So, do you find leaf burn common with Acer Palmatum in Florida? - and if so, is there a particular solution that you have found works well to alleviate this problem?
Well, we really are limited on which varieties we can grow. We do grow about 15 varieties, however. Kashima, Kyohime, murisaki kyohime, arakawa, seriu, among a few others.
I have a few more I'd like to try, but its hard finding the ones I want to try in the states. A few things I've found is
1) organic fertilizer only except for early spring before it gets hot. The salts in chemical fertilizers seems to desiccate root tips which in turn exacerbates the summer leaf burn.
2) repot yearly in a bonsai pot or they fill up roots the second year unless in very large pots by the middle of second summer which tends to get leaf burn
3) the dyna gro product "protekt" seems to really help slow or in even some cases stop leaf burn.
4) pot in slightly deeper pots to also give roots a little more buffer. Exp if it is still in development.
5)keep them in partial shade from May on or 90+ degrees whatever happens first.
6) this one is still in study and I don't think I need to do it as soon since I am now in an area that keeps a bit colder for longer, But I used to defoliate the leafs as soon as the leaves started to change in the fall, and put them in deeper shade and keep them on the dry side.
You lose a lot of beautiful fall colors, but it helps keep the all important vigor up.
Also, I don't defoliate as I should mid summer to keep vigor up, but that is mostly because of the bad fertilizer programs and incorrect soil blends of 10-15 years ago being incorrect for our area. Ill start to utilize it now on strong plants now that I have a better understanding of our growing conditions in our area. My mentor also lives in Deland and has been growing Japanese maples in central Florida for over 30 years, so I know they grow here fine.
The one thing I can say 100% full sun is NOT Japanese maples friend. in fact growing under 50-70% shade during summer months is best. Summer in Florida is a whole different animal than anywhere elses full sun.
This is what I know so far.
Jason