They should be fertilized with a 30-10-10 from May long to July 15th. You don’t want to encourage new growth late in the season or they won't shut down properly and you will end up with tip kill in the spring.

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Water your new Maples and Birches well from May to August. In September water you tree sparingly to encourage the tree to go into dormancy.

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Maple or Birch trees should only be pruned when in full leaf (July and August). If you prune too early or too late the tree will bleed and attract insects, which can lead to problems.

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