Fig tree winter survival 2018-2020

[hoosierbanana]

I’ve finished uncovering all my fig trees, hopefully frost danger has passed for the year. The only trees planted in the open that had good survival were those that were protected from frost with agribon in the fall, and then bent over to 3-4 ft. and covered more tightly with 2 or more layers of agribon.

Adriatic JH, 7 out of 10 trees only had minimal damage for the past 3 winter. 2 trees have died to the ground each year, and one that survived prior winters but died to the ground this winter. There seems to be no major issues with leaving the agribon on until danger of frost has passed, no fungal problems and aside from some scrunched leaves they are fine… It was probably 1o degrees hotter under the cover when I took it off today.

Also surviving well were 15+ MBVS which were also covered for frost and survived 1 prior winter. And 2 Longue d’Aouts, which were killed to the ground last winter but were covered for frost, the look to be about half dead. I see some life in others, though there seems to be no obvious correlation to variety, but I will get a better idea of that after pruning and will update with anything significant.

My take away: unless planted in a sheltered microclimate the single most important factor for fig tree winter survival is gradually entering dormancy, followed by a mature (less vigorous) growth habit.

[fruitnut]

@hoosierbanana

unless planted in a sheltered microclimate the single most important factor for fig tree winter survival is gradually entering dormancy,

That’s a big factor, not too cold to fast. Also temperatures that don’t fluctuate too much in winter.

I’m 7b/8a. It only dropped to 17F last winter. OK wait the 17 was the first freeze of the fall on Nov 13. It never got below 21 after that. I lost one plant and another was frozen back to ground level. Even the biggest fig around here at about 10ft tall is growing back from the ground. It’s on a hill with good cold air drainage and usually makes it thru winter with minor to moderate die back.

Given equal zones figs clearly do better with Eastern winters than on the plains.

[Ruben]

Where are you located at? @fruitnut

[fruitnut]

Alpine Texas at 4500 ft elevation. That’s west Texas at about 30 N latitude and a little west of the eastern border with New Mexico.

The plains and foothills of the Rockies which is what we are is a harsh climate for fruit trees.

[hoosierbanana]

I should have actually said freeze instead of frost, we had a bunch of near freezing temperatures in October before but no frost in that spot so they were still leafed out and then it went down to around 25, which was enough to kill growing tips and blister the bark around the lenticels of green growth. Then the ones that were covered for season extension were uncovered a week after that and saw a couple 29-30 nights so they would drop their leaves. Then they were all tucked in before the Thanksgiving freeze down to 15.

When I started growing figs I found a bunch of aged trees a half zone up in Wilmington, one was about 25’ wide. The vortex winters got that one, probably most of the others as well. It has been tough most winters since, and the extra 2 feet of rain last year had them growing like weeds.

It seems like they ripen faster under the row cover than the extra warmth can account for, I was thinking it could be ethylene building up, what do you think Steve? I tried a Google search but because it is made of polyethylene I’m getting all sorts of random results.

[fruitnut]

@hoosierbanana

It seems like they ripen faster under the row cover than the extra warmth can account for, I was thinking it could be ethylene building up, what do you think Steve? I tried a Google search but because it is made of polyethylene I’m getting all sorts of random results.

I’d say it’s because it’s warmer. In those pictures your plants look really advanced compared to here. But then I had so much freeze damage it’s hard to tell. Even compared to my greenhouse figs yours look behind but not that far.

[hoosierbanana]

It has been an unusually warm spring so far and things are way ahead, though the ones under the row cover are farthest and it seems like Adriatic JH leafs out early.

They don’t ripen this fast in a ventilated greenhouse that is warmer… so it I did a little reading and found there are indicator plants for ethylene so I might test it this fall. Seems like ethylene does trigger figs to ripen faster though and they produce it during the ripening process. https://www.ncbi.nlm.nih.gov/pubmed/16657774

I imagine it would depend on lots of factors, wind being a big one.

[Rosdonald]

Can you list some varieties that did well as a few of those that didn’t make it? Was their cold tolerance true to the hardiness listed for those trees? Figs are new to me, and I’m concerned that several of mine need to be dug up to make it. I have Chicago hardy, Celeste, brown fig, others. Do you recommend wrapping, mulching, bringing inside?

