Fundamentals of Companion Planting
Companion planting is growing a variety of vegetable plants, herbs, and flowers in the same area to influence a healthier, more productive garden. Planting certain plants close to each other can create support for the plants, utilize space and soil nutrients more efficiently, help prevent pests and disease, and create a habitat for beneficial insects.
Companion Planting Can “Lend a Hand”
By planting certain plants together, they can give each other the physical support they may need. Corn or sunflowers are both plants that grow with tall, strong stalks. These are great for supporting beans or cucumbers. Another example of a plant that can help another is to plant a row of corn on the south side of your lettuce. The corn will give the lettuce shade from the summer heat—shade that the lettuce needs, allowing you to harvest the lettuce longer.
Better Use of Space and Nutrients
You can use your space and soil nutrients more efficiently using companion plantings, especially if you have a limited area in which to grow. For example, after your spring crop of radishes and spinach has finished in July, get your bed ready for your fall planting of cabbages by adding in manure and compost. Place out your cabbage transplants; then in September or October plant your garlic bulbs around the cabbage. The cabbage will be harvested in the early winter, leaving nutrients and space for the garlic to grow in late winter and early spring.
Blanching is a technique of mounding soil or other materials around the base of a plant to prevent the light from reaching it. This practice makes the stalk whitish in color like, for example, celery or leeks. The lighter color is often more preferable when selling these products.
Another example is to plant your basil around the base of your tomato plant, just making sure that your tomato plant will be supported so enough light will reach the basil. The basil and tomato plants like the same growing conditions, have similar water requirements, and are good companion plants. Or, plant your celery and leeks near each other; they both have similar growing requirements and grow best when blanched. These are just some examples of ways companion planting will maximize a small-space garden and help you use time efficiently.
Helps to Prevent Pests
Planting a diverse range of plants in your garden can mask or hide a crop from certain pests. The diversity is one way companion planting seems to work. Insects can be repelled or attracted by the odor of certain veggies, herbs, or flowers. Knowledge about particular plants can be used to draw a certain pest to one plant (the sacrificial plant) rather than to another. Planting mustard greens near your cabbage, for instance, will attract the flea beetle to the mustard rather than the cabbage plant. Planting onions or chives in your carrot bed will help to prevent carrot fly from reaching the carrot root. Dill will attract aphids rather than having them get into your broccoli heads. These are just some examples of how one plant can be beneficial to another if they are grown near each other.
Attract Beneficial Insects
Creating a habitat and providing food for beneficial insects is another principle of companion planting. The tansy flower is a great example, as ladybugs love this flower. The ladybug is your garden friend, so using plants to attract or keep it in your garden is one of the best ways to prevent unwanted insects like aphids. Ladybugs feed heavily on aphids. Rather than immediately pulling spent plants, letting some of your veggie plants go to flower is an easy way of attracting insects and birds to your garden. They will be attracted by the smell and food that is available in these flowers.
Companion planting is one of the oldest traditions when it comes to planting a garden. Historical records show the ancient Romans utilized a variety of plants in their garden designs to prevent pests. The Native Americans grew what is known as the “three sisters.” Corn, beans, and squash were planted together to save on space and prevent pests, and because they supported each other while growing (the corn stalks supported the beans and squash to grow vertically). Many gardeners swear by companion planting; however, since there is no scientific proof that growing certain plants together makes for healthier ones, there are some people who dismiss companion planting as an old wives' tale. Give some of these suggestions a try in your own garden and make your own case for the benefits of companion planting.
When planting a diverse garden with a variety of vegetables, herbs, and flowers, it is important to label your plants (especially when young) so you remember where things are planted. Another important tip: make sure your pathways are obvious so no plants will be trod on accidentally.