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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

Office Hours:

Monday - Friday,
8:30 a.m. - 5 p.m.

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

Map to our office

K-State Research and Extension is committed to making its services, activities and programs accessible to all participants. Reasonable accommodations for persons with disabilities may be requested by contacting Johnson County Extension at (913)715-7000. Notify staff of accommodation needs as early as possible.

Kansas State University Agricultural Experiment Station and Cooperative Extension Service

K-State Research and Extension is an equal opportunity provider and employer.

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

Return to Garden Calendar

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