Your Entire Property

  • Save wood ashes from your fireplace or firepit and add them to your compost.  They contain phosphorous, potassium, and calcium.


  • If your lawn needs it, transition from a summer to fall fertilizer.  We recommend a slow release organic fertilizer such as Espoma’s Organic Lawn Food – Fall Winterizer.  (Can be applied from September to November.)

  • Fall is a good time to control certain perennial broadleaf weeds in the lawn.  Herbicides applied now are drawn into the plants roots as the plant prepares for winter.

  • Fall is a great time to plant lawn seed (when temperatures are around 75 degrees and falling).  Fescue germinates at soil temperatures of 50 – 65 degrees (daytime temperatures typically from 60 to 75 degrees).  Germination occurs in 10-14 days.

  • It can be helpful to aerate soil before spreading seed.

  • Once seed is spread, keep the soil moist until grass is established.

  • Check in with us here at Kennedy’s to establish the best schedule for fertilizing, (re-)seeding, and weed control.

Trees and Shrubs

  • Select accent plants for your landscape that will provide autumn color.  Trees that have red fall color are flowering dogwood, red maple, sugar maple, red oak, and scarlet oak.  Shrubs with red fall foliage include sumac, viburnum, and blueberry bushes.

  • Think about adding nut trees. They can accent the house, provide shade in the summer, and even become a food source.

  • Transplant early spring flowering trees and shrubs now.  If you wait until spring, you may sacrifice a season of blooming.  Wait until early spring before you fertilize fall transplants.

  • Water newly planted trees and shrubs to provide sufficient moisture and prevent winter damage. Add a three inch layer of bark mulch around the base of plants to retain soil moisture and regulate soil temperature.  Do not allow mulch to pile up around the base of the tree trunk.  Wait until early spring before you fertilize trees and shrubs planted in the fall.

  • Limit pruning to removing diseased, damaged, or broken stems and branches.  Late pruning may stimulate new growth that will not have enough time to harden off before winter.

  • Remove pesky seedlings of woody plants such as elm, oak, or maple.  If left too long they will take over gardens and other landscape plantings.

  • Rake up leaves, twigs, and fruit from crabapple and other fruiting trees and dispose of them in the trash to help control disease and overwintering insects.

Perennial Beds, Bulb Plants, Roses, etc.

  • Divide and transplant (as needed) spring-flowering plants such as astilbe, peonies, phlox, bleeding heart, iris, and Oriental poppies after they bloom.  Do this as needed, typically every four to five years.  Prune back top growth as needed by up to one third.

  • Divide day lilies, usually every few years for best bloom.

  • Divide and transplant no later than early fall so the roots have time to get established before the cold weather arrives.  Plants that are transplanted too late in the fall might get heaved out of the ground with a hard frost.

  • There is no way to transplant a plant without incurring some root damage.  To reduce stress on transplants, divide and transplant on overcast or rainy days.  Apply three to four inches of mulch around the base of transplants and water well.  Check on the plant every few days; if the top few inches of soil are dry, water again.  Be careful not to overwater.

  • Make notes also of those late-blooming plants you want to divide in the spring and where you want to transplant them to.  These notes will come in handy next March!

  • Do not apply any more fertilizer; allow plants to finish the summer growth cycle in a normal manner.  Heavy applications of fertilizer or excessive pruning at this time will delay your plants’ dormancy process that has already begun in anticipation of winter.  New growth can be injured by an early freeze.

  • Plant daffodil, crocus, hyacinth, and tulip bulbs in late September or early October giving them time to establish roots before the soil freezes.

Annuals – Containers and Beds

  • Switch out containers; plant them up with mums, cabbages, and other cold-tolerant flowering annuals and ornamental vegetables to last through Thanksgiving.

Houseplants and Tropicals

  • Do not wait for frost warnings to move your prized plants indoors.  Temperatures of 45 degrees F or lower can damage many tropical house plants.  Bring tropicals and houseplants back inside when temperatures begin to drop.

  • Before bringing tropicals and houseplants back inside for the winter, wash off leaves with a hose.  Apply two applications of insecticide before bringing inside.  We’d be happy to answer any questions you might have concerning treatment options.

Vegetables and Fruits

  • Plant a fall crop to get the most out of your garden.  Cool season crops include lettuce, spinach, arugula and other greens, and beets, carrots, potatoes and other root crops.  You could also try for a second crop of peas.

  • If you are done with your garden for the season, remove all spent plants to reduce breeding grounds for insects and disease.  Consider sowing a winter cover crop that will reduce erosion, fix nitrogen in the soil, and add organic matter and nutrients when you till it into the soil later.

  • Make a note of any particularly productive or unsatisfactory varieties of vegetables that you planted this year.  Such information can be very useful when planning next years’ garden.

7 responses to “September Yard & Gardening Tips”

  1. JOYCE FARRELL says:

    The list above is very helpful and inspires new ideas. Kudos to you all to take the time to put together such helpful information. I have what I call a Kennedy’s yard because so much of my landscaping came from Kennedy’s.

  2. Dr. Diana Perry says:

    So helpful!
    Thank you so much!

  3. John Covell says:

    I had about a 5 foot evergreen tree that died. We want to replace it with a bee and butterfly friendly tree or shrub about the same size. Recommendations? THX JC 781-383-0178

    • The Kennedy Team says:

      Hi John,
      I have passed your request on to our Nursery manager, Susan.
      She will be in touch. You are also always welcome to stop in and talk to anyone in the nursery.
      They are all very knowledgeable!

  4. Charles Higginson says:

    Thank you for your fall garden tips. My question is how to repair dead grass sections of our lawn. Most of the lawn has greened up nicely, but there are patches of dead grass that do not show any signs of recovering. Should I rake these patches up and reseed or wait a while longer? If wait, how long before I prepare to reseed. Realizing that water restrictions are still in effect. Charles Higginson

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