Growing Figs in Cold Climates
The winter is the bane of every northern gardener’s existence. We all would love to be able to grow the tropical fruits and vegetables but so little is able to withstand the -20 degree temperatures that it makes the task seem too daunting. One fruit that I tend to get a lot of questions on is the fig, which is from the Mediterranean region. Normally, when you hear that a plant is from the Mediterranean, it is assumed that it cannot be grown in the North without a greenhouse. However, not all plants in this region are built the same. Plants that are from higher elevations in temperate areas still need to be able to withstand the cold in one way or another.
One of the ways that plants deal with cold weather, and the primary focus of this blog, is through dormancy. Some plants have developed an ability to dramatically slow their metabolism when exposed to prolonged periods of cold temperature. This allows the plants to “pause” their growth and “hibernate” through the winter. However, plants need a way to know when it is safe to break this dormancy. Have you ever wondered why most plants in the North don’t get tricked by the February “false springs” and know to start growing a couple of months later? That is because they have not received enough chill hours to break dormancy.
Chill hours are the cumulative amount of hours the plant has been exposed between 45-32 degrees. Typically, the further north you go, the more chill hours are required for the native plants to feel confident that the winter is over. For example, a highbush blueberry can need up to 1000 chill hours before its buds will start to “leaf out”. This is also why some crops, like apples and blueberries, are much easier to grow in northern climates but are notoriously difficult for warm climates that don’t get winter. Did you know that figs also have a required chill hours? Even though it is a Mediterranean plant, it still benefits from the yearly seasonal cycle. However, figs only requires between 100-200 hours in order to recharge for the next season. But us northern gardeners can use this requirement to our advantage by using containers. Once a plant goes dormant, it can stay dormant for a surprisingly long time.
An important note with growing figs is the time it takes for the breba to ripen. Fruits that are adapted to colder climates, and thus shorter growing seasons, typically will grow and fruit much faster during the season. Figs from warmer climates have the luxury of longer growing seasons and can ripen much slower. A couple of options for the northern gardener are growing colder climate figs and to break the dormancy early.
A common misconception
A very popular variety in the North right now is the Chicago Hardy Fig, for very obvious reasons. However, a lot of people feel “duped” by this variety as it is not hardy in the way people assume. While the plant is generally hardy to 5b, the plant does not get this hardiness rating because the above-ground tissue can survive the winters, it is because the roots can survive the winter. Each year, the Chicago Hardy Fig will die back to the ground and sprout up from the roots in the Spring. However, the plant then needs to spend a lot of extra energy into recreating its trunk, which causes many to never have the energy to fully ripen fruit. This is why my preferred method to growing even hardy figs is in containers so that the main structure of the tree remains intact between seasons. The unfortunate side effect/blessing of this growing method is it means that even hardy varieties of figs will be grown in the same way as warmer varieties of figs. I prefer to move even my hardy figs out of dormancy early because it can take time but doesn’t require as much sunlight. If you have a sunny windowsill, this is perfect. By the time the plants start leafing out, it should be close enough to above freezing that you can transition the plants to outside. You can also check out next week’s blog on cheating extra growing season with container gardening.
Here is a good timeline for how to take care of your figs to still get fruit:
In the fall:
Let the fig stay outside and experience a few light frosts to allow the leaves to start wilting and initiate dormancy. If temperatures get below ~28 degrees for too long it can damage the wood of the tree.
The leaves don’t need to be fully off the tree, but should give with a gentle poke of the finger.
Move the container into a garage or shed, but preferably an attached garage.
In the winter:
Very little water is needed when the plant is dormant. Only water with a couple of splashes through the winter. Too much water can trick the plants into breaking dormancy.
(optional for hardier varieties, mandatory for warmer varieties) A month or two before the last frost date, move the fig to a bright windowsill to allow it to break dormancy early.