[hoosierbanana]

Hardy Chicago types like MBVS, Gino’s, Black Greek, and Takoma Violet have been the best overall for me here in 7a. They usually do die back during winter if not protected but still set well that year and ripen a small crop.

I also posted a thread last year observing fruit set on different varieties. Inground Fig Set Observations and Discussion (Pic Heavy)
Overall, the best performers were the Hardy Chicago types, Florea, Easton Purple (LSU Tiger), Longue d’Aout and Adriatic JH. And for split and bug resistance, the Hardy Chicago types usually win hands down.

I did have Celeste in the ground for several years and it set very few figs early enough to ripen after dying back significantly. In my experience all varieties will die back if not protected when they grow late into the season, and the soil here is very rich so even without any water or fertilizer a tree that is young, had winter damaged or was pruned heavily will grow almost up until frost.

People think of fig hardiness in terms of absolute winter lows, but that is a misunderstanding, they can be killed back by relatively mild freezes in the 20s if not well hardened. The only thing that I’ve found controls growth is an established branch structure developed by 2-3 years of protection. People also say that keeping a tree in a container for several years will improve hardiness, but what happens for me is they want to grow like mad a year or 2 after planting and lost that hardiness.

I don’t wrap in the traditional sense, I know it usually works (I also know an old timer who wraps had all of his trees die back during the polar vortex years) but requires a lots of time and materials and I have hundreds of figs to protect. The best and quickest ways for me are to bend young flexible trees nearly flat to the ground and cover with soil, bags of leaves or mulch and older trees get bent over to 3-4 ft. using anchored lines and covered as a row with 2 or more layers of agribon row cover. Those ways are much quicker, so I can have them covered before sudden cold snaps that do damage.

Judging variety hardiness is tricky because of growth rate, but it seems like the Hardy Chicago types, Florea, and Easton Purple perform the best (but still need protection for their first 2-3 years). Adriatic JH and LdA appear to have died back to the main trunks or more this winter unprotected, they are both very strong growers and would have taken quite a while to protect since they got so big.

Growing in containers has worked OK for me, but the crop is so much less because of relative tree size, and I need to load them all into a truck so I am phasing them out because that is a lot of work, the type of irrigation system needed is high maintenance as well. I have been experimenting with compost socks the past few years which I tip over and cover in their growing space to reduce the work, and just use drip tape which is a lot easier to setup and maintain.
Growing fig trees in compost socks. When grown in containers you can get away with more varieties, though fruit set and ripening time can still make things difficult. I think I would dig the Celeste and keep it in a container, early spring is the best time to do it and after a few years of dying back the root crowns become too wide to fit into a container so you should not wait too long. I dug out the one I had in ground but kept a small tree that came to me mislabeled as something else.

I got rid of lots of varieties just because they seemed to be synonyms (there are tons in circulation), choosing the healthiest ones to keep and propagate from. Lot’s of others just never did well and were discarded. Here’s a few I trialed for a while in containers but got rid of and why, off the top of my head.

Verdal Longue- too late ripening, poor fruit set.
Maltese Falcon- Mission type, poor fruit set, unremarkable fruit.
Black Madeira- too late ripening, not sweet enough.
Col de Dame Blanc/Gris- too late ripening.
Panache- too late ripening.
Marseilles White/Lattarula- poor fruit set, bland.
Kadota- splits, unremarkable.

I’m thinking of digging out or grafting over several inground trees this year as well- Noire de Barbentane, Atreano, Sultane, Improved Celeste, and an unknown Brunswick type.

[Rosdonald]

Thanks for all the information! It is most helpful, and will guide me going forward. I overwintered my hardy Chicago, and covered it with leaves and mulch (it was a young plant) It seems to have died back to the ground and is showing some but minimal signs of growth. I understand better about the importance of hardening off in addition to temperature swings.

[hoosierbanana]

The row cover was really a game changer, in addition to protecting them from cold snaps it can also give you a few extra weeks of harvest in the fall.

