Will a micro-climate really work?

R Steele mentioned something in my thread about paw paw seeds that brought up an issue I've been curious about for a while now.  The theory is that you can create a micro-climate that will allow you to grow trees in a colder zone than usual.  I understand using micro-climates to a small degree, like using a more north facing slope to keep your fruit trees from blossoming too early and losing the flowers to a late spring freeze.  I'm struggling to understand how they can be used for something like growing a zone 5 or 6 tree in say, zone 4.  Suppose I use that advice I have seen given, and I plant a tree, make a cup shaped pile of stones behind it to the north, and put a small pond in front of it to help reflect more sun onto the rocks.  The sun and the reflected sun heat the rocks and keep my tree warmer.  I can understand that.  I can understand how this keeps my tree warmer at night, and may extend the season somewhat.  Fast forward to January.  Now it's -25 degrees at night, the sun doesn't come up until 7:00 in the morning and sets at 4:30, and most days it's cloudy out.  I can't believe I'm still gaining anything from the pile of rocks (now covered in snow) or the pond (frozen solid and covered in snow), so I don't understand how I really gained anything.  The tree may have stayed warmer an extra month or so.  Is that really enough to keep it alive through the winter?  Additionally, once the water is frozen and the rocks get down to -25 or -30 degrees, aren't they going to hold onto that cold, just as they did the heat, and keep the tree colder for longer than it would have been?

There is a book that has some ideas for upping your zone, I think it's called Push the Zone. It works, sort of, unless you go greenhouse crazy. I would say the 10 year winter will likely get you. I'm growing olives on a south-facing wall, and they made it through a regular winter. So far the pomegranates are happy. My protected figs are producing breba figs, the unprotected one's died to the ground. I have honeyberries in a frost pocket, and they are thriving. That being said I have had no luck with guava, they grow in misery but don't do much, and so far I hae killed a bunch of "hardy" citrus. I have a very long list of things I have killed though.

I would say it works, but I built the plants around the earthworks and buildings, not the other way around. And don't expect everything that glitters to be gold, often there is a pollinator issue or fruiting time issue. Ask me how my loquats are doing...

I have similar experiences to Tj. I guess my advice would be to go whole hog on really reliable perennials only for a while and then introduce some "reach" and experimental stuff. What's your orchard like so far?

For example, pomegranate is a reach here. But I meet people with no or just a few surefire trees who are going gung ho on pomegranate and citrus. Things like apple trees, pears, plums, and even some peaches would be a much better first choice, as well as unusual but regionally bulletproof plants like quince, medlar, some American persimmon, etc

I'm still working on developing my microclimates.  I have the same concerns about how much good a sun trap can do in the dead of a WI winter.  But I do think wind protection can get you a half a zone or more.  And the heat bleeding off a heated building could give another half a zone.

I know a lady who has a protected food forest (sun trap and wind protection) who is growing butterfly bush in zone 4a (not near a building or wall).  

My hunch is that the only way to get serious zone pushing up here is to use snow.  Maybe dig a suntrap down a couple feet and plant living snow fence plants all around.  Then you just have to hope for enough snow to get caught in the depression to cover the desired short plant before it gets too frigid.  Maybe quince would be a good candidate?

Another option would be to identify warmer zone plants (say zone 5) that only can't make fruit in zone 4 due to the length of the season.  Then a sun trap or warm microclimate that heats up a week or two earlier and stays warm a week or two longer in the fall can make a difference.

I think you have to look at worst case then weigh that with common sense.

In my area we get several little freezes that only last the night. I can work around that with, say, a citrus tree. The problem is every 3 to 4 years it may get down to 17 degrees and stay there for 3 days. I can't work around that.

I have two peach trees and a nectarine that seem to get frost damage most years. Next door the peaches always produce. So I’m wondering how to tweak spring. The micro-climate can be complex. Every plant, every climate, every location is unique. I “think” my issue is wind, rather than sun. The neighbors peaches are in the shade. I think Permaculture is much more difficult than most people think. Or maybe I’m just not that bright!

Could it be that the shade is keeping snow on the ground longer and delaying flowering for their peaches compared to yours?  

