PREPARING FIGS FOR A COLD WINTER
They’re Not Tropical
Too many people think fig trees are tropical plants. They’re not. They’re subtropical plants and that’s one reason those of us living in cold winter climates can harvest fresh, ripe figs. In fact, fig trees like that little rest that cold weather offers them.
Here in Zone 5 (average winter lows of minus 10 to minus 20° F), I grow figs a number of ways. Figs are cold hardy to the low ‘teens, too cold for even subtropical plants to grow outdoors in the ground, their stems splayed to cold winter air like my apples and pears. Their roots, especially if mulched, generally will survive winters here in the relatively warmer temperatures underground. But then new shoot growth must originate at ground level, and the growing season isn’t long enough for figs that develop on those shoots to ripen.
Potted
Some of my figs, like many of yours, are in pots.
With nighttime temperatures now often below freezing, there’s an urge to grab the potted fig and carry it indoors. Don’t! As I wrote, fig trees like a little cold weather. Experiencing some cold weather also toughens them to be more able to withstand even colder weather. My goal is to get these potted plants into a deep sleep, and to maintain that state as long as possible through winter, ideally until they’re ready to be carried outdoors again in spring.
If temperatures are going to be super cold, below the low ‘teens, move the plant to a temporary, but cool, location such as an unheated garage or mudroom, or garden shed.
Plants might still sport some leaves this time of year. Perhaps some of those leaves have been frosted. Not to worry.
Eventually, a potted fig needs to be moved to a winter home. Around here, at least, not yet. Typically, I leave my potted fig trees outside — in a slightly sheltered spot near a wall of my home where temperatures are modulated — until sometime in December. A fully dormant fig tree sheds its leaves so won’t need light in winter. If any of my plants are still holding onto their leaves, I just pull them off before the plants move to their winter home.
The winter home should be cold, but not frigid, ideally 30 to 45°F. That previously mentioned unheated garage or mudroom, or garden shed might be suitable. A minimum-maximum thermometer is an inexpensive way to know just how cold a site gets during winter even when you’re not in there or looking — at 2 AM, for example.
Some of my potted figs retire to my basement for winter, where winter temperatures are usually 40 to 45°F.
More recently, I’ve set up an insulated, walk-in cooler, mostly for storing fruits and vegetables. There’s also plenty of space for some potted fig trees. The cooler, which needs a little heat in the dead of winter, maintains a pretty consistent temperature of 39° F.
To help the plants remain asleep, I keep them on the dry side, perhaps watering them once or twice during this period.
To a point, the more stem growth on a fig tree, the more fruit it bears. So a potted fig can only bear so much fruit. I want more figs from some of my trees.
Innovations for Greater Yields
Years ago, I built a greenhouse in which to grow cool-weather-loving salad stuff and greens such as lettuce, celery, kale, chard, arugula, mustard, mâche, and claytonia through winter. I soon realized that the hot summers and the cool (never below about 35°F) winters in the greenhouse mimicked the Mediterranean climate that figs call home. So I planted four fig trees right in the ground in the greenhouse. The vegetables don’t mind their figgy neighbors because they’re leafless in winter.
Those fig trees are more than just leafless in winter; they’re also pretty much stemless. Each tree is trained to have a short trunk off which grows one or two permanent, horizontal arms. (This method of training is called espalier.)
Fruits are borne on shoots that grow vertically from these arms. Tomorrow I’ll lop all those vertical shoots back to the arms. Next year, new shoots will bear fruits and be cut back next fall, and the year after that, new shoots . . . and so on.
I’ve even used this method, this time with the horizontal arm trained just a few inches above ground level, for a fig tree I have growing outside. That low-growing arm is easily covered with a blanket of leaves, straw, or some other insulating material, how much depends on the depth of wither cold expected.
Once again, I’ll delay covering the plant until colder temperatures arrive so that the plant is hardened more against cold and goes into winter as dormant as possible.
Over the years, other figs of mine have weathered cold winters also by such methods as being bent over and covered to keep them warm and outdoors, by being grown in pots sunk into the ground then lifted, before the arrival of frigid weather. etc., etc. You want to harvest fresh figs in summer? There are many paths to this mountaintop.
