Neem may help control nematodes, one of the most damaging pests in the world, according to a report published in the journal Environmental Science and Pollution Research. Nearly invisible, they eat the roots of crops, stunting growth, minimizing production and eventually killing the plant. This study of neem and nematodes from South Korea takes a look at the use of the leaf in an alcoholic – rather than water – extract. It reports that an undiluted neem leaf extract killed 100% of nematode eggs. The impact was definitely driven by the concentration of neem in the product used. It’s also interesting that they selected leaf (easy to grow almost anywhere in the U.S.) vs. the oil that can only be produced in tropical regions. The oil contains much high levels of the compounds traditionally used to treat insects, including nematodes.
Soil Drenches Work on Multiple Insects
In our “yarden,” we grow neem trees underplanted with food for homeless people distributed through the Sustainable Living Project. We use diluted NimBioSys neem oil as a soil drench on plants like cucumbers, pumpkins and squash. They get cucumber beetles that lay eggs inside their stems where they’re impossible to reach with a spray. The neem oil soil drench also has been highly effective on the papaya fruit flies that destroy fruit from the inside out just before they ripen.
We also grow a ton of tomatoes — a nematode favorite — including the Everglade tomato that blooms and grows for months. I always carefully check the roots for signs of nematodes when we finally pull them (they bloom themselves out) and haven’t seen any so far. Scientifically speaking, I can’t say if it’s the extra-tough species of tomato or the neem controlling the nematodes but it’s very encouraging to see plants with no damage in Florida.
Unpublished photographs from Georgia Organic Solutions point toward the neem, however. Plants on farms treated with neem oil in drip irrigation system show no damage from nematodes while other nearby plants are clearly infested.
This document is intended for education only and is based on research posted online at the National Institutes of Health website. It has not been evaluated by the U.S. Food and Drug Administration or the Environmental Protection Agency. Neem Tree Farms does not sell products which are intended to diagnose, prevent, treat or control any disease in human beings, or to kill or repel pests except as those allowed by the EPA in its registration of NimBioSys.