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Fall Gardening Chores: September

Photo courtesy of Flickr cc/ Herry Lawford
photo courtesy of Flickr cc/ Herry Lawford


  • Complete orders of spring-flowering bulbs and other plants for fall planting
  • Assess areas in the garden that may need new or replacement planting
  • Work on your landscape plan for fall planting of trees and shrubs
  • Take garden notes and photographs to plan future planting

Chores and Maintenance:

  • If it is dry, practice water-wise horticultural techniques
  • Dethatch and aerate lawns to promote root growth
  • Mow lawns regularly to keep grass 2 1/2 - 3 inches high
  • Complete spot seeding and lawn restoration by September 15th
  • Collect seed from perennials and annuals
  • Cut flowers for drying: yarrow, strawflower, gomphrena, cockscomb, etc.
  • Remove and compost spent annuals and fallen leaves
  • Aerate and moisten compost pile to speed decomposition
  • Check for insect pests and treat accordingly
  • Remove fallen leaves and debris that can harbor insect pests and disease
  • Apply deer repellent
  • Take in tender aquatic plants and tropical fish from ponds
  • Begin to feed birds
Cut flowers, like Gomphrena, Qis, for drying; photo by Danielle Colburn
Cut flowers, like Gomphrena QisTM , for drying; photo by Danielle Culburn


  • Plant and transplant broad-leaved and needle-leaved evergreens through October 15th
  • Propagate herbs from new growth and transplant into pots for winter use
  • Continue to divide and transplant early-blooming perennials
  • Divide daylilies after flowering
  • Plant lilies
  • Sow hardy annuals in prepared planting beds
  • If weather turns cool, begin planting spring-flowering bulbs (wait until late October for tulips)
  • Plant late season ornamentals, like ornamental kale and cabbage for fall color
  • Sow parsley, radish, carrot, lettuce and onions
  • Plant out seeding biennials
Divide daylilies after flowering
Divide daylilies (Hemerocallis) after flowering

Pruning and Fertilizing:

  • Prune rambling roses
  • Remove diseased and dead rose canes
  • Root prune wisteria that doesn't bloom
  • Add organic matter, such as manure, compost and/or leaf mold to improve garden soil
  • Fertilize roses one last time
  • Fertilize lawns with organic fertilizer to stimulate winter root development
September is the month to root-prune wisteria that does not bloom; photo by Ivo Vermeulen
September is the month to root-prune wisteria that does not bloom; photo by Ivo Vermeulen


  • If frost threatens, pinch back houseplants and treat for insect pests as necessary before bringing indoors
  • Begin to force poinsettias for holiday display; move indoors to a sunny location and cover for 14 hours each night for a period of 6 to 10 weeks
  • Take cuttings of begonias, geraniums, solenostemon (coleus), etc. to grow as houseplants


*These gardening tips are applicable for an average year in the southeastern New York region: USDA Plant Hardiness Zones 7a and 7b, which include New York City, Northern New Jersey, most of Rockland and Westchester Counties, Southern Connecticut, and parts of Long Island. Plant hardiness zones refer to geographic areas where the growing season of plants is determined by the time of killing frosts in the spring and fall. Even within zones, climatic factors such as altitude, proximity to water, wind exposure, winter sun exposure and snow cover contribute to the existence of different "microclimates" and can influence plant adaptability.

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