..Peach, Apricot, Cherry, and not so much plum:

In application to cherry of over 10 years ago when I started a grafting and collection project of North American wild cherry, sweet cherry types and hybrids I had run into nothing but big issues getting my scions to graft. I had never run into problems before using apples or pears. So because I could not find the requirements from other sources of books or internet services I then turned the question over to the late Jerry Lehman who had mastered a living from fruiting trees and here is (in part) the record.

"Sweet cherries break flower and vegetative buds very early and if stored at 45 degrees will actually start expanding in the fridge. Once the bud has started to swell the grafting reliability drops very quickly. Cut the scionwood while still **winter and store very cold. Then graft after the understock bark is in the slip. At least this this has been my Prunus observations and success formula after many failures."  //end of email paste.

I installed a ** so note: winter; PNW;
Jerry was not a western resident. Change the word **winter to "While Still Autumn"!

For sources of scionwood another risk to avoid are trees that are stressed such as growing outdoors in pots. An indoor tree or something outdoors & later treated for a few hours using aquarium and fish antibiotics prior to storing may be okay too.

As I said earlier the forecast going forward looks messy so think today. Later towards or after the new year think "east of Cascades". Sub-freezing temperatures if not too severe are okay.

John S said
It seems to be about the right time to cut scions.  Most of the leaves have fallen. It is December already. The only thing holding me back is that we haven't had any of those really cold days yet.  

Hi John,

Are you sure it might not be too early?  I always believe in cutting scionwood at approximately "the coldest" part of winter when you can have no doubt that your scion donor is at its "dormantest".   For those of us who live close to nature, we can usually get a sense of that from our own experience and observations over time in a given area.  However, many of us are aware of just how unpredictable our weather is becoming due to global warming which affects different parts of our planet in different ways.  It is becoming difficult to assess "just when" the time might be right.  At our place in SW Washington, for example, our winter so far has been relatively mild.  Yes, the fruit trees have gone deciduous, but we have not yet had a truly cold period yet.  Here, our normal coldest month is February, and that is usually when I've collected scion wood.  In the last 21 years, our coldest temperature was (as I recall) 6.8 degrees.  Right now it's 25.  I'll probably wait until at least late January to see how our "winter" is shaping-up.  I think that you're in the best position to determine your best scion-cutting time, assuming that you have long experience there.

I like Rooney's comments in relation to the cherries.  I love cherries and eventually want to have a diversity of them, but they are so profoundly persnickety when it comes to grafting.  There's a true art there that I haven't yet grasped under my conditions.  

     ....It's not just "live and learn", as they say:  It's observe, and study, and experiment, in order to finally meet with a reasonable measure of success.  In each of our unique microclimates, we have to be our own objective scientists.  Best wishes for ultimate success.  That's all any of us want.

Reinettes

Reinettes: The problem with cutting scions "on approximately the coldest  times" of the year are disease and as it relates to favorable conditions for disease. So you can't go about your experiments the way you think you can. PNWet and cool, both of which promote pseudomonas syringae cv. syringae (short PSS), which is a destructive gram negative bacteria that inhabit trees to lawn grass. Other below freezing real winter climates put a stall against this including all other pathogenic diseases. I am a doubter type myself, and it's a complex maize of work to find, but the papers are out there. Here our outdoor trees, certainly prunus, are at the stage of taking on a systemic invasion that never goes well until maybe warmer weather arrives or death.

I took in the last of my scions today. I took many from the passes 5 weeks ago. Attached leaves in cool wet are worse for especially when the areas are abandoned and have had soils dried. The situation with leaves and dry soils demonstrates negative xylem vessel pressure compared to the surrounding air (ie. a vacuum). Part of the reason in the summer trees halt growth is prevention of cavitation (damage) to xylem vessels collapsing. The other is the conservation of energy otherwise used to support growth is reprogrammed to defend from bio-predation. (ie. PSS vacuumed into the tree)

I will leave the scions that I took inside the last 5 weeks inserted in a shelter with bottoms in a shallow amount of water to receive chilling hours until the first day of winter. Then they will be put under the cold spell as Jerry explained, but I go 25-26F just several degrees below freezing, which is okay for almost everything.

