September Garden Calendar for the Midwest

As September brings us closer to fall, we find there are plenty of fall garden tasks that we can begin to work on. I will cover lawn care, flowers, vegetables and fruits, trees and shrubs, and houseplants. Info on winter flower beds and landscapes may also be helpful.

September garden calendar

September Garden Tasks

September LAWNS

  • Seed bluegrass or tall fescue lawns early in the month for best results.
  • Sod new lawns or dead spots for quick recovery
  • Renovate bluegrass or tall fescue by verticutting then overseeding.
  • Core aerate cool season turf to aid in root development and thatch breakdown.
  • Fertilize cool season grasses with high nitrogen sources of fertilizer.
  • Mow turf at 2 to 3 inches and sharpen mower blade for a clean cut.
  • Continue to mow zoysia but o not fertilize or aerate this late in the season.
  • Maintain lawn mower by changing oil and air filter.

September FLOWERS

  • Plant spring flowering bulbs, tulips, daffodils and others.
  • Dig, divide, or plant peonies.
  • Divide perennials, especially spring bloomers.
  • Remove seed heads 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 garden areas to reduce insects and disease as plants dieback for winter.
  • Enrich soil by adding organic matter such as compost.
  • Soil test for the next growing season.


  • 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 the stem.
  • Harvest winter squash when the rind cannot be punctured with your fingernail.
  • Plant lettuce, spinach and radishes for fall harvest.
  • Remove weeds from plantings before going to seed.
  • Tender herbs can be dug from the garden and placed in pots for indoor use this winter.
  • Remove weeds from garden plantings before going to seed.
  • Tender herbs can be dug from the garden and placed in pots for indoor use this winter.
  • Remove small tomatoes to increase late development of more mature fruits.
  • Spade or till garden plots incorporating fallen leaves or grass clippings to improve soil.plant garlic cloves for next year’s crop.

September 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 flowers shrubs to ensure spring flowers.
  • Handpick bagworms to reduce problem infestation next year.


  • Bring plants in before temperatures drop in to the 50’s.
  • Clean and wash before moving indoors to reduce insects.
  • Fertilize before winter conditions arrive and growth slows.
  • Force poinsettias into Christmas bloom by starting dark treatment.

*Information gathered from Johnson County K-State Research and Extension. They offer free information fact sheets, and can be visited at You will find many helpful articles at for all your yard and gardening needs.

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