Japanese maple mutant

[BrightsideB]

FWIW, threadleaf and laceleaf JMs don't do all that well in Southern locations. Their leaves can't take the summer sun. The examples of both planted here in Va. have typically brown crispy foliage by mid-August. A shallow pot makes that tendency even worse.

I’ve noticed that as well. I give my maples direct morning sun from about 8am to 11-12am to minimize the heat damage. Usually go home on my lunch breaks to water foliage and roots during mid summer to cool them down and give my tree’s more water. It has helped a lot. But I’ve definitely seen what you are talking about. And now that I think about it is mostly the highly serrated leaf cultivars and the ones you stated that seem to get the most damaged.