Nematoads

A: Nematodes are small, usually microscopic worms that are in all soils.  Most are beneficial because they help in decomposing organic matter such as leaf debris.  But some nematodes feed on plant roots, causing stunted plants and sometimes plant death.  Once you have root feeding nematodes in your soil, they can be difficult to control. There are currently no chemical pesticides available for the homeowner to use against nematodes. 

If you have not done it yet, call your local county extension agent and ask if they can evaluate whether you have nematodes.  They will ask you to bring in a sample of soil with the roots of one or two plants in the infected area.  They can verify whether you have destructive nematodes. 

The four methods used to manage nematodes are crop rotation when growing vegetables, fallowing, planting a crop of french marigolds, and soil solarization. 

If you are planting vegetables, plant only those that are resistant to nematodes.  These varieties will have the letters "VFN" behind the cultivar name.  Rotate these crops with other non-resistant crops.   You can also plant half of your garden in french marigolds each year and then the other half in vegetables, switching back and forth every other year. 

Fallowing means keeping the soil free of any plants for a growing season.  Till it up every two weeks to keep it dry and free of any growing plants.  This will prevent the nematodes from feeding and their numbers will be greatly reduced.

To solarize the soil, wet it down and then cover it with clear plastic.  Keep the plastic in place for two to three months in the hottest part of the summer.  The heat will kill the nematodes.

The University of Georgia has a good site with information on controlling nematodes at http://pubs.caes.uga.edu/caespubs/pubcd/l209-w.html
The University of California has an excellent site with additional information at http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7489.html

Well, that should do it. Maybe more than you wanted to know. Good luck Janie.
Joe