18 Ways to Protect Your Potted Plants Outdoors in Winter

Fall is turning to an end, and the chilly winds of winters are already biting our hands, and our potted plants – that need protection! Especially tender varieties, and especially in containers, our green friends need to keep their roots warm when the harsh and freezing days ahead come, and sometimes, their branches too! Sub zero temperatures can cause serious damage to them, and they may even kill them!

Of course, you can take them indoors, but how about if the pots are too big, or if you have no room?

There are many ways you can protect your tender potted plants from the cold of winter, from wrapping the containers themselves, to using plant covers, but it depends on many factors, like the size, the variety, and even the aesthetic needs of your garden or terrace!

So, here are a few easy tips to wrap up warm your potted plants, for all needs, and for all pockets!

Which Potted Plants You Should Shelter for Winter

First of all, a few words on which potted plants you need to protect for winter, so you don’t waste work and time on those that don’t. Here are basic guidelines then:

• All tender plants; by this, we mean plants that are not cold hardy to your USDA zone, which you can check out here.
• Exotic, tropical and subtropical potted plants, in all temperate, transition and cold regions.
• All potted plants that are just about hardy to your USDA hardiness zone; in containers, their roots get colder than in the soil.
• All seedlings; and there are many we grow in fall and winter, especially for vegetable gardens.
• All young plants that are not very cold hardy;I would suggest that, for a young potted plant, you should protect it even if it is hardy to your USDA zone and the one above.
• You could also add potted plants that are weak and sick, or have just recovered from an ailment.

And now, off with 16 great tips to keep them warm and healthy over winter!

Tip 1 – Prune All the Potted Plants That Need Pruning

The first step is, of course, to prune all the potted plants that need pruning during fall, so, come winter, they have fewer branches, and fewer places and tissue that can receive the cold and wind that this season brings.

This also helps you move them, shelter them, or, in case cover them!

Tip 2 – Mulch Your Potted Plants to Protect Them from Cold Winters

Have you been mulching your garden in fall? Good, but you can also spare some mulch for your potted plants. It will not have the full effect it has in vegetable or flower beds, borders etc., but that layer will partially insulate the soil and roots that are in your containers…

However, the sides of the pots receive cold and also humidity, if they are porous (like clay, or wood…). So, while this will help, don’t think that it is enough for tender plant varieties.

Tip 3 – Remove All the Saucers to Keep Your Potted Plants’ Feet Dry

Plants need less water in winter, when it often rains a lot, and saucers can fill with water, with tow negative consequences for your potted plants:

• They can get stagnant water, which can cause root rot.
• The water in the saucer may freeze!

So, before winter arrives, remove all the saucers from your potted plants!

Tip 4 – Move Your Potted Plants from Tiles, Paving Stones etc. and onto the Soil!

Stones and tiles do not hold the heat well, while the soil does. So, if you move your potted plants so they rest on the ground, they will get less cold coming from underneath.

An alternative could be to move them onto wood, or another insulating but warmth retentive material (even sawdust, for example).

Tip 5 – Only Water Your Potted Plants in the Morning During Winter

We usually water in the evening, so the soil retains it overnight. But in winter, you need to switch to morning watering. This is because you want the soil to absorb as much humidity as possible before temperatures drop, and it can become ice if it is still in the surface.

Then again, also remember to reduce watering, and in many cases, you may need to stop it altogether (depending on precipitations and the type of plant you have).

Tip 6 – Move Your Potted Plants to a More Sheltered Position for Winter

Potted plants are particularly at risk from the wind, wet and cold of winter if they are in an exposed position. On the other hand, moving them to a sheltered spot may be enough to protect them from this harsh season.

Place them neara wall that protects them from the prevailing winds. These usually come from the north in winter, so, if you move your potted plants to the south side of a wall, they will get plenty of sunlight and less rainy and windy weather, and higher temperatures too!

