Winter poses great challenges for plants, especially non-natives.
Potted evergreens can be especially vulnerable in pots, where they don’t get the same insulation that occurs to their roots when planted deep in the ground, but they certainly can survive cold falls and winters by preparing your plant following some steps.
Aren’t Evergreens Supposed to be Ever Green?
If you live in a part of the country with cold winters you’ve likely seen evergreen trees before.
These trees have needles rather than leaves and they remain green all year long, for example, your traditional Christmas tree is an evergreen tree.
So yes, the evergreens should survive cold falls and winters, gold falls and winters but the main difference is the pot.
Once dirt is something in the ground it has lots and lots of drainage. Plus it also provides insulation for trees and helps prevent temperature fluctuations and roots from freezing.
Evergreen roots have good insulation because of the needle blanket that falls throughout the year. The ground protects the roots so that they do not experience the cold.
In a pot – The roots don’t have nearly the same amount of insulation or drainage AR/NE in the ground provide.
This is what presents the challenge. With too much water the roots will rot and freeze. This prevents the plant from taking up the water and nutrients it needs.
This doesn’t sound very hopeful that a potted evergreen will survive, but we have steps you can undertake to prepare your plant, and here they are.
Step-By-Step Guide to Preparing a Potted Evergreen for Cold Falls and Winters
Here are all the steps you can take to help your potted evergreen survive the cold.
Step 1: Choose the Right Evergreen
There are many varieties of evergreens available, but not many of them will do well in a pot.
If you want your evergreen to survive in your pot through the cold of fall and winter, your best bets are:
- Arborvitae: USDA zones 3-8
- Boxwood: USDA zones 4-9
- Dwarf Blue Spruce: USDA zones 2-8
- Dwarf Mugo Pine: USDA zones 3-7
- Juniper: USDA zones 2-7
When selecting an evergreen, make sure to notice what USDA growing zone they do the best in.
You are going to want to choose something that can survive in a lower USDA zone than you happen to be in.
For instance – if you live in zone 3, take the Dwarf Blue Spruce or Juniper evergreen. If you don’t know your USDA growing zone, you can take a look here.
You do this to help compensate for the temperature difference, as the roots will be exposed, where they are not planted in the ground and, therefore, do not have that insulation.
Step 2: Choose the Right Pot
When you’ve decided on the right evergreen for your pot, it’s time to choose the right pot.
There are a few things you’ll want to consider when picking out the pot such as:
- Size: Ensure the pot has enough room for the tree’s root ball to fit in comfortably. If it’s too small, the roots will stress each other out as their area is overcrowded. If it’s too large, the tree will have trouble staying hydrated.
- Material: You will want to make sure the pot is made of a material that insulates the roots (ceramic, metal, stone). Avoid plastic or terracotta pots, they do not insulate roots well.
- Drainage: You will want to make sure there are drainage holes at the bottom of the pot. You want to ensure the roots do not get too wet (which can lead to rot) and you do not want to have standing water that will freeze before the pot is completely dry since freezing water at the roots is damaging.
Step 3: Insulate Your Pot
Now that you have picked the ideal pot, it’s time to insulate the pot.
This will help keep the roots insulated from cold fall and winter temperatures.
There are two wonderful options to do this.
- You can take some sheets of Styrofoam and line the bottom and sides of the pot before adding dirt.
- Put your pot into a larger pot and fill the extra space with straw.
Step 4: Add a Heavy Layer of Mulch
Now that the pot is insulated and the plant is in the pot, it is now time to create a layer of mulch on top of the dirt.
If you have ever walked a trail in a forest of evergreens you may have noticed a layer of pine needles on the ground.
This is there to protect the roots of the trees from the cold; you want to do just that for your potted evergreen.
The mulch layer will also help to insulate the roots just like in the forest, and it will help keep them warm all winter long.
Step 5: Water When Dry on Warm Days
Even in the dead of winter when the temperature may be below freezing, evergreens will need to be watered.
While it can be a little tricky with the cold, don’t worry – you won’t need to do this very often. Usually when it is cold, the plant already has a nice blanket of moisture in the form of snow.
Even dirt inside a very insulated pot will give off some warmth. As it warms up, the snow, which is near or against the mulch, will start to softly melt, giving your plant a little moisture.
You will need to wait for the right conditions, though, before watering the evergreen. You should not see any snow, the soil should feel dry, and it should be a somewhat mild winter day (not so cold that you have snotcicles).
Once you have these conditions lined up, all you may need is a quick, light watering for your plant until next time.
Step 6: Do Not Bring Inside
Even though you might think about it, don’t bring your evergreens indoors.
Evergreens require a cold period in order to experience their dormancy, so they grow the next year.
If you place your evergreen indoors, it will not only not receive any dormancy, but it will also be shocked from the drastic temperature change and may die.
Final Thoughts
Thus, there is no need to fret if you live in a location with cold winters!
Evergreens can still be located in appropriate pots and ensured they do not freeze completely.
If you follow these easy steps, the evergreen in its pot can survive the winter and be enjoyed for many years to come.