Bean Beetles Win (this time...)

Ever since we started our market garden seven years ago green beans have been problematic. And for the past two years it's been almost impossible to grow them. Our main problem has been the Mexican Bean beetle (Epilachna varivestis). They reproduce fast, the hibernate in the ground, and they have no natural predators. The adult beetles themselves are not the problem; their larvae is. Those little yellow things are voracious and can decimate a crop overnight. Our strategy has been hand-picking the adult beetles as soon as we notice their presence. We hope we can keep them from laying their eggs on the underside of the leaves. But this technique has simply not worked for us. We are putting too many hours hand picking the critters and, when we add the fact that green beans are already labor-intensive at harvest time, we simply have a crop that we can't grow commercially this year (sorry you won't see green beans in your CSA boxes). One option is to spray Pyrethrin, an organic-approved bio-pesticide that works on bean beetles but, quite frankly, I'd rather no spray other than compost tea. So, next year, we are adopting a biological strategy and will bring in some parasitic wasps (Pediobius foveolatus), which we can buy from a lab as larvae ready to hatch. These fellas, in turn, will feed on the Mexican Bean beetle larvae and, hopefully will reduce their population to manageable levels. Hurray for biology! So, the prospect of having an abundant crop of green beans next year, officially becomes reason number 1 to renew your CSA with us. For now, though, we let the bean beetles have it.