[zendog]

@hoosierbanana, why are you thinking of getting rid of improved Celeste? Just curious since I just started some cuttings in hopes of replacing my regular Celeste that is in a container and often drops a lot of figs.

[hoosierbanana]

My inground tree doesn’t set well, other people have reported theirs are productive, but the flavor is not as good as regular Celeste to me and it has had some difficulty ripening. I am keeping the ones I have in compost socks for now though.

[hoosierbanana]

Update for this year. Uncovered trees today, much later than usual because of the cold spring. The Adriatic JHs were not covered because they had gotten too big, I hoped they would only die back to the main trunks, especially with the mild winter, but they look dead to near the ground.

The MBVSs that survived 3 previous winters were split into 3 groups this year, 5 were covered before the first freeze of the year (~25), 5 were covered after, and 7 were not covered. When checking on them through the winter it seemed like teh ones covered before the freeze would do the best, but it looks like the ones covered after are farthest ahead. The did have an extra layer of agribon. Damage on the ones left uncovered is not bad, some growths almost alive to the tips but just breaking bud now. Observing the damage, it is really hard to judge any sort of varietal hardiness because there is so much variation within the same variety.

Also covered one full row each of MBVS and Gino that had died back the previous winter. One row is ahead of the other, but deer busted into the cover less on that one to eat the dormant buds so it is not surprising.

Also did a short row of RdB, they are looking fine.

Of the ones that were not covered there was almost total die back, but a few trees had a couple growths that survived almost intact, which seems odd. They were MBVS and Easton Purple (LSU Tiger). EP seems to have good cold hardiness, 2 trees out of 10 had a growth or 2 survive while only 2 MBVS out of ~40 performed the same.

Weirdest fig survival was some seedlings in containers that I left out to freeze because they still haven’t made any figs, they made it totally fine. I think it is probably a hormonal thing rather than a longterm trait, but they bought themselves another year in any case.

[DCinFLX]

Do you think the advanced state of the covered MBVSs is explained more by the heat boost of row cover in the spring sun, or from taking less damage over the winter?

I’ve noticed that regardless of age or planting date my trees take heavy damage over the first winter then do very well surviving their second winter. That leads me to think–

1. No benefit to planting older trees.
2. For the 1st winter, protection should either be comprehensive, or minimal (mine was in between, lowest temp was 10F).

[hoosierbanana]

It has to be the warmth. The 2 rows don’t actually have much of a difference in damage, just more cool air getting into the row the deer busted holes in.

I agree about planting young trees, I either bend them flat and cover completely the first winter or just let them freeze back. It does not seem to matter much as long as they have buds below the soil line to regrow the next year. Older trees can be hardier if they have an established branch structure that limits growth, but sooner or later they are going to have a growth spurt that makes them vulnerable.

[DCinFLX]

I uncovered a row yesterday, and while they aren’t anywhere near as advanced as yours, I was very pleased by the results. The coldest temperature these trees saw was 10F, though I’m starting to think my temperature probes read a couple degrees colder than actual.

This is unknown Mark Nelson’s (I was told a Celeste variant but I didn’t think those held onto their brebas…), and Chicago Hardy.

!

Here’s an Adriatic JH, all the wood shown is viable. This was planted last year just before Memorial day, so that pokes holes in my “all trees take damage in their first winter regardless of age” hypothesis, but that’s OK with me. It was strange needing to prune after winter to shape the trees.

Next up is breaking down the hoops, weedwhacking, and putting down landscape fabric so it isn’t such a jungle. I’d rather throw down some no 2 stone but this isn’t my land so I need to keep it reasonably easy to break down.

[PharmerDrewee]

All of my trees were covered with tarps here in SE PA. Most had minimal damage except perhaps the tips and I even got some breba.

I visited a gentleman who does not cover his trees in NJ and there was no damage along with a breba crop forming. Among them were Malta Black, I-258, Col de Dame Grise, Takoma Violet, Dalmatie, Adriatic JH, Nero 600M, and Ronde de Bordeaux. I didn’t want to ask to take pictures although all the trees were impressive.