The takeaway today is: Don’t protect your fig tree from too much cold too soon. Let the plant experience and benefit from the sleep-inducing and hardiness that some exposure brings.
And if you want to know more about growing figs in cold climate — varieties, method details, pruning, accelerating ripening, potting mixes, and more — see my book with the eponymous title GROWING FIGS IN COLD CLIMATES (available from the usual sources as well as, signed, from my website).Here’s a very short video I made back in October about some methods of growing figs in cold climates and my new book: Fig video
How can I get a copy of your Growing Figs book? I live in Canada and have killed many potted figs. I’m dying to get it right!
Thanks,
Lesli
I guess from the usual online and actual stores. It should be available. Unfortunately, it’s prohibitively expensive for me to ship to Canada. But thanks for the interest.
Hello, I live in Seattle, WA. Zone 8A. I get 2 crops of figs from my four year old tree, planted outside, grows magnificently, handles cold and wind just fine thank you. Violette de Bordeaux
? I can get some edible figs from the first crop, they have gotten enough sun/heat to both grow and ripen. However the second crop of figs have not gotten either the sun or heat to grow or ripen. They are now small hard rocks on branches.
What do do with these figs? I have asked many fruit growers, read books, and I have yet to get a reasoned answer. Should I remove the figs from the branches ? By twisting them off? Cutting them off? Prune the branches w/figs again?
The fig has been pruned both last spring, she responded by growing out further.
She also got a fall trim, to keep her within ladder reach for me.
Has this happened to you ? What do you suggest ? I enjoy and love this tree.
I don’t want to hurt it by acting stupid. Please help.
My fig climate is very different from yours. Here, we get plenty of summer heat and sun, and a moderately long growing season, followed by bitter cold winters. As far as those unripe, main crop figs, I suggest removing all but the very smallest ones. The latter might hang on through winter and bear a very early crop. Quoting from Ira Condit’s THE FIG, “Sometimes late figs which do not mature in the fall remain on the tree over winter and ripen in early spring. These are called “phaggim” in Palestine. Lob Injir trees commonly carry in winter a few immature figs which may be easily mistaken for mamme caprifigs.”
Thank you for answer. I have been searching for fig tree information since I planted this tree. Going to look up Ira Condit.
Hi Lee, I got your fig book via Amazon.co.uk to Ireland – great reading.
Do you restrict roots for your figs planted in ground? Eg to restrict growth in your greenhouse. I’m thinking of planting figs in ground and wish to keep them relatively small. Could I plant inside large plastic pots, with a hole cut to allow roots to forage for water. I could prune roots if needed by digging to the hole.
Hi Conor, You could restrict roots with the pot in the ground. But even in the greenhouse, I don’t restrict the roots. I do have to restrict top growth, though, or the stems would grow through the ceiling. I’ve repeatedly read about British gardeners taking various measures to restrict fig roots. I can’t see any reason to do that. Why do you want to?
Hi Lee, thanks for the reply.
I want smallish outdoor fig trees for fruit in our Fig Region 3, cool summer cool winters. Many UK books and websites say figs will focus on vegetative growth if not root restricted (they don’t suggest pruning as an alternative). And I guess I’ve never questioned the idea (until now!). I have in mind to do some heavy pruning anyway for a breba crop: http://www.youtube.com/watch?v=RB0D_tuKgtQ
So I’m trying to figure out if I need to restrict roots – eg like the photo on page 45 of your book (plastic pot with roots growing through) although permanently in-ground in my case.
Fig growth will be related to the richness of your soil, and the amount of heat and sunlight it receives. My guess is that roots do not need to be restricted where you are, especially if you renewal prune the upper portion (which need not be too high, not as high as in the video) each year.
I recently listened to the episode of A Way to Garden in which you talked about figs. Margaret posed a question about soil near the end of the podcast and you mentioned coir as a substitute for peat moss but also said you haven’t had good results with it. I’m curious why. I’ve been using it quite a bit and consider it excellent, in fact, superior to peat moss. Maybe it’s a topic you could address in a future blog post. Thanks!
