Spring is Coming... How Early Can You Apply Nematodes?

As winter winds down, many of us are looking forward to more time spent outside. A common question we get in late winter and early spring is "when can I apply beneficial nematodes?" Beneficial nematodes are a great, all-natural control for a variety of common pest insects. But, since nematodes are living organisms, care needs to be taken to ensure they stay living and viable. As a general rule, beneficial nematodes can be applied as soon as the soil is no longer frozen.

It is true that freezing nematode products will kill the nematodes, but once established in the soil, nematodes are able to survive much colder temperatures than they can out of the soil. We do advise waiting a day or two to apply if you are expecting a hard frost. But in general, once you apply the nematodes it is not a problem for them if the weather takes a turn and temperatures drop. In fact, the nematodes can travel quite a ways vertically and will go deeper into the soil to survive.

There are some instances where early spring may not be the ideal time to treat, but that usually has more to do with the specific pests being targeted and their life cycle. See When to apply for more. However, for the majority of pests, early spring is a great time to apply beneficial nematode products as a first line of defense.

Happy gardening!