Answer: Adequate drainage is important to raising a healthy Japanese maple. It would be dangerous to try and drill a hole in your lovely container - it could shatter. Instead, why not plant your maple in a plastic pot with drainage holes and set the pot inside your decorative pot? This way you can tip the pot to drain the excess moisture. Build up the inside of the pot with bubble wrap so you can set the potted maple on top (to raise it to the right level). Then either remove the maple to water it, or water it in place and periodically remove it to tip your clay pot and drain any accumulated water.
Best wishes with your new maple.
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