Hi,
Here lately the sun tries to make a come back. On those days trees and cuttings will dehydrate. On a cloudy day, they won't as much.
So watering should be adapted to the outside weather.
Now, to make it simple, I would put them in a greenhouse - there some small ones for raising tomato plants.
Put the greenhouse in a shady / half shady spot .
I have 2 pots with cuttings in my tomato greenhouse and so far so good.
One of them I was about to toss it because the stem looked rotted , but there was a little green weed coming out of the dirt. The leaves were thick and I recognized her as a root-shoot .
So for me a greenhouse is the easiest way to go, especially since the humidity will be higher on the coming dry summer days.
Good luck !