James Landreth wrote:What's your orchard like so far?

Edibles I have so far are apples, both planted by me and old ones that were likely planted by wildlife, cherry trees, a plum tree, hazelnuts, walnuts, autumn olive, seaberry, siberian pea shrub, service berry, gooseberry, jostaberry, raspberries and wild blackberries, artic kiwi, several kinds of mints, lots of alliums, comfrey everywhere, joe pie weed, catnip, and lots of various herbs and things that I have probably forgotten.  Many other things that I have planted for wildlife that aren't really edible by me.  Lots of natives like hackberry and nine bark.  I also have some Dawn Redwoods I'm growing just because they are beautiful and were thought to be extinct.  American persimmons are on the list for this spring, as well as more nut trees.  

Paw paws interest me very much and are one of the reasons for this post.  Goumi is another.  I'm really only trying to gain a zone or so.  I don't have any thoughts of trying to grow bananas or the like here, I just want to be able to grow some things that are just past the edge of what I can grow.

wayne fajkus wrote:I think you have to look at worst case then weigh that with common sense.

In my area we get several little freezes that only last the night. I can work around that with, say, a citrus tree. The problem is every 3 to 4 years it may get down to 17 degrees and stay there for 3 days. I can't work around that.

It gets -25 F here every year, sometimes for weeks in a row, with rare dips to -40 F.  That's what I'm trying to work around :)

Hi Trace,

The types of microclimate I was refering to, are as someone else mentioned unnatural ones, like the radiant heat from a heated building, coupled with maybe some solar reflection from the building and wind protection from the building. With all those factors in play, a few strings of Christmas lights and a frost blanket could make the difference during those hard winters, especially if your tree is very healthy allowing for maximum sugar storage within the tree.

However as others mentioned the 10 year winters, which are caused by 10 to 11 year solar minimum cycles are the main issue. And since these solar cycles naturally fluctuate giving greater solar influence over the effects of the solar minimums, which culmiates also in approximately 200 year solar minimum cycles, and many other distributions of deepening cycles which climax on whats referd to as Grand Solar Minimum. Which explains the reason I suggested going with more hardy berries or fruits, rather then use micro climates. As we are approaching Grand Solar Minimum which is the climax of all 10 year winters, which will increase the harshness of the 10 year winters over the next 40 years. In other words we haven’t seen anything yet, regarding the harshness of 10 year winters.

Even climate scientists say this Grand Solar Minimum cycle, should have put us into another ice age. Hence my suggestion to not push the boundaries of climate zone hardiness, but rather focus on more hardy things, that will be long lasting as we approach Grand Solar Minimum.

Just a suggestion, hope it helps.

Trace Oswald wrote:

James Landreth wrote:What's your orchard like so far?

Edibles I have so far are apples, both planted by me and old ones that were likely planted by wildlife, cherry trees, a plum tree, hazelnuts, walnuts, autumn olive, seaberry, siberian pea shrub, service berry, gooseberry, jostaberry, raspberries and wild blackberries, artic kiwi, several kinds of mints, lots of alliums, comfrey everywhere, joe pie weed, catnip, and lots of various herbs and things that I have probably forgotten.  Many other things that I have planted for wildlife that aren't really edible by me.  Lots of natives like hackberry and nine bark.  I also have some Dawn Redwoods I'm growing just because they are beautiful and were thought to be extinct.  American persimmons are on the list for this spring, as well as more nut trees.  

Paw paws interest me very much and are one of the reasons for this post.  Goumi is another.  I'm really only trying to gain a zone or so.  I don't have any thoughts of trying to grow bananas or the like here, I just want to be able to grow some things that are just past the edge of what I can grow.

That's a great start!! I often see goumi rated to zone 4, and some types of autumn olive, thought I don't know how true that is. You've probably heard of them, but in case you haven't, have you heard of St. Lawrence Nursery in upstate NY? They're in like zone 3 or something (I think it occasionally hits -50). They have an apricot that can survive that and reportedly fruit in a 60 day growing season! You might check them out. They don't have goumi but it sounds like they experiment with things over time.

