterize potted plants. First, let’s look at why you might need to do this.
Winterizing plants is done for one simple reason: to stop them from dying. Most plants will go into hibernation in colder months, which can involve them dropping their leaves or simply not growing.
However, some plants benefit from a bit of extra protection, particularly if they’re not suited to your specific climate. Plants have varying levels of resistance to cold and frost, but obviously something meant for a tropical climate won’t do well in a freezing northern winter!
Winterizing plants should be done before cold weather properly sets in, which varies based on your area. However, a general rule is that you should have your plants winterized before the first frost happens. This means winterizing plants is often done in fall ready for winter, as a bit of extra padding won’t hurt them before temperatures drop.
Unfortunately, there isn’t really an exact temperature guide for when to winterize plants. A general rule to follow is that they should be protected by the time temperatures reach 40F (around 4.5C). In turn, you can remove the winter protection once temperatures increase to this level.
You shouldn’t need to do anything if your winter temperature doesn’t reach freezing. Cold weather is fine – most plants can tolerate a bit of cold. Frost and snow are the real issues, as these can kill off roots.
This is what winterizing plants often means: protecting roots from freezing temperatures. Pretty much all plants can recover from losing stems and leaves, but few will come back to life if their root ball dies.
The extent of your winterizing efforts will depend on the plants you’re trying to protect. Very delicate plants will need the most help, whereas hardy plants can be left almost completely alone. We won’t cover every plant you might have in your garden, but the suggestions below will include some plants they’re suitable for.
Winterizing potted plants is often more important than those planted directly in the ground. This is because their roots are more prone to frost damage due to the lack of insulation. However, some pots (such as plastic) are better insulators than stone or terracotta.
Climbing or trailing plants can be difficult to winterize if they’re fairly big. In these situations, focus on the roots rather than the stems because these can recover more easily.
The easiest way to know whether a specific plant needs to be winterized is to think about its growing conditions. First, if it’s a tropical plant, it’ll definitely need help. This might include houseplants, citrus trees, and so on. Also, a plant’s label should say whether it can tolerate frost, so check this when you buy it.
On the other hand, evergreens shouldn’t need any help. Hardy fruit trees, such as apple and pear, will be fine over winter too. But if your weather gets really cold (and snowy), consider just focusing on plants that’ll survive a snowy winter.
When it comes to winterizing potted plants, the easiest thing to do is wrap the pot. One of the best materials to use is hessian because it’s a decent insulator. If you don’t want to spend much money, bubble wrap works well too.
If your weather is due to get really cold, you should also consider adding blankets around the pot. Your goal is to insulate the pot enough that the soil won’t freeze, which should keep the roots alive.
Mulching is another good option for how to winterize potted plants, but it helps with any plants in soil. Mulch is essentially organic matter that helps keep moisture in the soil while also providing a layer of insulation. This theoretically prevents it from freezing over.
Some good mulch materials include:
- Palm tree leaves
- Fern leaves
- Conifer branches
- Wood chips
In short, you want anything that’s got quite a lot of volume to it, as this keeps a layer of air over the soil. Avoid dense or hard materials like pebbles or gravel. Your mulch layer should be 2-3 inches thick at least.
One of the easiest ways to winterize hanging plants is to bury them in the ground. Of course, this won’t work for balcony hanging plants. For those, just wrap the pots as described above.
But if you have a backyard and you’re worried about your hanging plants, just bury them in the ground. Dig a hole big enough for the pot, pop it in, and put mulch on top. Avoid burying it under soil, as this can make it difficult to dig up.
Some plants won’t appreciate being wrapped up, as they’ll still need air and humidity. For example, bougainvillea, oleander, and citrus trees need decent humidity and air circulation.
The easiest way to get around this is by using a greenhouse. A greenhouse can help keep the temperature above freezing while still providing enough light and air. A balcony greenhouse is a good option because most are collapsible if you don’t need them all year. Alternatively, you could make your own.
If humidity isn’t as much of a concern, the easiest thing to do is to bring your plants inside. This is suitable for winterizing plants that are considered houseplants, such as succulents, spider plants, pothos, etc.
Of course, it means having space for them indoors. If you can, group them together in a corner near a window. This’ll help keep humidity up. Even plants that don’t need high humidity can suffer indoors in the winter because heated air is much drier.
The main benefit of this option is that it’s free – you just need enough room for your plants. Don’t bring in actual outdoor plants, such as ferns, conifers, etc., as they don’t like indoor temperatures.
For larger trees, especially palms or other tropical trees, wrapping their trunks helps prevent sunscald and frost damage. You won’t need to do this for native plants or evergreens, though.
Plant covers (such as these) work well, but burlap, hessian, or even blankets are all good alternatives. As with wrapping pots, the goal is to just provide a layer of protection, so it doesn’t need to be too thick.
Ornamental trees or shrubs might need leaf protection, whether they’re deciduous or evergreen. The biggest danger to perennial trees and shrubs is alternating freezing and thawing days combined with strong wind. It can result in them losing leaves, which could cause them to die.
Frost protection bags (such as these) do a good job. Don’t worry about them not being translucent, as most will let in enough light for your plants to stay alive. That said, if they go into hibernation in the winter, this doesn’t matter.
Any of the ideas above are suitable for winterizing plants. Which you use will depend on where (and how) your plants are growing and the extent of protection they need. Regardless, winterizing plants isn’t a difficult process and helps keep them alive for another year.