Thanks for the feedback. Perhaps I will revisit coir. Do you use it in the same proportions as you did peat moss?
I’ve used it in thirds with compost and vermiculite, equal proportions with perlite, and also 2/3 coir and 1/3 vermiculite. All have worked well. The latter two seem to essentially eliminate the risk of overwatering plants. The main difference (compared to peat) is that I rinse it thoroughly initially to ensure any salt it in has been removed. I also use a CaMg supplement when I feed plants. I haven’t found a plant that hasn’t done well in it. In particular, seedlings seem to love it which I guess isn’t surprising. I have not tried cuttings in it yet, but I plan on doing some hardwoods of goumis this winter, so I guess I’ll see.
Okay, I convinced that I need to try coir again, and pay more attention to responses. The ratios of ingredients you use are in line with what I use, except with peat. Except I use only perlite, never vermiculite. The latter can contain some asbestos and, over time, breaks down to lose its ability to help with drainage. My mix is 1/4 each compost, soil, perlite, and peat.
I had been under the impression that asbestos was found primarily in a single vermiculite mine in MT that was closed in 1990. I did a quick search and found this EPA fact sheet (https://www.epa.gov/sites/default/files/2020-02/documents/horticultural_vermiculite_fact_sheet_epa_705-g-2020-3162__0.pdf) which indicates that 15% of vermiculite tested from garden stores (in 2020) contained sufficient asbestos to quantify a percentage. I’ve always worn a mask and mixed it outdoors, but 15% is still 15% (though, I suppose 85% is also 85%). I made the switch because it seemed to work better than perlite for seedlings. Also, although I would have thought that it wouldn’t do as well as as perlite in a potting mix for more Mediterranean herbs like oregano, they seemed to prefer it, perhaps because I have them in terracotta pots that can dry out quickly in the summer.
I forgot to ask if vermiculite breaks down at a rate that’s meaningful, e.g., a year or two (rather than ten or more)? I suppose if it does, it provides some nutrients, though I’m not certain how much that matters.
I wonder if the reason I’ve had such good success with it is that it retains nutrients better than perlite. That’s not a concern for you because your compost provides sufficient nutrients, but I’ve been making less and less compost and instead watering potted plants with “tea” (most often a combination of comfrey, nettles, thistle, and grass clippings soaked in a barrel until it stinks “something fierce” and then I add some fresh urine for good measure).
Part of the reason I’ve veered away from compost is that I’ve done more of it in place by mulching with a combination of grass clippings and shredded cardboard (and, in the fall, leaves). Contrary to popular belief, I’ve never seen any evidence that decomposing material on the surface of the soil will rob N from plants, even when I’ve tucked kitchen waste under the mulch rather than tossing it on the compost pile. I did initially have some concern that I would need to use too thick of a layer of clippings to suppress weeds and it would then become matted and rain would roll off rather than penetrate through it, but adding leaves and shredded cardboard seems to have taken care of that problem.
My only concern is that I’m not providing enough nutrients to replenish what’s lost. I know you’ve mentioned that you’ve done the math on your plot and determined that X (was it an inch or two?) compost applied each year to your garden beds was more than sufficient. I usually put 3-4″ of clippings/compost on each bed 2-3 times from April through December, so 6-12″. If it was a compost pile, I guess I would expect the volume to be reduced by about 90%. If that ratio holds for “compost in-place,” then I figure I’ve been applying the equivalent of around a half-inch to an inch each year. I do also wonder if my lazy-man’s approach actually provides more nutrients, particularly in the summer, even if the compost-equivalent is less because whatever leaches out goes directly into the garden rather than in the soil beneath the compost pile.
Over time, vermiculite loses its porosity; that’s the main reason I prefer perlite (besides the asbestos issue).
You’re right, despite what many journalist write, mulching with even a very high C/N ratio material does not rob the soil of nitrogen. Decomposition takes place at the interface of the mulch and the soil and, over time, re-release of nitrogen is about the same as what’s tied up temporarily. Mixing that mulch into the soil will tie up nitrogen, albeit temporarily.
