They are small (on Kyrmsk 1 root) but well formed so far and are showing a good number of flower buds.

I would never let a apple or plum fruit at this age/size, but I understand it is common to let peach.

What would be a reasonable crop load to allow on a tree this young? Lets try to put this in terms of a fruit per length of branch or some such ratio.

Part of me says go ahead and be greedy. Peaches are so iffy for us here that I am sure I could lose the whole tree anytime (might still this winter). But I like to hopeful and really don't want out runt out the trees.

I would think a more vigorous tree would be less likely to die from winter cold but as far as your question goes, let the tree be your guide. See how much vigor it shows in May-early June and thin accordingly. No one can offer specific guidance without knowing how it comes out of dormancy. The most you'd want is a peach every 7" of branch or so.

My peaches in the ground are all seedlings and they grow like weeds.

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Normally I have no interest in dwarfing rootstocks. We have plenty of space and I like trees not bushes! But I came across some data out of Cornell. I guess when they were running a trial of the K-1 they got hit with some brutal winters (for them) and they noticed that the trees on k-1 consistently suffered much less damage than all the other rootstocks. They speculated that they were shutting down and hardening off earlier. But it wasn't what they were screening for, just by-product results. Also the k-1 is supposed to tolerate colder wetter soils and that can definetly be us at times.

So when I noticed a nursery I was getting some other stuff from had the PF 24CH on the K-1, I thought I would give it a try.

http://www.nyshs.org/pdf/fq/2005-Volume-13/Vol-13-No-4/Peach-Rootstock-Trials-at-Geneva-A-Progress-Report.pdf

I may have inferred the cause of earlier shut down (I see no mention in the abstract) from the experiences of a NAFEX grower in MN. I can't recall the fellows name but I think Frank has posted a link to his writings here on GW. He has been experimenting heavily with growing peaches in z4. As I recall his best results were with p. americana rootstock and he linked it to earlier shut down. He also noted severe overgrowth problems but figured the trees would be so short lived this far north that it was not an issue.
Anyhow, I might have assumed the K-1 worked through he same mechanism since it is essentially a plum. But I am pretty sure I read it somewhere along the way as well.

I chased out the info a lot last winter. The multi-state trial that Cornell was participating in had mixed results out west. In California they noted graft incompatibility with several cultivars and K-1. and if I recall in Utah the relative yield was not so great, but fruit size good.

Here are a few other links making note of some other k-1 trials with peach:

http://njaes.rutgers.edu/peach/orchard/New_and_Emerging_Rootstocks.pdf

http://www.michiganpeach.org/peacharticles/newsletters/mps.issue1.table.2005.pdf

Someday I will learn to keep a horticultural file on the computer so I can refer back more quickly and precisely, as I am sure I found a bit more detail before.

Rob, the guy's name is Dave Griffin. He posted here on GardenWeb a while back. Lately, he seems to be more focused on trying to develop small peach trees that are more easily covered for winter protection. That might be something that would work with your trees on Krymsk 1.

I've no experience with dwarfing peach rootstocks. On standard rootstocks Lovell, Bailey, and Halford peaches have plenty of vigor here.

When mulched with grass clippings (which I don't do anymore) the constant source of N through the growing season would produce high growth rates. Some trees grew from a 3/4" to 3" in diameter by the end of the second season.

When mulched only with wood chips, we get about 4-5' of new growth on a new tree.

My gut feeling is with a significantly dwarfing peach rootstock, it may need a higher level of fertility and water management to maintain a reasonable degree of vigor.

I noticed Cornell had their peaches in what looked like raised terraces. I'm sure they also irrigate and fertilize, which may be key to managing some of these rootstocks.

I've had quite a few peach, nectarine, plum, and pluot on K1 for about 5 years. Both in-ground and potted, greenhouse and outdoors. Some of my best fruit last year, 24-30 brix, was off K1 trees. One reason the fruit was higher brix is that the trees were more drought stressed, in general, than Citation. I run a water deficit to increase brix so drought was intentional.

The K1 seems compatible with plum and pluot but there have been serious overgrowth of some peach scions.

I think the trees can runt out especially with droughty conditions. That might be good if you appreciate something special in sweetness and flavor. But it could be a loss if the stress goes too far or the tree quits growing.

I'm not planting more. I can do all I need with Citation.

These are a definite experiment. I like a challenge, and peaches are my wife's favorites...she has put up with a lot of money and time going into my/our plantings so I thought we would give them a shot. In retrospect I wish I had put in something on a standard rootstock just to have the comparison.

I have heard of folks building little foam sheds for the trees....not really the direction I want to go, although it would be easy to keep the trees to that size at this point.

If we got anywhere near the consistent snow cover we used to receive I would gladly bury them up 3-5'...but I am looking at 2" right now and we have not had more than 6" all winter....

Training them extremely low and covering with tarp/straw might be a viable option. I think starting with your own seedlings would be the way to go, certainly the trees I received were already too high for that. I suppose I could have planted them at a severe angle into the slope. Our vole populations have been brutal the past 3 years, and although hey seem on the decline I think a set up like that would end up with a well eaten tree for us.

The dwarfing with K-1 is reported to be all over the place dependent on cultivar, from 30-80% of standard. Having almost no experience with dwarfing rootstocks I just don't know what to expect.

