Yes, all of the above should be of some help. However, I occasionally remind people of a simple, effective treatment learned many years ago. As a furrow/planting hole is made to plant beans, carrots, parsnips, tomatoes, etc. (either young plants or seeds) toss in handfuls of regular granulated sugar and plant as usual. For those with large gardens 40# bags of dried molasses can be substituted for granulated sugar. Available where horse feed is sold. This year we are trialing a dry molasses mix that has dried kale added. This is all that was available here. So far all plantings are healthy and repelling the RKN. For plants that take a bit of time to mature it would be wise to scratch in a sugar top dressing halfway through the growing season. There is still time in your zone to grow some other crops. Give this sugar method a try.

Jo, Like Larry, I've never seen any quantifiable independent research that shows neem oil applied to soil has any effect on nematodes, although I have seen such claims made by those who benefit from selling neem. I would never apply neem to soil because it likely would kill some of the good microbes in the soil which then would leave your soil less healthy. Remember that healthy soil is full of all kinds of biologically active creatures, which I tend to lump together in a group and call "microbes". What are these microbes and how many are there? The microorganisms include all sorts of microscopic plants and animals, including nematodes (there are beneficial ones, you know), fungi, actinomycetes, bacteria, yeast, germs, protozoa and algae. Healthy soil that has a good compost/humus content is believed to have as many as 50 billion microbes in 1 tablespoon of soil, according to organic gardening expert and author J. Howard Garrett, aka 'The Dirt Doctor'. Since all the microbes in soil play an important role in soil health, you don't want to put anything in the soil that would hurt those microbes. I'll use spider mites as an example of the unintended consequences of using a 'cide' to kill the bad pests and inadvertently killing beneficial insects too. While spider mites are a pest in certain circumstances, there are beneficial predatory mites that help keep the spider mites under control. When you spray a miticide on plants infested with spider mites, you kill not only some of the spider mites (most pesticides do not kill 100% of the pests) but also the predatory mites that help keep the number of spider mites down. When the mite population rebounds (and it always does), the pesky herbivore spider mites bounce back first because they feed on plants and plants are readily available so they have an endless food source. Then, in a much more slow manner, the predatory mite population, which are carnivores, rebounds. The problem is that beneficial insects rebound very slowly because the 'mamas' don't reproduce until there's already a good food source for their babies to eat. So, while the mama predatory mites are waiting for the food source to increase to the level they need, the spider mite population is growing very rapidly and getting out of control. Once the predatory mite population begins to surge and feed upon the spider mites, the spider mites have a huge head start and your plants are severely damaged. I think if you used neem in soil, you'd likely kill off a good portion of the microbes in the soil, leaving your soil less healthy, less fertile and more vulnerable to soil-borne pests, including root knot nematodes and various soil-borne diseases. So, even if the idea of trying neem is attractive, it could hurt more than it might help. I used the spider mite example to illustrate how using a 'cide' for pest control can backfire because it is the story of my life. My dad was a terrific gardener, but he fought spider mites my entire childhood, and he lost that battle in late July or so of every year, and so did his best gardening buddy, Mr. Camp. I watched the two of them try everything to kill those spider mites, but the spider mites always outlived and outlasted their efforts. So, I grew up thinking that no matter what you did, you would lose your tomato plants to spider mites in July. Eventually I grew up and had a home of my own and my own garden. During our second year in our house, we decided we wouldn't 'poison' our tomato plants with the miticide commonly sold to home gardeners back then. A miticide didn't help the first year in our new home when we did use it, so it seemed pointless to spend money buying it and then spend time spraying it on the plants the second year. What happened? Our spider mites didn't get out of control and our tomato plants didn't die. Once I convinced my dad to give up miticides, he never lost his tomato plants to spider mites again. Still, it probably was another dozen years or so before I finally understood why not using a miticide saved our plants from the mites, and that's because I didn't know back then that there was such a thing as predatory mites. So, I hope that tale illustrates the dangers of even attempting to use a soil treatment to kill the root knot nematodes. Even if it would kill the nematodes (which I highly doubt), it would kill all the other microbial life in the soil. As an organic gardener that is absolutely the last thing you need. Even worse, what I think most likely is the neem oil would kill the good microbes, but not the root knot nematodes. When I am trying to figure out what to use in my garden or landscape, I fall back on that old adage used by physicians.... "first, do no harm". You might have a chance of killing some of the root knot nematodes by applying beneficial nematodes to the soil. The most important factor affecting the efficacy of beneficial nematodes would be to apply them at precisely the exact temperature they need, and also to use the right beneficial nematodes. Dawn

Sick some root knot nematode eating nematodes on them. Worked for me a few years back. These guys get Fungus knats and other nasties too. Here is a link that might be useful: Data for Steinernema feltiae

The primary problem I had was rhizoctonia root rot. It's contagious. That didn't show up in the first plant I sent to the Texas A&M plant diagnostic labratory, because I had bleached it. (Bleach in a 10% solution is sometimes used on roots.) So, the only thing they saw was the root knot nematodes. When I sent in a second specimen, they diagnosed it and gave me some suggestions for treating it. When that didn't work, I called the county agent. He said that rhizoctonia is not very treatable and I would probably lose most of my hosta. I did. So, the nematodes weren't that big a problem in my situation, it was the fungus. You will note though, the beach solution did not kill the nematodes. They spread in water, so if the infected plant has been there a while, they've probably already spread. Not all plants are equally susceptible. About 10% of my hosta survived. The usual treatment for nematodes is heat. On commercial farmers fields, they bring in these heat/steam treatments and treat a whole field. Hosta are susceptible to foliar nematodes. the usual treatment for those is dig up and trash the plant and then pour boiling water in the hole. One place I would go for advice is the facebook page on hosta diseases. I'm not sure she still does, but Carol Brashear used to moderate that page. She and her partner are very active in hostadom (they do the hostalibrary.org), so that might be a good resource. That's about all I can tell you. All the other information I have and the resources I used are detailed above. But again, the nematodes weren't my big problem. bkay