It depends on what type of Japanese Acer it is as to how much direct sunlight they can tolerate. I would probably put them in partial direct sunlight, maybe a lightly shaded area. But there are different types of Japanese Acers. I had one that received lots of sunlight and it did very well but had thin leaf blades, and I had another one with the dark red leaves that look like pot leaves and that one did well in a shaded area, but it was near a creek and beavers ate it up to pieces...

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