While I have already mentioned on this blog that I believe the dirty word of the summer is leaf blight, I also think that Squash Vine Borer, Mexican Bean Beetle, Colorado Potato beetle, Japanese beetle (you get the idea) also make the list. For gardeners, it can seem like the summer entails a never ending battle against garden pests and problems – deer, rabbits, moles, insects, diseases, weeds, etc. Most experienced gardeners have a plan for dealing with these issues, and unfortunately most of these plans involve some pretty toxic chemicals. The majority of gardens I see use some organic principles and some conventional methods. This is one reason that the Grow Appalachia project is so wonderful. Through Grow Appalachia we are able to share organic alternatives with experienced gardeners and start new gardeners off with organic principles. While some people are skeptical about organic gardening, almost everyone is willing to try new methods.
This week we held our Organic Garden Maintenance and pest control workshop. The workshop covered ways to deal with many common garden pests, but I am just going to share with you a little bit about how to deal with my arch nemesis: the squash vine borer. I had never encountered this guy until two years ago, and during the past two gardening seasons he has completely won the battle between him and my garden. I have not tried any of the control methods listed below in past seasons, but I am this year. Several families took old row covers from us during the workshop to try covering some young squash and cucumber plants with. We will see how it goes (hopefully well)!
Adult squash borer moths look like a wasp with an orange abdomen with black spots. These pests lay flat, brown eggs at the base of squash plant stems. Most gardeners do not realize that they have a borer problem until it is too late to save their plants. The larvae overwinter in the soil and emerge in the spring. The adults lay eggs at the base of the squash vine. The larvae burrow into the squash stem after hatching and move toward the base. The invaded plant will wilt and die. Begin monitoring plants in mid-June and stay vigilant through August in Kentucky.
|Borer and frass at entry point into stem|
|Adult squash vine borer moths|
Cultural Control Methods:
- To prevent moths from laying eggs on the base of the stem, young plants can be covered with a row cover. Covers need to be placed tightly around plants to keep moths from getting under them. Make sure that you are not trapping other insects under the cloth! These covers will need to be removed to allow for pollination once plants bloom.
- Another way to prevent moths from laying eggs on the base of the stem is to wrap strips of row cover around the stem. Add more wrapping as the vine grows.
- If you notice saw dust like frass (bug excrement) on the stem, this will be where the larva entered the stem. Slit the stem with a knife lengthwise and remove larvae. Immediately cover the vine with soil.
- Remove infested squash vines immediately and destroy in order to prevent larvae from completing their life cycle.
- Remove all old boards and crop debris from garden area at the end of the season to prevent larva from overwintering in the garden area
Organic (OMRI approved) insecticides:
- Insecticides are pretty ineffective against the vine borer, but a few specific methods can be used
o Spray the vine weekly with insecticidal soap or Bt OR wipe the vine every five days with a damp cloth to wipe off eggs
o Safer Brand Garden Dust (Bt) OR Green Light® Bt Worm Killer 2 OR Monterey Bt easy to mix liquid concentrate
Another common garden pest is deer. My family always built a fishing line fence around the sweet corn field by wrapping high strength fishing line around posts on the perimeter of the garden. The theory is that when a deer runs into the fishing line, they cannot see what they ran into and so they will not try to jump over something that they cannot see. One of our Grow Appalachia families has been using this system for the past two years, and they say that it works perfectly!
|Sonny Maggard's fishing line fence|