Organic Methods for Controlling Colorado Potato Beetle

The Colorado potato beetle, Leptinotarsa decemlineata, is by far the biggest pest for both back yard and commercial potato growers. They are prodigious breeders, with the female Colorado potato beetle laying up to 25 eggs at a time. These eggs hatch, and the larvae do the majority of the damage while satisfying their voracious appetites. They can be difficult to get rid of, since they have adapted a resistance to the vast majority of controls (both conventional and organic) that have been used against them. Your best weapons for dealing with potato beetle? Vigilance and speed.

There are a few methods that work well against potato beetle. They all require the gardener to pay close attention to what is happening in the garden, and to act quickly, as soon as evidence of beetles is discovered. Try any or all of the following:

• Apply neem oil as needed.
• Hand pick beetles, larvae, and eggs and throw them in a bucket of soapy water to kill them.
• Use a vacuum to remove beetles, larvae, and eggs. There are special "bug vacs" for garden use, but honestly, a handheld "Duster Buster" type vacuum also works well.

There are several things you can do to protect your crop from Colorado potato beetles. It's best to use a few of them together, especially if you've had a problem with potato beetles in the past.

• Crop Rotation

  Don't grow potatoes in the same spot year after year. Since the adults overwinter in the soil of the previous years' potato patch, all you're doing if you plant in the same spot again next year is giving the adults convenient access to your plants. They'll pick a potato plant, find a mate, and go about laying eggs. If they're going to try to devour your crop, at least make them work for it a little!

• Floating Row Covers

  Place floating row covers over the top of your potato plants, and leave it. The special fabric will allow air and light through, but will also foil hungry potato beetles.

• Companion Planting

  There are several plants that will deter potato beetle, and it's a good idea to plant at least one or two of them alongside (or even interplanted with) your potatoes. Try planting catnip, tansy, or sage.

• Mulch with Straw.

  Mulching heavily with straw not only helps keep the tubers out of the sunlight, but also creates a habitat for predators of Colorado potato beetle: namely, ground beetles, lady bugs, and green lacewings.

• Plant Resistant Early Varieties

  Certain varieties of potatoes, such as Russet Burbank, have proven to be resistant to potato beetles. Another good practice is to plant early varieties, since potato beetle damage only gets worse as the season goes on (and all of those eggs hatch!) Consider planting 'Caribe,' 'Norland,' or 'Yukon Gold.'