I have a Chicago Hardy fig tree, in the attached photo, that I planted last spring. I know I'm on the edge of the climate where it will survive the winter, so I planted it in the most protected spot of the area available. Looking at it now, it looks like the tips of last year's growth definitely froze, but I think the tree is still alive.
My question is: how should I prune it? It was pruned when I bought it and none of the pruned branches had any new growth last year. I'm thinking at a minimum I should prune those off and prune back to where I think is the end of damaged areas on the new growth. Should I prune it back even further, such as back to the main limbs that new growth came off of last year? I've also seen people say to cut them back to the ground each year if you're growing them more as a bush then a tree, but I'm wondering if that would be applicable in cold climates with a shorter growing season. Any insign would be appreciated.
Chicago Hardy Figs are probably one of the most cold hardy figs. What makes them cold hardy, is the ability of the tree, to die back to the ground level from freezing, and regenerate all new growth in the next growing season, all while still being able to produce a main fall crop. Figs can produce two crops, the early berba crop, and the later main crop. Every type of fig is different in the way and time it produces, between these two cropping options. The berba crop is from small immature fruits pollinated and carried over from the previous year. While the fall crop often referred to as the main crop is all flowered and developed that same season. Some fig varieties only produce mainly berba crops. While the cold hardy varieties sometimes can produce berba crops, the cold doesn't allow the immature fruit to carry over winter, so the productive varieties must produce a strong main crop. If you're in an area that pushes the boundaries of what the woody tree tissue can handel temperature wise, the benefits of cutting your tree down to the ground in late fall and early winter. Is that you can mulch over the stump and roots to better protect them from cold. It also keeps the cut wounds smaller, and easier for the tree to close without rot issues. When pushing the boundaries of survival for the Chicago Hardy Fig, growing a bush styles fig tree is the only option, as the freeze will kill the previous years growth. Even if you successfully grow it tree style, at some point, unusually cold weather will cause sever damage, creating a bush like tree. The bush like tree is just the chemistry responce of continually bening cut back or frozen back. The annual fall cutting it down, is a preliminary way of dealing with the impending problem, while alowing you to mulch over the stump and roots for better cold protection and better regrowth the following spring. The tree will continue to grow stronger underground, and get better at regrowth with age.
If it were me in regards to your pruning questions, I would prune off only the dead. You can just trim off whats obviously dead, down to buds orientated to help it grow in a proper structure for this year. If your climate will allow your tree to grow as a tree, then grow it as a tree. But if complete die back is inevitable, I wouldn't let your trunk wood go much beyont this next growing season, before cutting it down. Mulch over the trunk and roots every fall to protect them, and know if it grows without the dormant fall cut back. At some point, you will most likely be cutting freeze damaged deadwood, down to the ground in spring. The yearly cutting back in late fall, is like pollarging at ground level, and when pollarging its important to do annual pruning, and when training, to keep the cuts not much bigger then 1 inch. Those principles help protect the heart wood from rot, but in this case its the underground trunk mass and root structure you want to protect from rot.
Thanks for the advice. I pruned it back to close the main branches and I'll plan to cutting it back to the ground this fall, once the season is over. No buds on it yet, but it looks like there was green wood in the less damaged branches I pruned.
Just a quick follow-up, if anyone is referencing this in the future. The growth from last year was dead, but I did get new growth from the roots, after the weather warmed up more. I cut the dead growth back close to the ground and it seems to be doing pretty well this year so far. It's about three foot tall and starting to get more bushy at the moment.
I'll be cutting it back to the ground and covering it once we've had a hard frost, but seeing as it came back this year with only minimal protection from last year's pretty cold winter, I feel more confident that it will be able to make it going forward.
You can, instead of cutting it back to the ground, cover it with a frost blanket and that will help the branches survive the winter.
If you don't want to do that, then leave the branches and just use an old sheet to cover the tree with, this will keep frost from killing the buds.
Almost all fig trees will have some die back in winter, the thicker and older the branches are, the better they survive, frost is usually harder on figs than just freezing temperatures so keeping some type of frost cover on them is always a good idea.
If your tree has to make a comeback from the roots, so be it, but it will become a wide spread bush like tree.