We have had some good hot weather here average of 97 the lowest temp. I have been t budding here since the heat started and it hasn't been phased at all. But I have had like 50 percent take on grafting. Any one have ideas why so low take on grafting.
Also why is I said it is bad to graft with hot weather ? I have had upwards in the 90 percent range on t budding.

Your scion will usually dry out before before a callus can occur, depending on the size of the scion the rootstock has to be able to supply your bud or scion wood, buds being small will usually stay moist enough as the wood for a graft will struggle.
I always use Anti-Stress 550 as a dip, even for budding

I have had a higher percent take from bark grafting during hot weather than from T budding--I also find that a foil shield to keep sun off of the graft will help during hot weather. However, I don't do much grafting during the summer because of the lower percentages

most of the old timers will tell you not to bud when the temp exceeds 90 degrees- the % of takes fall off dramatically