Fig trees (Ficus carica) thrive naturally in Mediterranean climates characterized by hot, dry summers and mild, wet winters. This heritage makes their survival a question for gardeners in regions that experience sustained freezing temperatures. Most common varieties are comfortable in USDA Hardiness Zones 8 through 11, where winter protection is rarely necessary. However, with specific knowledge and a proactive approach, these fruit-bearing trees can successfully overwinter in significantly colder climates, making it possible to enjoy home-grown figs even in northern latitudes.
Variables Affecting Winter Survival
A fig tree’s cold tolerance depends on genetics, age, and physical condition. Most fig varieties begin to suffer branch damage when temperatures drop below 15°F, with survival becoming highly unlikely below 5°F without intervention. Certain cultivars, such as ‘Chicago Hardy’ or ‘Celeste,’ possess greater resilience, allowing them to endure temperatures as low as -10°F when properly protected.
Maturity is a significant factor in cold tolerance; older, established trees possess thicker root systems capable of insulating against deep freezes. Younger trees are more vulnerable and require protection below 20°F. Lignification, the hardening and browning of the branches, prepares the wood for winter. Branches that remain green or succulent late into the fall are highly susceptible to freeze damage, regardless of the cultivar.
Techniques for Protecting In-Ground Trees
For fig trees planted in marginal climates (Zones 6 and 7), protective measures must be implemented after the tree enters full dormancy, typically following the first hard frost. Preparing the tree involves pruning away weak or diseased wood, then gently drawing the remaining branches together into a tight column using twine or rope. This bundling minimizes the surface area exposed to freezing winds and makes the subsequent wrapping process more manageable.
One popular method is constructing a “fig chimney” by wrapping the gathered tree in layers of burlap or frost fabric, then building a cylindrical cage of chicken wire around it. This cage is filled with insulating material such as shredded leaves or straw, trapping warmth generated by the earth. Cover the base of the tree with a thick layer of mulch, 6 to 12 inches deep, to insulate the root crown. The top of the wrapped structure should be left partially open or covered with a rain-shedding cap, like a plastic bucket, to prevent moisture accumulation, which can lead to rot and mold.
Alternatively, the “bend and cover” technique involves bending branches down and pinning them in place with garden staples. Once secured, the entire tree is covered with a heavy layer of insulating material, such as cardboard and mulch, or a thick tarp. This method takes advantage of the soil’s warmth, which is substantially higher than the air temperature during extreme cold events. Regardless of the technique chosen, moisture control is important, as wet insulation material loses its thermal properties and can promote fungal diseases on the bark.
Managing Container-Grown Figs
Growing figs in containers offers a simpler, effective method for ensuring winter survival, especially in Zones 5 and colder, because they can be moved indoors. The first step in fall management is allowing the tree to experience a few light frosts, which naturally triggers dormancy and causes the leaves to drop. Once dormant, the trees should be moved to a sheltered, unheated location that maintains a consistently cool temperature.
The ideal winter storage temperature range is between 30°F and 50°F, which is sufficient to keep the tree dormant without allowing the roots to freeze solid. Spaces like an unheated garage, a cool basement, or a root cellar work well because they buffer the extremes of outdoor temperatures. If the storage area becomes too warm, specifically above 45°F to 50°F for an extended period, the tree may prematurely break dormancy, leading to vulnerable new growth that can be damaged later.
During the dormant period, the tree requires minimal water, often just enough to prevent the soil from completely drying out and the roots from desiccating. Watering frequency may be as little as once per month, but the exact timing depends on the humidity and temperature of the storage environment. Fig trees in containers do not need light while dormant, making dark storage locations suitable.
Assessing Damage and Spring Recovery
Winter protection should be removed carefully in early spring, typically after the last hard frost has passed and night temperatures remain above 20°F. Uncovering the tree too early risks exposing tender growth to late-season freezes, while leaving the covering on too late can trap heat and moisture, encouraging mold or premature bud break. Once the wrappings are removed, the tree’s branches must be inspected for signs of winter damage.
Dead wood is usually identifiable by a blackened or reddish-brown coloration and a lack of swelling buds. Gardeners can perform a scratch test on questionable branches: if the tissue beneath the bark is green, the wood is alive; if it is brown or dry, it is dead. Pruning should focus on removing dead wood back to the point where green, live tissue is found, or back to the ground if the entire structure has died.
Even if the above-ground growth has completely died back, fig trees are resilient and often sprout vigorously from the root crown, a phenomenon known as “dieback and regrowth.” This new growth often produces a crop of figs in the same season, though it may be later than a crop from overwintered wood. Patience is important; if no growth appears by late spring, it is advisable to wait until early summer before concluding the tree did not survive.