How to Overwinter Potted Trees in a Cold Climate

Let Your Tree Sleep For The Winter

The example I’m using here is a potted fig tree, but the steps are essentially the same for any deciduous tree growing in a container.

• Overwintering a potted fig tree is a simple process that requires a bit of work in the fall before first frost, and then again in the spring before last frost.
• You will need a winter storage space like a garage where (ideally) the temperature stays between 0-10°C / 32 to 50° F.
• Many fig trees are hardy (can survive year round outdoors) in gardening zones 7 to 11. With these overwintering tips, you can keep them thriving in zones as low as 4.

When I first got my fig trees (Chicago Hardy fig, 6″ long including the roots, by mail order), at the end of their first growing season, I could not find any information about how to protect them during the winter months, so I basically made up the steps. As it turns out, my instincts were correct.

• Overwintering tells the tree to nap for the winter, protected from freezing temperatures and light.
• When last frost approaches in the spring, you take steps to ‘wake it up’ again, to be ready for a new growing season.
• If you are growing your fig tree in a container, you’ll want to remove the tree from the container every second year and prune the roots. This keeps the tree healthy and encourages fruiting and growth.

Related: How to overwinter geraniums (as houseplants or in cold storage).

Year One

In the fall, a few weeks before first frost

1. Ease off on watering as the weather gets cooler and let the tree experience some dips in temperature including light frosts.
2. Cooler temperatures makes the sap drop low in the tree and the leaves will yellow and start falling off (this is good).
3. Right before storing the tree, spray it with dormant oil (recipe below). This will kill off any pests.
4. When frosts are near, move the container to a garage (ideal temperature range is 0-10°C / 32 to 50° F).
5. Keep the plant in darkness (I put a big bag over mine).
6. Some people don’t water them at all. I water mine very lightly every 6 weeks or so if the soil is really dry (a sign it needs new soil).

In the spring, a few weeks before last frost

1. Start watering the plant again and gradually reintroduce it to sunlight.
2. Two weeks or so before last frost, place the tree outside, ideally in a warm spot. I put mine next to an exterior brick wall with southern exposure.
3. If you’re still having frosty nights, bring the tree inside at night or cover it with heavy row covers or frost cloths.
4. Within a few weeks you will see new growth, sprouts, and leaves.

Related: Cold Storage 101: Food Preservation Tips

Year Two

Potted fig trees need ‘root pruning’ approximately every two years.

In the fall, a few weeks before first frost

1. Remove the tree from the pot, and cut back the roots to a healthy ball.
2. Store the root ball in a plastic bag and keep the entire tree in a cool dark place for the winter (ideal temperature range is 0-10°C / 32 to 50° F ).
3. If you’re smart, you’ll have new potting soil, compost, and organic fertilizer all ready for re-potting in the spring.

A few weeks before last frost in the spring

1. Re-pot the tree in fresh potting soil (2 parts soilless mix to 1 part compost, plus granular organic fertilizer)
2. Water lightly. Prune away any dead branches.
3. Gradually reintroduce the tree to light.
4. Two weeks or so before last frost, place the tree outside, ideally in a warm spot. I put mine next to an exterior brick wall with southern exposure.
5. If you’re still having frosty nights, bring the tree inside at night or cover it with heavy row covers or frost cloths.

Within a few weeks you will see new growth, sprouts, and leaves.

Related: The Most Important Fall Garden Tasks.

Year Three

Same as Year One. Root prune again in Year Four.

Organic Dormant Oil

Recipe provided by Barb at Our Fairfield Home and Garden
Here’s the easy recipe for Organic Dormant Oil Spray : (Mix 2 Tbs ultrafine canola oil with 1 Tbs baking soda and a gallon of water in a container and shake well, then pour into a spray bottle to apply).

Mix these ingredients together, shake well, apply using spray bottle:

•  2 Tbs ultrafine canola oil
•  1 Tbs  baking soda
• a gallon of water

~Melissa the Empress of Dirt ♛