I would wait until september, when it starts to cool down.

i dont know timing in your zone ...

but in my MI ... one of the keys is night heat ... a cool recovery period for whatever happened during the day ...

so i used to wait until at least sept .. so the nights were falling into the 50s ...

one of the biggest advantages was .. in fall .. the soil wont be drying every day or so ... a deep good soaking at planting .. and then mulch.. and there were good odds ... that i might not have to water again until next summer .. and when you are planting all over a large yard ... that is a great benefit ...

there was one fall ... that was actually a drought ... and i did water again in november ... you water when the trees need water ... and you dont put the hoses away october first.. just because ... but i did have to disconnect them from the house and remove the wand.. to make sure the hose could let out water pressure and not freeze and burst overnight ...

in your zone.. the freezing probably isnt an issue until much later .... just fyi ..

ken

The oaks seem to have finally set terminal buds, although the upper parts of the stems are still soft and green.

The redbud is still shooting skyward. And sideways, as redbuds do.

I would do it now.

Agree with planting now. I have had perfect results with container trees planted in August to early September. You probably won't need to do much supplemental watering as you get into mid September and beyond.

I would do it now also. How hard is it going to be to water three trees that were in 5 gal pots? Way easier than if they were kept in pots.

Good point. In the pots I've had to water every 2-4 days depending how hot and sunny it is.