Robert Baerg

In our yard proper about 60 and in the orchard about  700. Mostly apples and plums and a few pears. We also have lots of raspberries, black currants, goose berries and haskaps.

In a cold climate (Mongolia) we need to keep the entire vine compact and close to the ground as we have to cover them for the winter. So I find that spur pruning is best suited for our situation. Concord, Amurensis, Riparia and Valiant/C-16 do well with this method.

I would go with something in the alder family.

We plant a lot of cherries (sandcherry, nanking cherry and others) and plums every year. Most of the cherry varieties are used as rootstocks for plums and apricots. In August I collect the new seed and dry it and then put them in ziploc bags in the fridge. Then in January I will take the seeds and soak them for 24 hours before putting them in another ziploc bag containing a slightly moist stratification medium. I have tried using clean sand, perlite, and coconut coir. The sand and the coconut coir gave me the most consistent results. There is also a good color contrast between the color of the roots and the medium so you can easily see when the seeds start to germinate. Over the years I have kept track of all the "stratification start" and "germination start" dates so now I know when to start my seeds in order to get them to germinate when I want them to. So I stratify most of my Prunus seeds at the beginning of January and they will begin to germinate 2 to 3+ months later, depending on the species. My plums/chums are on the 3 month end of that range. I generally get good rates of germination with this method. For the last 3 years I have also tried Fall seeding of the same varieties in seed beds. Germination rates, particularly with the plums, has been poor and erratic, with numerous seeds taking 2 years to germinate if they do at all. So I am now germinating almost all of my seeds in the fridge and then planting the seedlings out in beds as soon as the weather allows.

My experience thus far with grafting plums onto 1 year old sand cherries has been that a scion or bud from a mature tree will begin flowering/fruiting after 1 to 2 years. Two years ago I took buds from 6 seed grown plum varieties and grafted them onto 1 year old sand cherries and now two years on they have not yet begun to flower. My experience with grafting apple scions and buds from mature trees onto 1 year seedlings or onto 10 year old mature Siberian crabapples has been that the graft will not begin to flower for at least 4 to 5 years. The only exceptions to this is when I have grafted a bud or scion containing flowers. In one such case last year, on a large Siberian Crab, the August 2019 grafted bud flowered and produced fruit in 2020. In 2021 this same branch is growing well but did not produce any flowers. This year I have a number of 1 year old seed grown apple varieties and I will be bud grafting them onto a variety of rootstocks to see if I can fast track to the flowering stage. From my experience though I think it will be at least 4 to 5 years to see first flowers.

Just a quick update on the plum situation here. My prunus nigra bloomed for the first time, with about 30 to 40 flowers and lo and behold this year all of my plum trees have significant fruit on them.

So I am in Northern Mongolia, very near the Russian border. We are zone 2/3 by temps and vegetation that I see here. We started a permaculture project here about 7 years ago and are hoping to develop new fruit varieties, that are viable in this climate, through cross pollination and seed propagation. Being zone 2/3 really narrows the selection of cultivar choices available to us, particularly if you want larger apples. So the names of our apples will not be familiar to most people, unless you live in colder climates.  We currently have about 50 varieties of apples that we are working with, with fruit size ranging from 0.6cm to 8.5cm. Most of our varieties have their origins in the Canadian prairies and the northern US states. We also have a number of Russian varieties from Siberia. We have wild Malus baccata (Siberian Crabapple) growing right in our area and we are collecting seeds from these trees and are growing these as rootstocks for grafting. We grafted our first trees in 2015 with the Rescue apple and these started fruiting 2 years ago. This last year, 2020, 5 more varieties started to produce fruit with one tree producing a 235g apple. To date, Rescue and September Ruby have been the best performers. We are currently developing an overgrazed 10ha piece of land, using "indigenized" permaculture methods. We are hoping to develop a number of food forest areas within this area and apples will be one of the main fruit components. We are strong proponents of the need for diversity in fruit (plant) genetics and as such we are collecting all the seeds from our fruit and growing it out with the goal of producing more indigenous, locally adapted fruit varieties. We currently have 6 apple varieties flowering and they are mixing with the local baccata genetics to produce ??? So much FUN! To date we have grown several thousand Baccatas and we can see that there is a fair bit of genetic variability within  this group even though they have been growing in isolation from all other Malus species.The fruit on one tree, picture attached, was very unique in that all the fruit grew as doublets or triplets. We have collected the seed from these and will see if this is a characteristic that will reproduce.
We are also in line to potentially get some wild Malus sieversii seeds (Kazakhstan sourced) this fall.
There had been a link posted to the apple forum about getting Malus sieversii germplasm material from the USDA site in Geneva, New York. I followed this up and eventually got a response saying that their Geneva site had had a fire blight "pandemic" this last year and as such no grafting material would be shipped in the near future. I had also heard that they were giving out M.sieversii seed, collected from a planted stand of 1000+ trees, to people who were interested. After a bit more chasing I made a connection with the "Botany of Desire Seed Program" and it is from this program that these seeds are made available. For anyone interested in such seedy stuff the person to contact is Dawn Dellafave (dawn.dellefave@usda.gov).

I have Prunus nigra growing here now but it has not flowered yet. Hopefully they will begin to bloom this spring. In Canada it has proven to be the best pollinator across almost all the plum varieties. And yes we have wild apricots, Prunus sibirica, here. We have used it for plum rootstocks with mixed results. Our sandcherries have proven to be the best plum rootstock so far. I am keeping this thread just for plum discussions but we also have several varieties of apricots growing on sibirica rootstocks and are trying to get some of those Kazakhstan varieties. We also have a bunch of apples varieties growing and are hoping to get some of the Kazakh apple varieties this fall.

So I am in Northern Mongolia, very near the Russian border. We are zone 2/3 by temps and vegetation that I see here. We started a permaculture project here about 7 years ago and are hoping to develop new fruit varieties, that are viable in this climate, through cross pollination and seed propagation. About 5 years ago I acquired my first plums, 7 yellow plum seeds from a government research station about 100km south of us. They were reportedly from the Ussuri River area in eastern Russia. I grew all 7 of them and they produced 7 distinctly different plum trees/bushes. Some are low growing, others more upright, some have 1 to 2 flowers per cluster while others have 2 to 5 flowers per cluster. The first tree, UH-1X,  started flowering and fruiting 3 years ago and produced about 40 small, dark red with red flesh, cling stone fruit. Two of the other trees started flowering 2 years ago but did not set fruit, one of them, UH-4X, died due to some unknown soil issue,  while UH-1X produced about 150 fruit. This year 4 of the remaining UH plums flowered and 3, UH-1, 3 and 5 produced fruit. The fruit on UH-3X and 5X larger than UH-1X and both were a yellow/orange/red with yellow flesh and free stone. UH-2X bloomed profusely but did not set a single fruit even though all of these plums are growing within meters of each other and there was also an American plum and sandcherries blooming at the same time. We also had a bee hive in the middle of all of this. So it would appear that UH-2X is having a pollination problem. 2 years ago we brought in plum and chum branches from Saskatchewan and Russia and now have a total of 35 varieties growing. We are expecting some of these to bloom this year and see if some of these will pollinate UH-2X. Last year we collected about 500 seeds from our plum harvest and will be growing them out this spring. With our sandcherries and various plums, with our bees, we have a fair mix of pollen moving around. We have a 10ha (22ac) piece of land where we are doing our tree trials.

Thanks Steve for starting all these great fruit forums! My passion as well. I will post some stuff in the next few days.