There's also Northrop mulberry, which is reportedly hardy (probably upon establishment) to -50

R. Steele wrote:Hi Trace,

The types of microclimate I was refering to, are as someone else mentioned unnatural ones, like the radiant heat from a heated building, coupled with maybe some solar reflection from the building and wind protection from the building. With all those factors in play, a few strings of Christmas lights and a frost blanket could make the difference during those hard winters, especially if your tree is very healthy allowing for maximum sugar storage within the tree.

However as others mentioned the 10 year winters, which are caused by 10 to 11 year solar minimum cycles are the main issue. And since these solar cycles naturally fluctuate giving greater solar influence over the effects of the solar minimums, which culmiates also in approximately 200 year solar minimum cycles, and many other distributions of deepening cycles which climax on whats referd to as Grand Solar Minimum. Which explains the reason I suggested going with more hardy berries or fruits, rather then use micro climates. As we are approaching Grand Solar Minimum which is the climax of all 10 year winters, which will increase the harshness of the 10 year winters over the next 40 years. In other words we haven’t seen anything yet, regarding the harshness of 10 year winters.

Even climate scientists say this Grand Solar Minimum cycle, should have put us into another ice age. Hence my suggestion to not push the boundaries of climate zone hardiness, but rather focus on more hardy things, that will be long lasting as we approach Grand Solar Minimum.

Just a suggestion, hope it helps.

Understood.  I try to plant things that are good to zone 3 at least, "just in case".  At some point though, I want to explore some other options.

James Landreth wrote:

Trace Oswald wrote:

James Landreth wrote:What's your orchard like so far?

Edibles I have so far are apples, both planted by me and old ones that were likely planted by wildlife, cherry trees, a plum tree, hazelnuts, walnuts, autumn olive, seaberry, siberian pea shrub, service berry, gooseberry, jostaberry, raspberries and wild blackberries, artic kiwi, several kinds of mints, lots of alliums, comfrey everywhere, joe pie weed, catnip, and lots of various herbs and things that I have probably forgotten.  Many other things that I have planted for wildlife that aren't really edible by me.  Lots of natives like hackberry and nine bark.  I also have some Dawn Redwoods I'm growing just because they are beautiful and were thought to be extinct.  American persimmons are on the list for this spring, as well as more nut trees.  

Paw paws interest me very much and are one of the reasons for this post.  Goumi is another.  I'm really only trying to gain a zone or so.  I don't have any thoughts of trying to grow bananas or the like here, I just want to be able to grow some things that are just past the edge of what I can grow.

That's a great start!! I often see goumi rated to zone 4, and some types of autumn olive, thought I don't know how true that is. You've probably heard of them, but in case you haven't, have you heard of St. Lawrence Nursery in upstate NY? They're in like zone 3 or something (I think it occasionally hits -50). They have an apricot that can survive that and reportedly fruit in a 60 day growing season! You might check them out. They don't have goumi but it sounds like they experiment with things over time.

There's also Northrop mulberry, which is reportedly hardy (probably upon establishment) to -50

Autumn Olive does great here.  I have quite a few cultivated varieties as well as the wild ones.  I have seen goumi rated at zone 4, but far more often zone 5, so I'm going to give it a shot and see how it goes.  Mulberry also grows well here.  I forgot to mention those because I've never planted them, but the birds have planted lots for me :)

Thanks for the tip on that nursery, I'll give it a look.

I have a patch of asparagus on a west wall. It produces a good 2 weeks before my other 2 patches. The brick wall warms it sooner in the year.

This is what i see in terms of micro climates. Finding those areas that kickstart things sooner. Or areas that keep things producing later. Once you discover one of these accidental microclimates,  its easily duplicated.

Trace,

If you don't already have them, try honeyberries, also known as haskap berries. They have many new and productive named honeyberry varieties to choose from, all zone 3 if I recall correctly. Also rubis is another cold hardy berry, thats also like a ground cover. I belive it grows native in the artic regions. The Rubis berry looks like a salmonberry, though I can't speak on the flavor as I've never personally tasted Rubis. Rubis isn't highly productive at producing berries compared to commercially propagated berry species, but it's extremely cold hardy if I recall correctly.

Food for thought.

