It doesn't matter how hot it can take if it's a tree that needs months of cold (below freezing most of the time) dormancy to survive. I'm sure, though, that there must be hundreds of 'pretty' trees around, tropical or semi-trop. that you could use without needing deciduous ones that have nothing but skinny bare branches for over half the year. As to heat tolerance, it will depend on the tree, your individual climate, care, etc.

While a small measure of chill unit accumulation occurs at temperatures above 45* F (7.2* C), virtually no accumulation of chill units occurs at temperatures below 32* F (0* C), and only little at temps below 34* F (1.1* C). 34 - 45* F is the optimum temperature range to satisfy the chill requirement that allows plants to pass from dormancy to quiescence or to begin growing with as much vitality as their stored energy status & cultural conditions allow.

Al

Hi Buddaboy. I live in the Philippines and it is situated 15N Latitude from the equator. We experience temperatures at around 35C the most and 18C the least. The hottest time we have here are at around April and May where there are cloudless skies and the temp ranges from 22 at night to 35 during the day. I tried growing pear varieties such as capri, taiwan hybrid and kieffer. These trees thrived in my yard potbound for about five years now. I say that the capri and kieffer are the ones that bloomed every year during late february. Though the trees do not show marked seasonality, but you can see that the trees drop some of their leaves during our "winter" and put into flower during the late part of it. By the way, they set fruit, but it stays in its hard unripe state until it falls off, thus does not ripe well. Well, if you are just after the blooms, it might work. I cannot say that their tree-neighbors in the north such as the maple may show their colors during our "fall" here, but I might keep you posted with regard to the observations that i might make with my newly-sprouted norway maple seedling. Best regards - Victor