I planted a young Japanese maple 1 week ago and it is starting to look sickly - leaves are turning green and brown. I watered generously for first 3-4 days.
Certified GKH Gardening Expert
Since the tree is newly planted, I would suspect that it may be a little on the dry side. Newly planted trees require lots of water while they establish their roots. These articles should help: https://www.gardeningknowhow.com/ornamental/trees/tgen/watering-newly-planted-tree.htm, https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm