Friday, September 10, 2010

September Horticulture Tips

  • Fall is an excellent time to try to control tough lawn weeds such as creeping Charley (ground ivy), violets, speedwell and black medic. Quack grass, bindweed and other perennial weeds in the garden may be treated with products such as Roundup once all vegetables have been harvested.
  • In the lawn, creeping Charley and other perennial broadleaf weeds (not quack grass or crabgrass) are best controlled this time of year. During the cool fall days, these perennial weeds are actively growing and will readily absorb herbicides. Use one labeled for "Difficult to Control Broadleaf Weeds" for best results. Products such as Tri-Mec and Weed-B-Gone in the purple label seem to work best when applied about the first week of October.
  • The apple harvest is underway. Visit one of our local orchards to enjoy some fresh fruit and cider. 
  • Plan to transplant deciduous trees and shrubs later this month or in October. Fall is a great time to transplant things. The weather is cool and there is usually a good level of moisture. Also, most perennial plants like to add new roots as the soil temperature drops. 
  • Move houseplants back inside prior to the first signs of frost. Many of them are tropical and will not tolerate temperatures in the low 40's. Check pots for unwanted insect passengers and weeds. 
  • Smooth skinned caterpillars called orange striped oak worms may be eating oak leaves this month. They are not gypsy moth caterpillars. The webs at the tips of branches of many trees are called the fall webworm. They seem to be more abundant some years than others and this is a banner year for them. Since it is so late in the season, they will generally do little harm. Treat them only if they are in large numbers on small landscape trees. 
  • In the vegetable garden, remove stems, roots and leaves of plants that were infested by insect or disease. Many of these problems over‑winter on the debris and will reappear next spring if left on the site. 
  • Check the lawn for grubs. Cut a small square of sod and look at the root zone of the grass. Five or more grubs per square foot indicate the need for control measures. Use a soil insecticide labeled for grub control and be sure to water it into the soil immediately after application. Generally about a half an inch of water is needed to move it down to where the grubs are feeding. This is NOT the correct time to apply products containing Merit (which is the active ingredient called imidocloprid) for grub control. Those products work best when applied in late June or early July. 
  • Decorative gourds should be washed with a weak chlorine bleach solution (one part bleach to 9 parts water) before storing. This kills surface molds which might rot the gourds later. To store winter squash, dip them in a weak bleach solution and let them cure in a warm, dry area for a week or two. Then, place them in a dark, well-ventilated room at 45 to 60 degrees F. Avoid stacking squash if possible. Spread them out to allow for air circulation and to minimize the spread of rot. Inspect them monthly through the storage period.
Written by Ralph Heiden
Originally printed in September/October 2009 Connections