IPM stands for integrated pest management. It’s a method of managing–not totally destroying–pests, diseases, and weeds in the most sustainable way while still promoting maximum plant health. To practitioners of IPM, identification is key–identification of the plant species and the pest–and proper management often means monitoring carefully but otherwise doing nothing at all.
Consider, for example, my vegetable plot:
From bottom to top, you see some marigolds and nasturtiums, bean seedlings, two squash plants, four eggplant plants (and quite a few weeds that I pulled but left on the ground to break down). If you look carefully, you’ll see that the eggplants look somewhat pale and spindly, especially in contrast to the very sturdy squash plants (all were planted at the same time). The eggplants have been heavily afflicted with flea beetles. I could spray pesticides, but that is ruled out for two reasons: I won’t use pesticides, and ours is an organic garden that doesn’t allow them. I could spray with neem oil soap or use bT in the soil, both recommended organic remedies. Or I can simply monitor carefully. On close inspection, I can see that the plants are making new leaves that are unaffected by the flea beetles and that look healthy and green. I also read that flea beetle infestations are usually worse in spring than later in the growing season. So for now, I’ll continue to monitor the plants, but I’ll do nothing.
The marigolds and nasturtiums are there because they’re old fashioned organic remedies: they’re supposed to discourage particular pests. I don’t know if that’s really true, but other gardeners say they work, and they’re pretty and harmless, so why not?
Last year our garden was heavily infested with squash vine borers. Most of the summer squash plants were affected–I lost three out of four. This year, I am practicing an old-fashioned remedy: every few days, I rub down the stems of the squash plants with my fingers. That’s supposed to remove the eggs of the borers before they hatch, so the caterpillars never enter the stems and do their damage. We’ll see.
The other end of my little vegetable patch is less afflicted at the moment:
Here are healthy bush bean plants in flower, extremely healthy turnips, carrots, and beets that desperately need thinning (we’ve been eating the young greens in salads, so I’ve been reluctant to pull up the plants), and pea vines full of skinny, unripe pods. There’s also a tomato in front that’s just been tied to its stake for the first time–it’s about 2 feet tall.
Notice the yogurt container tucked among the plants. That’s my highly scientific rain gauge. If I’m not sure whether to water, I check the level of water in the container. If there’s an inch or more, there’s no need to water the garden. Last week I emptied the full container twice.