Sunday, March 15, 2009

Companion Planting

Companion planting is a great way to integrate organic pest control into your gardens. Growing certain plant combinations help deter pests and attract beneficial insects, and some things when grown together improve the taste of both. It helps the soil recover from depletion and presents a more diverse (and to me) attractive garden.
Companion planting is a very old practice, with some citing it to Roman times, but is best known in cottage garden style gardens. Some plants are used as "traps" or sacrificial plants, as caterpillars and other pests will prefer them rather than your vegetables. Nasturiums are used in this way. Nasturiums are pretty and edible, but may not be as important as your vegetables so you would plant them around the more important crops.
Marigolds, or calendula, are one of the best flowers for companion planting, as they deter nematodes. I plant them with all my vegetables. They must be the French or Mexican variety. The one I use is the Mexican Crackerjack, sometimes known as African marigolds, although they are actually native to the Americas. These have large orange and yellow flowers blooming in Fall, which are pretty and make nice cut flowers as well. Tansies, petunia and geraniums are other good flowers to deter insect pests. To attract honeybees, try Orange cosmos. I can't say enough about this flower! It's gorgeous, blooms all season, and my bees slept in it every night! I grew it along with my tomatoes and cucumbers.
Many herbs when grown with vegetables will improve the flavor, increase essential oil production and attract beneficial insects such as hoverflies, lacewings, assassin bugs, ladybugs and wasps. Tomato and basil is one such combination. Borage is a general cure all and has beautiful sky blue flowers. Onions are said to be good with roses and rosemary repels cabbage fly so is good with anything in the brassica family. I'll include some links to tables on the web. There are quite a few combinations! Most gardeners have heard of the "Three Sisters" method of planting used by Native Americans. This method grew corn, beans and squash together, as well as sunflowers around the borders. Lemon balm is good to have around the garden here and there as it deters many insects, smells great and makes a lovely tea.
Other plants improve the soil. Beans and peas are nitrogen fixers, as are clover and alfalfa. If you rotate your crops, this is a good way to help the soil recover from what the previous year's planting has depleted. However, you also have to take into consideration plants that have a negative effect on other plants. Fennel is a favorite of my monarch caterpillars, but it stunts the growth of most vegetables so it is best planted in the butterfly garden. Walnut trees secrete a chemical substance called jugone that prevents other plants from growing near it, as do chestnuts and hackberries. This is nature's version of chemical warfare to eliminate the competition. These are called allelopaths and I think they're very cool. :) Try explaining them to a child to spice up the world of plants for him or her!
Here are a few links to lists of companion plants:

I hope this helps! I'm slowly getting this blog going, but I hope to add a lot to it. Comments and suggestions would be appreciated!

1 comment:

  1. Beautiful pictures of your garden and such wonderful info. I located your blog through Vintage Village. Happy Gardening!