[GraniteStater]

Originally Posted by ben young

I live in Pittsburg NH at 2200 feet. I gave up on fruit bearing trees years ago.I get +5 feet on the ground of snow,last winter we got +230 inches. The snow seemed to help the roots of my trees ,however they never could recover from a summer of mid June to mid August.I now start tomato's in my greenhouse and move the pots outside mid June and then tent them all summer..A big deal if they get pink. .We eat lots of fried green tomatoes .lol

Have you seen lows in the 20’s this month so far?

[arctichomesteader]

Originally Posted by GeoffD

Two months later but...

How do you avoid winter kill with zone 5 fruit trees in northern Vermont? You see -30F overnight temps in January many years, right? Does it get enough sun that you don’t have a deep frost line?

A variety of factors work into that. First off some zone 5 trees are more cold hardy than other zone 5 trees but that requires trial and error to sort out. The big factor for me is a microclimate. My land is on a southern slope of a mountain. Roughly 1700 feet elevation at my orchard. The mountain's peak is about 500 or so feet above that point. The land forms a shelf in shape where my orchard is. A near vertical rise of about 6 feet from the level of my orchard's northern edge to the level of the ground above that (a natural shape which was improved somewhat and taken advantage of for a logging road built there decades ago which is now almost unusable) forms a shelf which provides a natural wind break and lots of thermal mass. The southern slope gets the sun's warmth, the topography gives me thermal mass that moderates the temperatures. The ridge above me cuts down on the intensity of north winds. I'm high enough to have the cold air sink below me instead of settling as it does in the valley below me, but low enough not to be too exposed to the wind. The site of my orchard is routinely 5 to 10 degrees warmer than the surrounding area, which is a big difference when the surrounding area hits those -30 temps as -25 can be tolerated by more trees than -30 (the difference between zone 4 and 5 really). I also get more snow than the valley and deep snow acts as an insulation. When it's real cold and snow is scarce I will add some to the base of the trees.

The southern slope causes some problems too. Southwest slope injury is a common name for when the sun warms a tree up by the afternoon, then the deep freeze of the night freezes it, causing serious injury. I paint my tree stems white up to the branches. This helps by blocking some of that heat. Warmth is helpful in what I'm doing but you want trees to remain dormant all winter. Snow pack helps with that battle. My most sensitive trees are in front of my cabin on the north side of it. They get enough sun during the summer, but the low angle of the sun in winter means they get hit by the sun less and therefore don't get prematurely warmed out of dormancy. The snow and ice keeps them dormant later on the north side of the cabin than if they were on the south side.

I may experiment in the future with wrapping some of the trees, particularly peaches and sweet cherries. The trees survive and grow well but there is winter kill of some twigs and buds on some of them. A barrier to the wind may help there.

In the Middle Ages in Europe they built extensive fruit walls to grow fruits well north of where they would have otherwise, relying on thermal mass much as my hillside provides. https://www.lowtechmagazine.com/2015...n-farming.html

I'm experimenting with this idea a bit too. I have a low stone wall backfilled with soil (flowers in that bed) I'm growing some grapes against that are out of their zone at my place. I also planted a pecan tree against an old stone wall at the upper end of my orchard. Time will tell if it will survive and thrive.

100 feet below my orchard and cabin and the same trees that thrive where I planted them would die in a single winter. It took a few years and some studying it to figure out what I have.

[ben young]

Originally Posted by GraniteStater

Have you seen lows in the 20’s this month so far?

I live at 2200 feet.We dont get the early frost like the upper Connecticut River Valley.My lows have been in the low 30s " w e get a steady wind. of 10mph..The 2ed and 3ed Conn.river area have been in the low to mid 20s this month.
We get more snow and our daytime temps are lower than the valley.

[arctichomesteader]

Originally Posted by ben young

I live in Pittsburg NH at 2200 feet. I gave up on fruit bearing trees years ago.I get +5 feet on the ground of snow,last winter we got +230 inches. The snow seemed to help the roots of my trees ,however they never could recover from a summer of mid June to mid August.I now start tomato's in my greenhouse and move the pots outside mid June and then tent them all summer..A big deal if they get pink. .We eat lots of fried green tomatoes .lol

There are apples, maybe some pears, and some plums that will grow there. Probably a zone 3 if I'm not mistaken. People are growing apples in Alaska, after all. There are some nurseries that specialize in fruit trees for far northern areas.

[ben young]

Thankyou for that Imfo. however I am about done with the frustration of fruit trees.. You and I are semi close in elevation and latitude .Last year we had a dozen or more days the high was in the mid teens or more below zero. This was not when the Upper Great Plains had their cold wave.
On a side note the Tall Timbers on Back Lake in Pittsburg has twice in the past forty years have hit an unofficial negative Sixty , with a very good thermometer ,but they are not an official station.