They put on about 12-20" of shoot growth this past year, which seemed to me acceptable for trees that just got planted. I tend to be pretty gentle with the N on year one...probably too conservative. At planting time the risk of burn/shock worries me, and with our short growing season and hard winters I don't like to push growth later in the summer when they have begun to establish and the burn is less of a concern.

I look at them now and have a hard time imagining them supporting much fruit..But that may just be because I am used to standard trees, these guys look like well formed babies to me. If they really take off in spring perhaps I will try to get a small crop (seems a shame to "waste" this mild winter) But my gut tells me I shouldn't allow more then a few token fruits to present to my lady.

I believe that you would not need to fill the area in with leaves if you covered it with an insulated horticultural blanket of the type perennial nurseries use.

A whip usually has live buds right to the graft union so you could train it as low as you want.

Hman,

I don't think there is much advantage to dwarf rootstocks with peaches (other than the possible cold hardiness that Rob mentions). Since peaches are already precocious on standard rootstocks, dwarfs offer no advantage there.

That said, I've never tried to keep a peach tree at a 1' height. I'm sure it can be done w/ a standard rootstock, but it's got to involve a tremendous amount of pruning. Even keeping trees at 8' requires me to really stay on top of pruning. I wonder if there might be some special issues keeping a standard tree at 1' (i.e. would that much pruning keep more wood in a perpetual juvenile state causing very low production?) I don't know.

Some of these issues were discussed in a thread with Dave Griffin last year (see link below). Interestingly, he indicated in his experience, dwarf rootstocks were less cold hardy than standards. His answer was to try to use genetic dwarfs to help keep the peach trees small.

I sure wish Dave had mentioned more rootstocks by name, certainly his comments are not encouraging in regards cold hardiness. The water management details were helpful to consider. We don't have a lot of control over water. Certainly I can apply it when needed but for the most part we get pretty steady rain spring summer and fall. Not much way to reliably restrict water without a green house like Fruitnut.

Returning to training,I thought I remember a discussion a while back about the difficulty in getting peaches to push new limbs low even when quite young? Or was that a few years out from planting?

Fruitnut, we are growing in such radically different climates,. But just to have a number...what sort of growth were you seeing on your k-1 peaches in their early years? I assume you were not water stressing them until bearing? And did you notice strong differences among cultivars?

When young the peaches on K1 seem to grow about as much as on any other root. On all the amount of growth is a factor of growing conditions. Push them and they grow fine. In pots they get about the same size as anything else. In-ground they have been about half the size as on Citation.

The difference between Citation and K1 is the in-ground K1 trees became so water stressed they needed to be cut back to get top growth back in balance with the roots. We'll see how they do this year after cutting back the top. If they are overly stressed this year I'll probably remove them.

As you say our conditions are so different I don't know that what I'm seeing tells you anything. I know I'd not plant them outside here again. My outside trees are overly water deficit under all but heavy watering. I don't know where people back East stand on water deficit. No one wants to test brix and I don't know another measuring stick. For all I know peaches back East could be routinely in a good range of water deficit for high brix.

I don't think I am familiar with the type of insulated nursery blanket you described. Can you point me toward a source/info?

Rob,

My experience has been normal buds form on new peach growth only. Adventitious buds will sometimes later form on more horizontal growth (like scaffolds). However, on vertical growth (like the trunk) I've had practically no luck getting adventitious buds to form. I've not tried anything radical like cutting the whole top of the trunk off (thereby trying to force the trunk to form adventitious buds) but I know of one commercial grower who's tried that and he said it simply kills the tree.

Because peaches won't grow new wood on the trunk, I've always had to pick my scaffolds the first season, and at times the pickings have been slim. I like to start my scaffolds low but there are times no live buds exist on the lower portion of the trunk. I also like to keep at least two inches (vertically) between scaffolds and keep them evenly spaced around the tree, with good crotch angles, and a diameter no bigger than 1/3 the diameter of the trunk.

Trying to find the scaffolds that meet all that criteria can be difficult if there isn't much down low. I've been known to try to find at least one live bud down low, cut the tree off right above that bud and grow a new trunk to get some good scaffolds. I've also had some luck notching above a dormant/sleepy bud to get it to sprout.

But as I say the problem is sometimes finding any live buds at all down low. I have a couple trees out there with only two scaffolds (those were the only buds/shoots low enough to choose as scaffolds at the time of planting).

Of course this problem is worse when ordering/receiving larger trees. Many times these are two year old trees and the lower two year old wood won't have any live buds/shoots left. It wouldn't be so bad if the nurseries would start to train the trees for production at the nursery, but they simply prune off everything down low, so that you're forced to start the scaffolds higher up.

For the last few years, I've requested smaller peach trees from nurseries to avoid this problem. Sometimes they send smaller ones, sometimes not. This year I've ordered quite a few trees and requested them as small as possible. From the confirmations, it looks like that's what I'll be getting. Quite frankly, I don't know if there will be any negatives (other than maybe less early production) from such small trees, but perhaps I'll know more after a couple years.

In a cold environment like yours, extremely small peach trees may not put on enough growth the first season to be adequately hardy. I've heard small peach trees aren't quite as hardy as larger ones.