Thanks chicken little. How do you store your grafted stock before moving outside? I put mine in the garage and wonder if maybe it got too cold. All my rootstocks lived, just the buds on scions never did anything, eventually just drying out and dying.
There are some differences depending on what and how you are grafting. Here are some general comments:
Nothing will preserve scion wood like the tree it is on before it is collected. You need to collect it before the buds begin to swell but I like to keep it on the tree until I have to collect it. Dipping the cut ends of the scions in Dr. Farwells or any grafting sealant will help keep them from drying out while in storage. I typically put them in a ziplock bag with some slightly damp sphagnum. If you get things too wet you can get mold. I don't seal the bag, I just fold it over. I put it in the crisper. Make sure you have no other fruit in the refrigerator with your scions.
With most grafting methods used on the bench, Whip & Tongue, Wedge, etc, the key is matching up the cambium layers. I like to use freezer tape when grafting things like apples with these techniques. It degrades in the field and you don't need to remove it like electrical tape. It has a coating on it that is water resistant which helps keep water from getting into the graft.
While I don't bother with easy to graft trees, I like to wrap scions with Parafilm-M before grafting them. This too helps keep the scion from drying out until it has had chance to callus with the rootstock. If you are having high success rates, don't bother, but it does provide more time.
Also keep in mind that there can be incompatibilities between rootstock and scions. For example, some combinations of oriental and European pears don't do well.
Timing can also be a factor. With some kinds of trees, I seem to get better results if the rootstock is actively growing. With others it seems that can work against you. For example, I've tried grafting some domestic apple scions to crabapple rootstock after the crabapples are actively growing. Because the crabs I was using leaf out much earlier than the domestic apples I was grafting, the trees wanted to push out more crab branches rather than pushing the scion. This usually occurs in a field situation not bench.
Having said that, I've also had some good success grafting early and putting the grafted trees immediately into 3 gal RB2s under lights and then acclimating them to the outdoors. This allows for a more controlled environment for the grafts to take and then a good growing season in the root pruning container to build a root system. There are both upsides and downsides to this approach.
Thanks,
Jack