I deal with a fair share of pests in the garden, a valiant battle against rodents, worms and the like. I’d come to a place where I felt that my understanding of these foes and subsequent method of dealing with them was becoming like second nature. Now all of that is ABOVE ground. This week I have been humbled, to put it mildly, by the forces of mother nature that I essentially can never fully control. I’ll just get to the point. Root Knot Nematodes.
I know that every season differs and crops can alter from year to year depending on the conditions and weather. But this year things have been WAAAAY different than last. My indeterminate (produces long season yields) tomatoes produced one crop and then died. ALL of my pumpkins grew with vigor and then all baby pumpkins yellowed and fell off (and the leaves). My green bean plants yellowed already and stopped producing. The cantaloupe vines suddenly stopped growing. We’re not even at the end of August! It’s been a sad, sad state. 99% of all vegetables are susceptible to root knot nematodes. Total bummer.
When I pulled up some of my plants, I noticed round, nodule-like growths all over the root systems of these poor veggies. Not good, I thought. Not at all. The internet ushered in the bad news. Root knot nematodes are microscopic, eel-like roundworms that live and feed around plant roots. The knots that they form on the roots effects the water and nutrient conducting abilities of the roots, causing plants to grow more slowly and weaker, dying off quickly with smaller crops of edibles. Management is difficult. Of course.
The best site I’ve found in my research on identification and management is through UC Davis. Go if you have these pests in your garden!
Today I covered the effected area with thin, clear plastic sheeting that will remain there for 6 weeks, aka solarization. Yup. There goes my fall plantings for half of my plots. The idea is that you heat the upper two feet of soil in the hottest months of the year under this sheeting, which in turn kills the nematodes and also weed seeds (an added bonus). It’s not a guarantee, but it’s the best organic alternative according to multiple reliable sources.
** Make sure you bury the perimeter of the plastic in a trench under the dirt. Deeply water the level area before covering, as this will help heat the soil. The key is to pull the sheeting taught so that it’s as close to the dirt as possible to maximize heating. I purchased my plastic at a home improvement store in the paint section. 1 mil thickness is best, as it allows maximum heat without tearing or blowing away.
I will also plant French marigolds among the future veggies, which emits a deadly oil for the little buggers. I could go on and on about this topic, but instead head on over to the above link and do a little reading if you’ve got root knot nematodes like I do. Wish me luck!