I think (I'm sure someone will correct me if I am wrong) that sun is sun for the most part, as long as it's direct and not filtered through trees and such. Photosynthesis happens when the sunlight hits and isn't related to the heat or UV, which is much stronger in the afternoon. However, some plants basically shut down photosynthesis during the hot part of the day to conserve water, so for some plants that morning sun is better sun, but mostly what this would affect is your part-sun plants. Many of them can't take that hot afternoon sun, they prefer morning sun. I think it's more of a heat issue. So for areas that get part-sun but in the hot afternoon I generally pick plants that can take either full sun or part-shade. That way I know they can take the heat but don't need a full day of sun. I would wait and see how your plants fare with the changing conditions. If you keep a good eye on them you should see signs of distress (mostly wilting or browning) in those getting too much sun and those with too little will often just not grow well or have poor flower production. Usually they can be moved to a better location and will perk up. Plants don't always behave like the labels say they will so moving everything around before you know you need to might be a lot of unneccessary work. -Ais.

Mine (at my old house) was in full sun all day and thrived. I took cuttings to bring here and have put them in mostly sun and close to the garage to keep them from freezing. It worked but then a week ago or so, caterpillars got to them OVERNIGHT! but their on their way back after being sprayed.

This is to RB, since you seem to know Big Smile - I recently purchased 3 of them as a support for Children's Cancer Cure fund raiser. I have one in a shaded corner with only a short AM sun - she's doing great after a month there. 2 of them are planted in a W facing front strip that used to be shaded by a beautiful Ornamental Plum that just very recently had to be taken down (reoccurence of borer problem - controlled for a few years). I have been studying the sun exposure for a few days and have been, like a plant-nut that I am, shielding the Hostas and the 2 Big Smiles with umbrellas and lawn chairs when old mighty Sun hits the strip. I had purchased a Royal Raindrops Crab to replace the demised Orn. Plum but have to wait for it to provide the very much missed shade, do I have to move my 2 Big Smiles or will they toughen up some and with much TLC and H2O, to be able to handle a few hours of aft. sun? I love where they are now and can only imagine them when they grow up to be the handsome pretty Smiles that they are. Greatly appreciate your thoughts!!! Ditas

Thanks Brandon7 for post of your responses today. I am concerned about the big shade tree because a) it lives in what I think is a stressful spot (right next to the driveway), b) I may have a sewer pipe run through the yard which will run right next to the trunk on the other side from the driveway, and c)I just get a sinking feeling about it! My girlfriend, however, loves the tree. Add to that, I have had many trees cut down over this past year... she just doesn't have the tolerance to see another one go down. Given that I have all kinds of big trees that came with the house, I'd like to get some consistency with some of the more decorative trees. I love the bark on the Natchez, the drought tolerance, and the medium-large size...and the fact that these trees look their best when the rest of the greenery starts looking a bit worn from the summer heat by August. Maybe there are some disadvantages to the Crepes... please advise! Other than that, I have bought a few different types of Dogwoods, a Stewartia, a sunset red maple, paperbark maple, S. Magnolia Altus, Winter Red Hollies, Nellie Stevens Hollies and BlazerFoster Hollies. ... and natchez and dynamite red crepes. All purchased and planted in early spring. The Nellies can tolerate the partial sun, but in the area that I'm considering, I prefer the shape of the crepe. Brandon, or anyone else, I am happy to take advice on any or all of those plants.