Move them under trees, or under a porch, or even next to your home, where your potted plants will benefit from the heat you too enjoy in winter!

But for more tender plant varieties in pots, and in very cold climates, this may not be enough protection, so…

Tip 7 – Gather Small Potted Plants Together, So They Keep Warm in Winter

If you have many small potted plants scattered all over your terrace or balcony, pick them up, choosea sheltered place and put them all close together. This alone will keep the warmer, like penguins do, to make it simple.

I suggest you place them under a roof, or in a place where they do not get heavy rains, or humidity will collect more easily in your group of small potted plants… Even a makeshift structure will do.

If you do, however, choose more hardy varieties to place on the outsides of this group…

But then you can add another barrier for your container plants against the cold and wind of winter…

Tip 8 – Insulate Your Grouped Small Container Plants and They Will Be Safer in Winter

Now you have grouped all the small potted plants together, maybe against a south facing wall, you can give them extra protection with an insulating layer around them.

You can use anything that keeps them warm, like straw, or wood chips, or even planks of wood to form an impromptu “box” or “raised bed”. Even wood logs will offer protection, or bricks, stones etc. if you want this “winter pot garden” to look beautiful…

Also stick some straw etc. in the gaps between the pots.

But how about if you want this group of potted plants to still look attractive over winter? Ideally, then, you can use cheaper materials between the gaps of the containers and wood bark, to surround them all… But it can become costly, if you have many little pots…

In this case, use a cheaper insulator (straw, wood chipping, even compost) to do most of the job, and then cover it with attractive bark!

Tip 9 – Wrap Up Your Containers Individually in a Cheap, Simple but Effective Way (But Not So Beautiful)

For larger containers, you can wrap them up individually, and now we will look at those that don’t need to be attractive during the winter season, maybe those at the back of your garden…

You need to protect the containers from both cold and rain. Yes, because if your coating gets wet and it freezes, it ends up lowering the temperature in the soil, not heating it!

Choose an insulating material, anything from an old blanket to straw, foam rubber etc. and wrap it round the container. You can use a string to tie it up.

Then, use a waterproof material, like plastic, to wrap the whole up. This way, you will keep your potted plants both warm and dry!

By the way, I find bubble wrap is the best “outer coating” for my potted plants, it insulates from humidity, but it also offers another protection from the cold. And it’s not too ugly!

Tip 10 – An Easy-Peasy Way to Wrap up Small and Medium Sized Containers for Winter

I am lazy, so, with small and medium sized potted plants, those I can lift easily, I cut a few corners…

I get a plasticbag, even a carrier bag. I cut a big hole in the bottom, and I put it where I want to shelter my potted plant.

Then, I put a few stones, or bricks at the bottom, making a flat layer (this is for drainage).

Then I fill it in with insulating material (straw, sawdust, and if I have some, expanded clay, I will re use it in spring…).

Then I simply push the pot into it, and I tie the bag round it with string. Easy peasy, cheap, but not so good looking…

Tip 11 – How to Make Your Wrapped Potted Plants Look Beautiful over Winter

So far we have seen ways to protect our potted plants from the harsh weather of winter, but we have not thought about the aesthetics of it… Plastic bags and sheet look really unattractive in a garden, and they are fine if they are not in full view, but maybe you want your main, front garden containers to look pretty?

Then, you can wrap them again! This time though, use burlap, or another pleasant looking material which is also tough.

Instead of wrapping it tight, leave it loose, with folds, like a present… And finally, use a big string, quite visible, to fasten it but also to form large loops, and your container will still look attractive, and with winter and Christmas theme as well!

Tip 12 – Put Smaller Pots within Bigger Pots for Winter

This is another trick I have come across, which I find very easy and practical, but of course, you need to have spare containers to do this…

Place your potted plant in a bigger container and, if it is clay, this alone will give a double protection to the roots.

