August 1st: Last day for heavy summer pruning of rhododendrons, azaleas, forsythia and other spring-flowering shrubs. Also time to reapply slow-release dry fertilizer to your pots of annuals.
August 15th through September 15th: Time to divide and replant overgrown clumps of perennials.
August 15th through October 1st: Ideal time for re-seeding an old lawn or seeding a new lawn.
September 1st: Last day for trimming of hedges
October 1st through Thanksgiving: Time to plant spring bulbs.
November 15th through December 1st: Time to apply your last lawn fertilization.
November 15th through December 1st: Time to remulch perennial beds.