As the gardening season begins across North America, gardeners are looking for ways to reduce their environmental footprint. At the same time, however, they want to maintain their yields, and if possible reduce the amount of work they have to do. While working in the garden is definitely enjoyable, or at least satisfying, just being able to sit back and look at the garden is also very rewarding.
Companion planting is a way to fulfill all of these wishes. Companion planting is the practice of planting two or more plants in association with each other, to provide benefits to one or all of the plants involved.
The main benefit of companion planting is to provide chemical-free pest control, though there can often be other benefits as well. Many plants, by virtue of their scent, or the chemicals they produce naturally, repel many pests and insects. Some even act to suppress other plants, though they can be made to be beneficial.
Tall, sun-loving plants can be planted with shorter, shade-tolerant plants, increasing yields for both. This spatial interaction can also provide physical protection for the plants, say if one is thorny or tough, it can keep larger animals away from the primary crop. Planting pumpkins with corn is an example of this technique. North American First Nations people used this technique, far predating European expansion to North America. They called it the Three Sisters, and along with the pumpkins and corn they also planted beans. The corn provided a framework for the bean, the beans provided fertilizer for the other two, and the squash provided protection.
Companions can also provide a hospitable environment for beneficial bugs. Queen Anne’s Lace (wild carrot) can be planted with several different crops, and helps to protect them by attracting several different types of predatory insects, including lacewings and parasitic wasps, which can act to control pests on neighboring plants.
Beans and other legumes can be planted alongside other plants, like corn, spinach, and lettuce, among others. It acts to fix nitrogen in the soil, helping the current crop of plants, but also providing fertilizer for the next crop as well.
Nurse-cropping is a technique where taller or more sturdy plants are used to shield smaller, less hardy plants while they establish themselves. The nurse plants can also be used to crowd out weeds and other competitors.
Trap cropping is another form of companion gardening Certain plants, like petunias and geraniums, act strongly to attract some pest species, sparing crops and plants like roses, tomatoes and peppers from leaf hoppers and Japanese beetles.
Some common companion plantings include:
- Onions help: Peppers, potatoes, tomatoes, cabbages. Aren’t suited for: Beans, peas, parsley. Repels slugs, aphids, carrot fly, cabbage worm
- Basil helps: Peppers, Tomatoes. Increases humidity and flavor
- Marigolds help Most. Repels many pests and perennial weeds
- Borage helps Almost Everything, and repels pests
- Beans fix nitrogen in soil
- Carrots help Tomatoes
- Tarragon helps Everything and repels many pests, enhances flavor
- Chives help Apples, carrots, tomatoes, but aren’t suited for: Beans and peas. They also repel many pests, and help prevent apple scab
Companion planting reduces the costs of gardening, both financial and environmental. A good mix and rotation of crops will provide fertilizer, pesticides, herbicides and enhancements for which there is no artificial substitute. Though some companion plantings require careful tending, overall they reduce maintenance time required in the garden. All it requires is some research and care when planning the garden, and the addition of some extra plants to the typical mix.
For the gardener concerned about pesticides, for someone wishing to grow organic food, companion gardening is their best route. And for everyone else, it is an ideal way to lessen their impact on the earth, while still enjoying the fruits (and vegetables) of her bounty.