September is a month of change for home gardeners as harvests of vegetables and herbs continue but the days become shorter and fall gardening and landscaping begins.

“Summer annuals look fantastic right now,” says UT Gardens Director Sue Hamilton, “but gardeners really need to pull them out so they can set out cool-season annuals and perennials. If you get them established in September, they’ll be extra robust and produce more flowers.”

Other gardening tips that Hamilton has for September chores include:

  • Now’s the time to work on a landscape plan for planting trees and shrubs, and shop for supplies.
  • September is a huge month for renovating or establishing a cool-season lawn like fescue. Sow grass seeds if you need to or fertilize a lawn that is doing well.
  • It’s a perfect time to shop for and add fall-blooming perennials such as chrysanthemums, asters, goldenrod, perennial sunflowers or sedums.
  • Add a fresh layer of mulch to perennial beds, fruit trees and berries.
  • Divide, transplant and label perennials; provide plenty of water to new transplants.
  • Plan spring bulb gardens and purchase bulbs this month in preparation for planting spring flower bulbs in October or November.
  • Dig caladiums and other tender bulbs and tubers and store for next year’s use.
  • Fill outdoor containers with cool-season annuals and ornamental vegetables.
  • For color in the garden fall through spring, add late-season annuals like pansies and violas, snapdragons, sweet alyssum, ornamental kale and cabbage to the garden.
  • Continue to plant cool-season vegetables.
  • Sow green manure cover crops (crimson and white clover, hairy vetch and annual rye) over your vegetable garden.
  • Clean up garden debris and add it to the compost pile; water and aerate the pile to speed decomposition.
  • Add organic matter such as manure, compost and/or leaf mold to improve garden soils.
  • Bring houseplants back indoors before frost and inspect for insects.
  • Continue to take garden notes and/or photographs

Designated as the official botanical garden for the State of Tennessee, the UT Gardens includes plant collections located in Knoxville, Jackson and Crossville. As part of the University of Tennessee Institute of Agriculture, the gardens’ mission is to foster appreciation, education and stewardship of plants through garden displays, educational programs and research trials. The gardens are open during all seasons and free to the public. For more information see


Dr. Susan Hamilton,

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