But this does not work with plastic pots, and, in any case, to give them extra warmth, fill in the empty space between the two containers with sawdust, straw, wood chips or even compost, or soil. But cover this gap at the top with a waterproof material.

Alternatively, if you have expanded clay, it would be the ideal material to use for this method, and even polystyrenechips will do, though they can become a mess to clean up in spring…

Tip 13 – Plant Your Containers Plants in the Soil – Pot and All!

This tip is handy if you have a corner in your garden that you are not going to use during winter. You can simply plant you container plants in the soil, with their pots!

You can do this for individual pots or groups, digging a hole that is at least 4 (10 cm)inches deeper than the pots, putting gravel at the bottom, and then placing the pot(s) in top.

Seal any gaps with the soil you have removed, and mulch! Now you have buried the pots!

Of course, this only works for plant varieties that are cold hardy to your USDA zone in the soil, but not in containers…

And now we have looked at all the ways you have to keep the roots of your potted plants safe, let’s move up, to the stems and branches…

Tip 14 – A Very Simple Way to Protect Small Potted Plants from the Cold of Winter

For more tender varieties, you will also want to protect the aerial part, what is above ground. For very small plants, once you have wrapped the pot and mulched, you can simply cut the bottom of a transparent plastic bottle (not colored!) remove the cap and stick it on top of them.

This is also useful for seedlings you plant in your winter vegetable garden…

But of course, it doesn’t work for bigger plants…

Tip 15 – Use a Plant Cover to Protect Your Potted Beauties from Winter

There are many plant covers, of different sizes and costs; some are little more than plastic bags, others are domes, like igloo tents, others are cones… You can choose the ones that nest fit your varieties.

But before you actually put them under a cover, you should give your potted plants a generous spraying with a natural fungicide, because enclosed environments, warmth and the humidity they trap are a breeding ground for them.

A teaspoon of neem oil per liter of water is plenty, and you can melt in some natural soap to make it stick longer. Spray your potted plants very thoroughly, and also the containers themselves.

Then, always remember to check all the plants you have under cover for diseases during the winter season!

Tip 16 – Make Your Own Plant Cover to Protect Your Potted Varieties in Winter

If you have lots of potted plants, and big varieties as well, buying plant covers can become expensive. But you can always make your own.

You will need to form a frame, either a dome, or a pyramid, or even a tunnel, of course, with anything from bamboo sticks to iron or even with chicken wire…

But the important thing is that you choose a plastic sheet (cellophane for lighter jobs, polythene for better protection) that is fully transparent and that you place some breathing holes in them.

For the rest, treat your potted plants as if they were under expensive bought covers…

Tip 17 – Buy or Make a Polytunnel to Shelter Your Potted Plants Over Winter

We can wrap it all up with a polytunnel! This is by far the easiest solution when you have a few potted plants to shelter for winter. And in a way, it sums up many of the methods we have seen so far.

You can gather all your container plants in one place, if you want, you can add insulating material between the pots, or plant them in the soil, or wrap them individually etc…

Then, give them a good neem oil spray, and finally put them under your polytunnel. Small ones are very cheap, starting at about $15 each. Bigger ones are, naturally, more expensive.

If you have lots of potted plants, and bigger ones, you can make your own. You can simply buy a sheet of polythene, and then you will need some hoops to stick in the soil at a regular distance (never more than 3 feet or a meter). Any fairly durable material will do, iron, plastic or cheap wood…

Cover it and fix the polythene sheet to the floor with stones or bricks.

But remember to ventilate it at least once a day, opening the ends, and finally… Remember to place it with the longest side running from north to south! This way, it will get most of the sunlight and heat!

Tip 18 – Use Straw to Raise the Temperature Inside Plant Covers and Polytunnels

And here is a final tip for you. Mulch is all good, but different types of mulch have different qualities, and straw is the best to withhold heat… So, if you want your plant covers or polytunnels use it as mulch, to wrap and insulate, and your potted plants will keep nice and warm all through the winter season!