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September Gardening Tips

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Landscaping Tips

  • The days are getting noticeable shorter. We have lost about an hour of light in the morning and the evening. During September plants begin the slow process of hardening down for winter. Photosynthesis slows down and plant roots are storing strength for the winter.
  • If you plan to put mulch or bark down this is the last month to do it. You don’t want to trick your plants into a false bloom or a growth spurt. The mulch or bark keeps the roots warmer signaling the plant that its time to reverse the dormancy slide.
  • Visit nurseries to pick out plants with fall color.
  • Your heather should be trimmed after flowering and prune out dogwood twigs affected by anthracnose (this is where branch ends are dead) being careful to use correct pruning techniques that are available in any good pruning book. Dogwood pruning cuts are slow to heal and quite hard on the tree. Don't do much pruning at this time of the year. It promotes new growth that won't be hardened down for the winter and will most likely die if we have below freezing weather.
  • Rake diseased leaves away from the tree as they fall and dispose of in your trash. Do not compost or recycle them.
  • Bring houseplants inside, later in the month, spraying them off before you do and check for hidden insects. Slugs breed now so keep after them.
  • Plant or divide peonies and other perennials for next spring's bloom.
  • Keep your dahlias picked for continual bloom.
  • Continue watering all your plants and lawn if rain is scarce. You should also attend to your lawn by aerating, thatching and reseeding if needed. Also early in the month is a good time to fertilize your grass. You will need to continue to mow your grass weekly in September. In October you can look forward to once every 10 days. You can choose and plant new ground covers where you had poor grass or a lot of weed growth. There are a number of beautiful new ground covers that are available.
  • You should begin to plant cool-season annuals and refrigerate or store your spring bulbs in a cool dry area.
  • Add lime to soil now so it can decrease soil acidity during the winter. This can substantially limit the moss growth in your lawn areas. Lime does not kill moss but it raises the pH of the soil so the grass does better and the moss does poorer.

Vegetable Garden

Cover your tomatoes and peppers to keep warmth in for longer production. Tomatoes can produce into November if covered and the leaves are protected from getting wet and too cold. Sow seed for fall salads and cooked greens like spinach and chard. Plant over-wintering onions, mustard, radishes, and turnips. Plant cover crops like crimson clover.

Child's Garden

Gather as many colors and shapes of leaves as you can find and press them in your telephone book or leaf press. Help pick tomatoes and squash. Rake up leaves for compost and for winter mulch. If you’re going to mulch your leaves mix them with grass cuttings. They will mulch better and give you a better carbon to nitrogen ratio for better and faster mulching.