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Johnson County

Research-based Information You Can Trust — Localized for your needs

Johnson County
11811 S. Sunset Drive
Suite 1500
Olathe, KS 66061

(913) 715-7000
(913) 715-7005 fax

Map to our office

September Garden Calendar

Vegetables and Fruits

  • Continue to harvest vegetables
  • Pick apples and pears and store in a cool place to extend freshness
  • Harvest pumpkins when flesh is completely orange and avoid carrying by stem
  • Harvest winter squash when rind is hard enough to puncture with fingernail
  • Plant lettuce, spinach, and radishes
  • Remove weeds from garden plantings before going to seed
  • Herbs can be dug from garden and placed in pots for indoor use this winter
  • Remove small tomatoes from their vines to increase late development of more mature fruits


  • Plant spring flowering bulbs, tulips, daffodils, and others
  • Dig, divide, or plant peonies
  • Divide perennials, especially spring bloomers
  • Remove seedheads from perennials to prevent reseeding in the garden
  • Plant chrysanthemums for fall color
  • Dig gladiolus as foliage begins to yellow and air dry before storing for winter
  • Clean up garden areas to reduce insects and disease as plants dieback for winter
  • Enrich soil by adding organic matter such as peat moss or compost


  • Plant or sod new bluegrass or tall fescue lawns
  • Renovate bluegrass or tall fescue lawns by verticutting
  • Core aerate cool season turf
  • Fertilize cool season grasses with high nitrogen sources of fertilizer
  • Mow turf at 2 to 3 inches and sharpen blade for a clean cut

Trees and Shrubs

  • Plant trees and shrubs, deciduous and evergreen
  • Rake up fallen leaves and compost
  • Prune broken and dead branches from trees
  • Avoid pruning spring flowering shrubs such as lilac and forsythia to ensure spring flowers
  • Hand pick bagworms to reduce problem in future


  • Bring plants in before temperatures drop into the fifties
  • Clean and wash before moving indoors to reduce insects
  • Fertilize before winter conditions arrive and growth slows
  • Poinsettias can be forced into Christmas bloom by starting dark treatment of short days

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K-State Research and Extension Johnson County Master Gardener logo

Have questions? The Garden Hotline is staffed by trained EMG volunteers and Extension staff who will assist you with questions.

Phone: (913) 715-7050

Email: garden.help@jocogov.org