Inviting Friends to the Garden: Or Organic Pest Control 101

A Gardener's Friend: The garden spider.

A Gardener’s Friend: The Black and Yellow Argiope, or common garden spider.

The farming season is in full swing, which means most of our energy these days is going into hoeing, planting, pest control and very soon now, harvesting.

By FAR the worst job is Pest Control. Actually, it’s the only bad job in the garden. Planting, harvesting, even hoeing have satisfying rhythms to them that invite reflection, listening, paying attention and being astonished.

But Pest Control adds a whole other dimension to farming that I rightly distain. Mostly because the critters pestering me want to live, and happen to like veggies as much as I do, in fact, need veggies to live. Cabbage maggots, for instance, have no other dietary options except the roots of cole crops like broccoli, kale, and cabbage.

I’ve lamented before that farming is a rather violent enterprise. We kill plants we don’t want (and we call them “weeds”), and insects we don’t want (and call them “pests”). It uncomfortably reminds me of other ways we create categories of “us” and “them” to justify actions that benefit us at the expense of them. But I’ll set that aside for now.

At least one advantage to growing organically is that we only kill herbivores. In the garden we actually like the carnivores that feed on the herbivores. Lady bugs, Lacewing, spiders, ground beetles, hunting and parasitic wasps (especially mini-wasps), predatory bugs… these and more are farmers’ friends in the garden. If we used pesticides we would wipe these out as well as the aphids, cucumber beetles, flea beetles and various caterpillars.

A few quick lessons in organic pest control.

1) Learn which insects are your friends and which are not. Here is a great picture guide of beneficial insects and here is one for the top 10 “pests”.

Cabbage maggot

Cabbage maggot

2. Part of learning which insects are problematic is learning how to diagnose what pest is causing whatever you are seeing in your garden. If spring broccoli or cabbage plants that looked robust yesterday all the sudden start wilting and eventually die, you likely have cabbage maggots eating their roots. If leaves are being eaten in chunks, suspect slugs (or birds and rabbits for that matter). If leaves are getting lots of little tiny round scars or holes, you might have flea beetles. If healthy leaves are becoming all lacey-looking, suspect cucumber beetles or caterpillars. Most of the time you’ll easily see the bugs doing the damage. Since cabbage maggots eat roots and live in the dirt, they are more difficult to see. Look through a trowel full of dirt under a kale plant that has just died and you’ll find them if they are present.

3) Consider temporary floating row covers until your plants are established. These are light-weight fabric that allows air, water, and most of the light through. In addition to keeping a bunch of pests out, they also keep crops warmer and extend the growing season on both ends. Use them until plants are well established, and remove them as blossoms emerge.

4) Plant a variety of flowers in and around your vegetables that attract beneficial insects. The goal is to keep inviting insects looking for pollen and nectar to the food in your vegetable patch since many of them are eager to add leaf-eating insects to their diet. We planted marigolds, zinnia, nasturnium and sunflowers in our fields amongst the vegetables, and have honeysuckle that borders one field and flashes like a “Visitors Welcome” beacon. Besides, flowers add beauty and interest. Who wouldn’t love seeing a few sunflowers towering above bean plants?

5) Keep your soil healthy by rotating the vegetables in your garden.

6) Finally, be prepared to hand-pick off cucumber beetles, slugs, and various caterpillars. I had to reconcile myself to the slaughter of hundreds, probably several thousand cucumber beetles last summer as I scooted through the zucchini and summer squash patch smashing copulating pairs (I hoped their last moments were enjoyable) and single beetles looking for a hook-up. The infestation was so bad that we brought out the shop vac to speed up the process. Before adding our Hazelnut Patch this year, which is working well, but not perfectly, we hand-picked lots of slugs off our lettuce and green cabbage. The small slugs made for wonderful treats for chickens, as would any of these “pests”. In fact, if we could train our chickens to only eat pests and not also the lettuce and broccoli (and to hold their poop until they were back in their yards) they’d be a wonderful aid in pest management!

Pesticides are easier. But I wouldn’t want to eat plants saturated in what kills other living things, or give them to anyone else to eat. An increasing volume of medical research is suggesting the mass use of pesticides that started in the 1940s and 1950s was One Bad Idea. Nor do I like the idea of killing a bunch of beneficial insects that pollinate strawberries, squash, beans, peas, cucumbers, melons… That has contributed to other problems, like the disappearance of and collapse of honeybee colonies in the United States.

As an aside, this helps explain why organic vegetables generally cost more than conventionally raised ones. It takes a lot of human labor to control “pests.” As I said, using pesticides is an easier option. And pest control doesn’t take into consideration that hand hoeing weeds also takes a lot more time than spraying with herbicides… which is a conversation for another day.

So here’s to making friends with some pretty cool insects that would enjoy an invitation to come feast in your garden!

 

 

2 Comments

  • Good advice! Thanks Lisa! I didn’t know that zinnias were good for beneficial insects!

    • Yes–I imagine a lot of fragrant blooming flowers draw insects! But its a good idea to note flowers as we walk around that seem to particularly attract bees and other pollinators. We fill our landscape with them–on purpose and accidentally!

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