July or August - once you have viable budwood you can do T or chip buds. To see if your budwood is viable pull off a leaf and if it looks like there is a completely formed bud by the base of the petiole, the budwood is viable.

Scott

I have read in more than one place that peach trees should be budded in Summer not grafted in the Spring like other trees but I can't figure out where that comes from. I have seven fruiting peach trees on various plum and seedling peach rootstock six of which I grafted with cleft grafts in the Spring. They're no more difficult than plums. I don't know why budding is supposed to be preferable to ordinary grafting in peaches. Anybody have an answer?

Peaches are one of the hardest fruits to graft in the spring since they are much more temperature sensitive. I'll let you decide if you are luckier or just plain better than average :-) If they are grafted in a period where the high temps are low/mid 80's they will generally take. Even when grafted in the right temperature range the odds are lower than with other fruits.

Scott