My soil has always been infested heavily with nematodes and the sandier it is the worse the RKN problems will be so building up the soil with some organic matter will help some but it will not stop them. Mulching heavily also delays the nematodes somewhat. Grafted plants is how I have mostly solved the problem but even they will eventually sometimes end up with some nematode damage but their tolerance is a big help most of the time.
Before I started grafting I had two problems with both fusarium wilt and nematodes. I frequently lost a lot of my plants to one or both. I did find that some varieties resisted the RKN better than others. Of the yellows I used to grow both KBX and Dr. Wyches were the best and sometimes lived the whole season. I found Neves Azorean Red to be more resistant than most others but also had some luck with Arkansas Traveler, Stump of the World, 1884, Brandywine Cowlick's, Indian Stripe and Spudakee. If you can get some Big Beefs they are decent tasting hybrids that have some tolerance to RKN and they do well in the heat also.
Bill
|