Had this Rootpac R rootstock get large on me and decided to make it into a massive multigraft tree. Half of the scions on this tree are plum/pluot and the other half are cherry with a Z-Dwarf interstem.
Cleft grafted interstem with a clefted top graft
Taped up
Parafilmed up and ready to go.
Eric those interstem grafts look perfect and I suspect you will get a very high take rate. I have been doing interstems a few years with apples and pears and I feel like I’m getting a pretty good grip on how to do these but I am totally lost when applying interstems to stone fruit. I have added 3 Japanese plums and one nectarine tree thinking they would not be so large a tree. Looks like I was wrong as these get 15-20’ high if allowed to do so. What variety of interstems are you using and are they compatible with both my plum and nectaring trees. Any advice will be appreciated. Bill
The interstem im using is a cherry/plum hybrid. Makes it possible for me to utilize this very strong and resilient plum rootstock to grow cherries on. I think its the future of cherry culture in my area as our soil and true cherry rootstocks do not mix.
Thanks, Bill
THAT looks like so much fun!!!
So are there any guidelins as to how long an interstem needs to be?
How many of these have you done and how many went on to produce what you wanted?
I must learn this. 
Where did you bought your Rootpac R rootstock from?
Since Rootpac R is a Myrobalan plum x Almond hybrid, you should let one branch flower and it produce fruit. I’m just curious to see what the fruit would look like.
These are my first attempts at interstems so I dont know a ton. I did the first of them 4-5 days ago and they are starting to take already…so it must be somewhat viable. Thats about all I can tell you so far sadly.
Rootpac-R is the preferred plum understock here in Phoenix. This was a linerstock burgundy plum tree that the scion died on and the root grew up. RSI Growers here in Phx is the nursery that uses it. At times they will sell me Hansen in liners that I graft to myself. But they are pretty stingy when it comes to RootpacR. Ive got plums on Hansen too but RootpacR is a really really good root here. Better than Hansen. I wish there was another source for it that didnt require me to buy 10,000 pieces to get it.
amadio good afternoon, when you make a interstem must leave a minimum of 20 centimeters between the rootstocks and cherry, ie the bridge has to be between 20 and 30 centimeters long to prevent sap rootpac-r comes as such the cherry.
some information rootpac-r:
Hello Matrix! Most of my interstems were about 10 centimeters. What will be the effect of less than 20-30 cm? Graft fail?
hello amadio, not that can occur when leaving just 10 centimeters, we’ll see how they evolve their grafts over the next two months, I understand that there are 3 options:
option A: 10 centimeters is enough to sap does not reach the cherry rootstocks and grafts grip well, no problem, everything ok.(not have to do anything more here)
Option B: grafts grab but poor bonding or welding may even have a delayed incompatibility within a few years (in this case, you can let outbreak also the graft bridge and next year the same cherry tree that already has grafted in the new branch to a height greater than 20cm)
Option C: all grafts are dried, in this case we have half of the job fact, you just have to let bud grafting bridge and grow and in September or next spring can regraft
That is great information. I will report back on what happens with them. Thank you Matrix.
I found these outlets ROOTPAC in United States:
http://www.agromillora.com/esl
http://www.agromillora.com/eng/florida
these rootstocks were created to be very resistant against various soil diseases(Rosellinia ,Armillaria,Agrobacterium, nematodes,Chlorosis,Salinity,Asphyxia,Cold).
these rootstocks make the fruit has more weight, the tree produces more and more trees are producing early can sell on the market the same range about 10 days before (get sold at a higher price).
rootstocks ROOTPAC series is formed by five different rootstocks:
rootpac 20:creates a small tree 20% the size of a standard tree, is an ideal potting rootstocks or where there is little space
rootpac 40:creates a small tree 40% the size of a standard tree,It is ideal for small gardens and super intensive cultivation
rootpac 70:creates a small tree 70% the size of a standard tree,It is ideal for intensive cultivation and gardens
rootpac 90:creates a standard tree,ideal for traditional cultivation and large spaces.
rootpac R:This rootstock is very vigorous, was created to be implanted where other rootstocks die from disease, its growth is very fast so that in a few years not notice who died trees in that area, being such a powerful tree can compete with the roots of trees around and grow in a few years so equaling the entire plantation
Thanks Matrix!
I will contact that company and see if they will sell smaller quantities. The big issue isnt finding a company that sells it, its finding one that will sell less than 10,000 trees.
It’s been over 3 weeks now since you grafted Eric. How are they looking?
Some of the interstems took, some didnt. About 50/50. Of the ones that had the cherry on the interstem fail, the actual interstem piece took…so ill have to regraft at some point. Been a rather fun project.
Do you think those that failed are incompatible between scion and interstem or just failed for other reasons?
Well as matrix pointed out the interstem I used was a little short. Could have something to do with that…dont know. Its the first time I have used the technique so im feeling my way thru.
If I had to make a guess it just failed because doing two grafts at once is inherently a tricky deal. The scion at the end isnt getting sap and nutrients pumping to it like you would on a normal single graft. I havent had a single interstem section not take, just a few of the end scions didnt live.
Thanks Eric. I’m going to try a few inter-stems on plums later on and I would like to shorten the learning curve as much as possible. Looking forward to your updates as to what works or what is questionable. As mentioned before my inter-stems have been between apples and pears which might be completely different than stone fruit. Bill
Hey guys,
Looking to see if anyone else had any success here. Heat in the soil is our main issue with traditional cherry rootstocks in my location, and i was thinking of using something like Nadia as an inter-stem. Is it legal, patent wise, to use a patented variety as an inter-stem only, and not for fruit production?