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How to Apply Beneficial Nematodes

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Nematodes are microscopic organisms found in the soil that can do harm or good in your garden, depending on the kind. Some nematodes are already in your soil, but most of these are usually the harmful kind that hurt the roots of trees or plants. Beneficial nematodes are meant to help by killing other pests, such as lawn grubs. You can buy them in packages at garden centers.

Open the packets of nematodes and pour them in a watering can or garden sprayer. Add enough packets to cover the area you want to spray. The packet will tell you how much space it will treat.

Pour water into the container. The amount is not important, simply fill the container up. Stir the water to mix in the nematodes.

Spray or sprinkle the nematodes and water over the space where you want them applied.

Water the lawn after you are done applying the nematodes. Use a sprinkler to moisten the soil down to a depth of at least 2 inches.

Nematodes Bad For A Yard?

Plant-parasitic nematodes affect all parts of plants, but the greatest numbers concentrate on the root systems. Root symptoms caused by nematodes include galls, brown-black lesions and swollen and discolored root tips that restrict further growth. You can solarize your garden in fall by preparing the soil like you normally would, then smoothing it out evenly. Spread a sheet of 1 to 2 mil clear plastic on the surface and leave it for for four to six weeks. This will heat the soil sufficiently to destroy many nematodes, as well as some soil-borne fungi and bacteria. Heterorhabditis bacteriophora is a nematode that actively hunts for prey, seeking out the larvae of black turfgrass ataenius and fiery skippers as well as white grubs. The nematode you've chosen should be applied when you know the pest insect is active, often throughout the spring and summer, although white grubs may be more active in the early fall.

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