Last week we talked about Cabbage Lopers, Cabbage Moths and Flea Beetles and how to control them organically. This week we have a few more pesky pests to combat in the garden!
Mexican Bean Beetles
If you haven’t met Mexican Bean Beetles before, you will soon if you grow any kind of pole or bush bean. These little distruct-Os are ruthless destroyers of all that is good in your bean patch. The first indication you have them are the yellow eggs laid underneath the leaf surface. Bright yellow larvae soon emerge and are easily squashed or removed due to their color. Larvae quickly eat the leaves leaving behind a lacy pattern of damage. Other options include covering your bean crop with a lightweight row cover to keep adult beetles from being attracted to it and laying more eggs. Planting early season beans can help avoid peak populations but if your beans are already planted, then what? Handpick (we put adults and larvae in a bucket of soapy water), use floating row cover to prevent egg deposition, attract insect predators with interspersed flowers and herbs, or release predators like the spined soldier bug or parasitic wasps. A last resort is to spray with neem or pyrethrin weekly, although I have found that this solution rarely is a panacea when a population is so large it warrants spraying. In future years be sure to rotate your bean crop.
Do you have any weirdly shaped holes on your plants that seem to have no rhyme or reason? These are likely from slugs. They tend to be big holes with no real shape or pattern. These guys come out at night and feast. Beer in pans does attract some to their happy demise or copper will repel them. Garden purveyors often offer many uniquely designed copper tools to repel slugs, lining your garden beds with copper for instance or putting a copper barrier around each seedling. Expensive anyone? I think so. We mulch heavily for water conservation and weed control so slugs are a part of the game. You can handpick (our slugs go to the chickens) or trap in beer or on cabbage leaves or potatoes, THEN feed them to chickens. Iron phosphate is OMRI listed, but there is some controversy about its use in organic gardening. Another barrier option is to make wide barriers of wood ash or diatomaceous earth around seedlings.
These probably must be addressed here because they are everywhere and they are so sneaky. You think the plant looks great but this one leaf curls oddly and BAM, there they are in enormous numbers. As goes with all of these insects, promoting a diverse garden with beneficial plants to attract insects that will predate (=EAT) these buggers is the most important part of gardening organically. Ladybugs will eat some aphids but it might not easily solve your problem. A heavy stream of water can do the trick of dislodging the guests. Insecticidal soap can help keep them at bay. The best thing I’ve used was a homemade garlic and cayenne solution to keep them away. Finally, plants that have too much nitrogen or are over fertilized (even organically) will be ripe targets for aphids. You want the plants to be healthy but not with overly succulent foliage. Finally, the last resort is spraying neem or pyrethrin.