I have a well established(10+ years) green lacy Japanese maple that is 4 feet tall and 5 feet wide in my well protected backyard. It was planted in full shade and has begun getting a little more light in the past two years(neighbours maple tree was removed) but it would still be considered shade. The edges of the lacy leaves are turning brown on the entire tree. I mulched the tree with cedar mulch this spring for the first time. I am located in Etobicoke just south of Bloor. What am I doing wrong?
Thank you for contacting the Toronto master gardeners with your inquiry concerning your Japanese Maple.
From you photo it appears that your japanese maple is suffering from leaf scorch. We have experienced heat waves and, notably, extremely high UV indexes, this summer and many trees are suffering fron leaf scorch as a result. Even though your tree is in shade it has been experiencing more sun in the last two years ever since your neighbours tree has been removed. Browning japanese maple leaves is a question we’ve answered for other gardeners, so let me refer you to this detailed answer here