R. Steele wrote:Trace,

If you don't already have them, try honeyberries, also known as haskap berries. They have many new and productive named honeyberry varieties to choose from, all zone 3 if I recall correctly. Also rubis is another cold hardy berry, thats also like a ground cover. I belive it grows native in the artic regions. The Rubis berry looks like a salmonberry, though I can't speak on the flavor as I've never personally tasted Rubis. Rubis isn't highly productive at producing berries compared to commercially propagated berry species, but it's extremely cold hardy if I recall correctly.

Food for thought.

I do have honeyberry bushes. I believe I have 4 varieties but only two are producing so far.  Im going to take cuttings of those this year and try to get at least twenty bushes going.  I hadn't heard of rubis, I'll look into it,  thanks.

I just ordered three bush cherries today.  They are from the "romance" series.  They are supposed to be very hardy,  so I'm looking forward to trying them.

I'm a 4b with a favorite apple tree rated for zone 5 or warmer. I wrote to an apple website about the possible consequences of zone pushing on this scale for apple trees and this was their reply:

That should still work, but you might find that the tree struggled in a bad winter. However by planting it in a sheltered location and perhaps taking steps to protect it from extreme cold the tree would probably be fine.

So I'm guessing in a really really bad winter, there's going to be some damage unless I can move the tree indoors (fairy godmother, where are you?) but I can take steps to minimize the worst of it, and most winters probably wouldn't hurt it much. I wouldn't expect to get top productivity, but I'm okay with that as long as the tree is healthy and produces something most years.

Here's an example of man-made microclimates that work:
Canary Island vineyard

The more macro your micro climate, the better it will work. It’s a matter of thermal mass to surface area ratio and exposure to heat loss to the atmosphere. If you are in the middle of an open plain with no windbreaks, you are correct that a small pond and rock pile will do little in mid winter once it’s stored heat is mostly spent. However, if those same features were surrounded by established evergreens except for an opening for the sun path, they would lose their heat much more gradually. The forest floor in old growth conifers of the nw is on average 20f warmer on winter nights and 20f cooler on summer days, and 30% more humid. Microclimates do in fact occur and are easily observable, just go to any west coast (of North America) mountain range, or the Bay Area, and look at the vegetation. However, we can’t expect to small features vast open spaces to have an outsized effect. One might say that it takes a long time to reestablish conifer forests, and I would say that is part of why it’s called permaculture.

I saw the book 'Push the Zone' mentioned here. If that small book by David the Good is meant (which indeed has that title), I don't think that is of any help in your case. It's a funny book, but it isn't about growing trees in zone 4 which are normally growing in zone 5 or 6. It's about growing tropical plants in Northern Florida climate. Only some of the tips given in it can be of some use in colder climates.

Ben Zumeta wrote:The more macro your micro climate, the better it will work. It’s a matter of thermal mass to surface area ratio and exposure to heat loss to the atmosphere. If you are in the middle of an open plain with no windbreaks, you are correct that a small pond and rock pile will do little in mid winter once it’s stored heat is mostly spent. However, if those same features were surrounded by established evergreens except for an opening for the sun path, they would lose their heat much more gradually. The forest floor in old growth conifers of the nw is on average 20f warmer on winter nights and 20f cooler on summer days, and 30% more humid. Microclimates do in fact occur and are easily observable, just go to any west coast (of North America) mountain range, or the Bay Area, and look at the vegetation. However, we can’t expect to small features vast open spaces to have an outsized effect. One might say that it takes a long time to reestablish conifer forests, and I would say that is part of why it’s called permaculture.

Micro-climates absolutely exist.  I'm really trying to determine if there is reasonable way to create a micro-climate that will make any actual difference here.  My food forest area is surrounded by large trees, and is on a hill that is surrounded by much larger ridge lines on all sides.  Picture a large mixing bowl with a small bowl inside it, bottom side up.  On that inner bowl is my food forest area.  It is well protected on all sides from most wind.  My current thinking is that a rock pile of basically any size I could create, can't possibly hold heat through a WI winter.  Very large lakes here freeze many feet deep in the winter, so making a lake large enough to make a difference seems impossible as well.