Tips for September – the fall planting month


  • Plant spring-blooming bulbs – one of fall’s exciting activities

  • Plant fall flowers (colchicum and crocus bulbs, pots of aster, biennial seeds, and fall pansies)

  • Plant ornamental grasses

  • Fertilize roses for the last time to allow them to harden off before winter; continue deadheading

  • Start edging and mulching beds; be sure they are weed free; clean out faded flowers and vegetables

  • Divide overcrowded perennials


  • Plant (or transplant) cool crops (arugula, broccoli, cabbage, cauliflower, lettuce)

  • Clean and prepare cold frame for fall/winter use


  • Install new lawns and keep moist

  • Dethatch and/or aerate mature lawns if needed

  • Have your soil tested to determine the pH (6.2-6.5 is desirable) – now is the time to apply lime if your pH is too low


  • Plant roses, shrubs, and trees

  • Prune hedges if overgrown, but only minimally, so not to overdo before winter

  • Do not fertilize shrubs or trees so they can go dormant and not put out new growth that cannot harden off before winter

  • Plant and/or transplant broadleaf evergreens (hollies, rhododendrons)

  • Watch for bagworms, fall webworms and tent caterpillars – and destroy


It’s time to switch gears and begin preparing for winter! Many trees and shrubs do best when planted in the fall – and it’s time to begin preparing for winter.

Fall is the time that insects come indoors to hibernate. Seal cracks and crevices around your foundation, doors, and windows. For infestations of ladybugs or boxelder bugs, your vacuum cleaner is the best solution. Spiders are beneficial insects, so capture them and release them outside if possible.


Visit the Loudoun County Master Gardener Demonstration Garden at Ida Lee Park in Leesburg to see various gardens and new planting techniques.

Contact the Loudoun County Master Gardener Help Desk with your questions:  703-771-5150 or

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