Answer: A common maple problem is leaf scorch. This is usually a result of hot afternoon sunshine, but it can also be caused by fertilizer burn (salts can especially build up in containerized plants). I'd move the maple to a site that gets morning sun but only filtered afternoon sun (or bright afternoon shade). When you fertilize, use a water soluable fertilizer (such as Peter's or Miracle-Gro), and to keep salts from building up in the container, leach the soil every few months by immersing the container in a larger container of water for 15-20 minutes.
Best wishes with your maple.
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