Asked November 10, 2016, 1:11 PM EST

Wanting to give nematodes a try in the garden. Can you point me in a good direction for where to purchase them, and when to apply? I was hoping to purchase locally rather than on-line. My main pest issue has been cucumber beetles.

Lane County Oregon nematodes

2 Responses

Beneficial nematodes are perishable and don't have a long shelf life so might be difficult to find locally. Your best bet is to check with your local well-stocked garden center. Depending on the time of year, they may have the nematodes in stock. Otherwise, they can order for you.
A word of caution about using nematodes for managing cucumber beetles: There is limited scientific research in this area. There have been studies done, but typically these are limited to controlled environments (like testing in a laboratory or a greenhouse setting, but not out in the field or garden exposed to the natural environment.)
Take some time to read the packaging: There are many different types of beneficial nematodes available to purchase and not all nematodes work against all pests. Some of the types that have been at least lab tested against cucumber beetle are: Steinernema sp. and Heterorhabditis sp.
Keep in mind that these beneficial nematodes only affect the soil-dwelling portion of the cucumber beetles life. The nematodes won't affect the adults that cause the aboveground foliage damage-only the immature larva in the soil. So timing of application of the nematodes is important. Click for more information on the cucumber beetle life cycle and management options.
And the last caution: the damaging-causing adult beetles are very mobile. So just because you are diligent in managing them in your own garden-it doesn't mean they won't just fly in from neighboring yards!
Good luck and thanks for using Ask An Expert!

Thank you. The link you provided about the life cycle of the Cucumber Beetle was very helpful. Learned a little more about them from it. I am surrounded by grass fields, so sounds like the nematodes wouldn't be worth the expense. I'll try some of the other trapping/netting ideas.... the battle goes on!