My earlier post was maybe confusing. When I said too dry, I meant while still bare, before potting or planting. But that appears to not be the problem. My guess now is drowning. btw, the grafts didn't necessarily take. They will put out a little growth from the energy stored in the scion. Make it a point to read this forum every day. Also find the potted plant forum and read there too. Better to start them in thier final location if you can. I did some for my brother this year. He lives a couple hours away. I watered the soil while mixing it about to get the moisture I wanted then put the dirt in pots, then put in the root stocks and mulched them. I kept them out of the rain and dribbled a little water on them just a few times in 6 weeks. I graft when the rootstock is breaking dormancy and preferably the scion is not, but if it is that's OK too. I transplanted my bros trees 6 weeks later. the roots had not started to circle in the pot and the trees took right off. I have a tree in my yard that I bought from a nursury and it still suffers from roots that were badly balled up encircling the pot. I cut them in 1/4's as is the rule, but the tree still has not got on track.

Will, I think it's best to consider the needs of the roots and tops of the plant separately. The USDA zone rating is a rough geuss but as you know, with so many other factors coming into play as well (wind, wet soil, on and on...) Here's an interesting example from the same webpage you quoted from above: "Cedrus atlantica, brevifolia, and libani are all grafted onto Cedrus deodara, the least hardy of the three. There are several reasons for this choice. The hardiness is not a factor since the deodara root system in the ground is at least as hardy as any Cedrus cultivar above ground. Secondly, the root system is more fibrous and better developed than in the other species making it a much better choice for nursery use." In this example, the top is least hardy, but the roots are most hardy, and the species is the preferred understock. I geuss this all gets at your fourth question to illustrate that you cannot make a plant "more hardy" by choice of rootstock, unless the limiting factor is the hardiness of the roots (not the top) in the first place. I geuss others already made this point more concisely - just wanted to add my two cents and what I thought was an interesting and illuminating example. Alex

To verify my scion wood was viable I used American plum, sand plum, myrobalan plum, Canadian bounty plum, and goose plum as controls. Canadian bounty plum took the grafts 60% of the time, American plum 70%, myrobalan plum 20%, Goose plum 0% so far. Prunus Besseyi grafts are taking about 70% of the time. The great news is its tree specific so if one graft fails they all fail even if I made three or four. If they take they all take 100% of the time. That implies that I did ok with the grafting of the stone fruits but they may be incompatible since they are genetically different plums grown from seed. Growing besseyi from cuttings would resolve that variable issue. I have a wild purple plum I plan to experiment with this next year. I tried one unsuccessful graft to it this year but was out of scion wood. I have 30+ of them growing.

Oh, definitely the rootstock, sorry I didn't make that clear. edit: So I grafted the two rootstocks. I think one was a M7, and the other an M26, and I grafted a Gravenstein, and a Honeycrisp. I have no idea what I'm doing, and really just experimenting. I used cleft grafts, and it seemed to go really well. Nice tight cambium layer contact. I think cleft grafts are the beginners graft of choice :-)....well, this beginner anyway. I potted one immediately, and I put the other in my garage in some wet newspaper and a little potting mix. I put the pot outside in the shade. Is the pot ok in the shade, or can I give it some sun?