There are too many places that I sourced my success in grafting cherry to mention. What counts is that I rarely have an issue grafting cherry anymore. One of the things I learned concerning chill is interesting enough to mention here though. Pear seeds can sometimes be seen germinating with tiny roots from store bought pear fruits around January if I remember right because I tried it. Books have said they germinate even though these seeds lack the chill hours. They grew for me in several pots all through the next (first) growing season very very slowly. This was expected and it was true, they gained to about 8-9 inches. Were they to have been spring budded (which I didn't) on another pear that received proper chill hours those buds would have grown normally (per book). Come the following (full 2nd) season after the 8-9 inch potted trees received the right chill hours all went 100% back to normal.

It's good to question the way I did but don't get hung up on it. It's not really an important thing to accomplish of chill hours since they are an independent operation and will have very little delay effect on the scion.

John S said
Rooney,

You know I have prunus. You have been here more than once and shared a purchase with me of rootstock, borrowed the flower pollen on others and given me plants. I haven't started yet because it's been so wet.  I want to wait until it's pretty dry. 

John S

PDX OR  

So the purchase of rootstock was gisela-6 cherry stock 20 months ago. Half or so of mine died fast because of the very undeveloped roots. So I have two in good shape, never attempted the graft yet, but only have plans for the one. I dug them loose for now then I aim for spring grafting method for the one. Information gleaned from other cherry experts and my own and per Daniel above -suggest that cherry rootstocks (probably peach as well) go into shock when messing around with roots (ie. nursery re-potting). Gradually recovering after a full month's time growing is necessary.

At the HOS grafting events in the spring I always tried to push this peach/cherry advice forward to the customer. This same issue may also be good reason why wholesalers developed plum roots like the adara and zeestem plum stock. In which case you have a steadier stock to stick graft cherry on.

I worked on the Rombough Grape Farm recently. I gathered boxes of chinese quinces and since you may like them you can have a box with the other leftover G6 cherry root I described for you in the first paragraph.

per post-6
John S said
...
I saw some information from the Agrarian Sharing Network on Facebook that it is still too early for pears. They recommend Jan 1 for most things, but Jan 15 for pears.  I saw this after my post.
...

As always it's more important for us to avoid diseased sites. For us it's PNWet. But we have no choice so follow the guidance of our instructors such as Joseph Postman. Every spring he helped our now retired board leader and the rest of us secure a list of named pear cultivars for the least sub-set of problems. For convenience this was a few weeks prior to the exchanges that were. But when we (if you do have) have the proper refrigeration equipment then it is indeed possible to replicate any one (Corvallis OR) of what he has. I know it citing myself; the short internode cultivar I got from Joe around March (generation-2 of 'Nain Vert' as you may recall another topic) as exampled of one taken too late. Only one of six grafts survived on me.

I know chill hour requirements are a confusing topic to many, then, you will ultimately be best to ignore chill and invest your time looking for ways of replicating any especially hard to graft cultivar by looking to store them longer and cooler. By December 1 in PNW is okay. You will avoid most of the disease that is systemic here in trees that are most prone. If storing as low as 26F the way I do the properly chilled rootstock will rectify the scions from having not experienced proper chill hours.

Here is a link that might be useful. researchgate.net article

PS. I did see your above nested per post-12 comment that you succeeded your G6. Good job!

It's another reminder to myself too that I have yet to contact George Barton who I talked with last year who promised me scions from his 'satsuma' plum that he raves about.

If you like sour cherries then the productive 'montmorency' grafted on your new precocious 'gisela-6' rootstocks we split would do at least as well as I have been shown 'mesabi' does on 'krymsk-86'. The latter of which I have seen as being heavy to bear at Purvis' nursery in Idaho. Mesabi is a duke 50% sour cherry, so if your interested in that I have sourced him in Idaho and another establishment (about the k-86) in Washington for the stock and you should let me know. The tree was seen fully loaded as a four foot tree!

All these cherry stocks pose issues grafting them too early in the year. Too many details to list them all. Our best hope here may well be krymsk-1 plum stock with either the adara or zeestem plum wood (in- between) that are cherry to plum compatible.

Edit 1-4-2021:
Sorry John. This two days old post that I wrote 'krymsk-86' and 'k-86' should be correctly "krymsk-6" (pdf) as witnessed at Idaho with 'mesabi' grafted on. My mistake. But I still mean the Washington nursery still carries the correct krymsk-6 rootstock for the idea of using mesabi. If interested let me know.