As far as not replenishing enough nutrients with your clippings/compost, plant growth should tell you if this is the case. Sir Alfred Howard, one of the inspirations for organic gardening and farming over 60 years ago, hypothesized that, over time, soil microbes in an organically rich soil would be able to quickly digest raw organic materials added to the surface, obviating further need for compost-making.
I don’t worry about nutrients washing out of my compost piles. It would take an enormous amount of water to leach through a 3 to 5 foot high compost. Also, I cover my compost piles as I finish building them.
I harvested ripe figs November 8 in eastern PA, 50 miles north of Philadelphia. I have long thought about espaliering some of the mature plants growing outdoors. Your valuable new book, all your books have been valuable, has encouraged me to do it this year. I considered erecting a low seasonal hoop house a couple of feet tall over the plants but if mulching very low plants is reliable I would do that. Would one method be more reliable than the other? Thank you.
I would do the hoophouse, but only if I also used it for vegetables in winter. Of course, if there was a rare, very cold winter (and rarer they are these days), the low, covered espalier would be more reliable. I harvested some ripe figs from my barely heated greenhouse a few days ago but they don’t taste that good this time of year, probably because of the combination of cooler temperatures and less light. Quality this time of year varies with variety also.
It’s useful for you to spread the info that figs benefit from experiencing full dormancy- my brother in Hawaii had the least vigorous fig tree I’ve ever seen as a result of never receiving that rest and I’ve often seen struggling fig trees brought indoors before they’ve even lost their leaves in our climate.
I have an unheated well-house where I store my two excessively productive fig trees. I just moved them there because the smallest wood seems to freeze if I wait for true hard frost (below 25F). I believe this may delay harvest.
One method, back when pianos were still popular, was just to put a piano box over a fig tree and cover it with a tarp (keep baited mice traps there). Heat from the ground is enough to protect the trees in a more or less normal winter. I used to use a fence ring piled with leaves to protect them. When I covered it with a tarp the wood would rot, but with just leaves it worked for the season or two I tried it before just moving trees into my well house. A mouse bait station is recommended.
I bring my trees out in early April but then have to protect them if a frost comes after they leaf out. However, it takes them a while to leaf out so this often isn’t necessary.
My trees are in Whitcomb in-ground grow bags which I pop out of the ground with a heavy spade.
Hi Alan, A well-house is perfect, except that most people don’t have one. I once tried protecting my outdoor fig within a 4 foot circle of fencing into which I piled wood shavings and then gave the whole thing a plastic cap to keep it dry. It should have worked, but didn’t. Stems froze to the ground. In the future, I’m going to report on my low-growing,, outdoor fig espalier.
I have never had a good winter storage solution for figs and have killed many nice little plants (Boston, zone 6). I am going to try your “leave in the ground and mulch the low arms” method. We have rabbits and voles. Do you recommend using tree wrap?
So glad to see this post – and I’m going to order your book.
Yes, tree wrap, I think, is repulsive to the rodents. I used hardware cloth (wire mesh) but it’s much harder to put on.
I think I’ll give figs a try this year and will probably swaddle/wrap mine with straw/leaves as insulation. I’m near Toronto along Lake Ontario. We tend to be sheltered from extreme lows (annual lows in line with 6b) although our monthly means are closer to a New York State zone 5b/6a.
Hi Lee, this article is very useful to me. I live in Boston. I have one six year old fig tree , Ficus Carica, which I turned into bonsai couple of years ago. I also have several trees air layered from that same tree, which are in a large pot with regular soil. I always took these trees inside my heated house during the winter when the temperature reaches about freezing and as a result they never bore fruit. I want to try something different this winter, so I will keep them outside till mid December and bring into unheated space after that. Just to clarify, what is maximum allowed temperature which will still allow dormancy? Is it 45°F? Asking because my basement is somewhat heated and probably not suitable. I’m thinking of putting it into unheated stair case which I think has a temperature of about 45 degrees in winter. Last question, is it better for three during dormancy to have no light at all or some indirect light? Thank you.
About 25-44° is right for keeping a fig dormant, although it’s also a function of soil moisture. Keep the soil on the dry side to keep the plants dormant. Light is not needed during dormancy. Not sure about figs, but with some plants lack of light might help keep them dormant longer.