September Garden To Do List

“In the garden, Autumn is, indeed the crowning glory of the year, bringing us the fruition of months of thought and care and toil. And at no season, safe perhaps in Daffodil time, do we get such superb colour effects as from August to November.”
– Rose G. Kingsley, The Autumn Garden, 1905

In my mid-South garden fall is a slow transformation into winter.  The heat may not break until late September with the first frost occurring at the end of November.  I no longer think of fall as a time to put the garden away, but rather the season for reaping all that I’ve sown during spring and summer.  The colors are so saturated and there is such a bounty of fruits, flowers and vegetables.  As I write this I feel a twinge of betrayal, but I’ve come to love autumn even more than spring.

  • Start a compost bin. A circle of woven wire fence is a simple way to contain leaves and garden debris. Fill the bin with alternating layers of leaves and green plant material, like grass clippings. Avoid adding sticks, diseased plant material, and weeds. Lightly water and turn about once a week. After the blend decomposes into dark, fertile organic matter, add it to your flower and vegetable beds to enrich the soil.
  • Keep treating roses, lilacs and phlox for powdery mildew.
  • If you didn’t get all your seeds sown this summer, save some for next year. Store left over seeds in a labeled, airtight baggie or glass jar in a cool, dry location. You’ll have better luck if you keep them indoors rather than a garage or tool shed.
  • Build a cold frame to extend the growing season.
  • Begin holding back on water and fertilizer on Christmas cactus until buds appear.
  • Move your houseplants indoors before the first hard frost. The best time to make the move is when inside temperatures are similar to those outdoors. Wash the leaves with a diluted mixture of mild soap and water. This will help your plants breathe and respond better to light. Then to eliminate any pests they may have picked up during the summer, treat with an insecticidal soap.
  • Early fall is the best time to sow many types of wildflower seeds. The key to success is to make sure that your plants have enough time to germinate and establish themselves before the first hard frost. That’s usually about 8 weeks.
  • Sow arugula seeds. Sprinkle the seeds in narrow furrows that are 5 inches apart and cover with 1/4 to 1/2 inch of soil. Keep the soil evenly moist and the seeds will germinate in about 10 days. The plants are ready to harvest in 5 weeks when the leaves are about 4 to 6 inches tall and just beginning to form lobes.
  • Stake tall growing autumn blooms such as salvia, dahlias and chrysanthemums.
  • Gather green tomatoes before the first killing frost. Wrap them in paper and store at 60 to 65 degrees F.
  • If you live in a region where winter temperatures typically drop below 20 degrees F for extended periods, you will need to lift and store tender bulbs such as elephant ears, dahlias and calla lilies after the first frost.
  • Freeze corn on the cob to use in soups and casseroles this winter. To freeze sweet corn simply leave the husks on and cut an inch or so off the tip of the ear then slide the corn into plastic bags to store in the freezer.
  • Selective applications of herbicides on perennial weeds are especially effective during the fall while the weeds are storing nutrients in their roots for winter.
  • If you live in an area that is colder than zone 7 (0 to 10 degrees F in winter) move your banana trees indoors before the first frost.
  • Root crops such as carrots, radishes and potatoes may be left in the ground well into winter. Mulch heavily and harvest as needed.
  • Add well-rotted manure and organic humus to your flowerbeds. Your plants will thank you for it next spring.

Good to Know

I garden in zone 7b.  Spring usually starts in March and fall extends through November.  The summers are long and hot.  I write these tips with the idea that they are applicable to all zones during a general period of time. However, given microclimates and weather extremes timing can vary.  Observe the conditions in your garden and apply them accordingly.