Growing ‘good companions’

NAIROBI: In a garden, certain plants have been found to make good companions, drawing mutual benefits from one another. The process is known as companion planting, which is basically planting different vegetables, herbs, flowers and fruits in close proximity.
The best way to illustrate the idea behind companion planting is to take a look at what has come to be known as the three sisters: corn, beans and pumpkins. The three mutually benefit from one another in an interesting symbiotic relationship.

Corn provides support for the climbing beans. Beans, like other legumes, have bacteria living on their roots that help them absorb nitrogen from the air and convert it into a form that the other plants, especially corn, can use. The large, prickly pumpkin leaves act as mulch. They shade the soil, suppressing weed growth and deterring animal pests.
Similarly, certain vegetables, herbs and flowers make great companions in the garden. Here are a few you should consider next time you want to tweak your planting plan:

Vegetables

Planting vegetables with other beneficial plants has been found to improve the health and even the flavour of the vegetable. Instead of resorting to chemical control of pests, planting vegetables alongside beneficial plants can do the job just as well.

Separating rows of cabbages with rows of onions has been found to be a great combination, possibly due to the onion’s strong scent which confuses cabbage pests. Clovers inter-planted with cabbages also reduce the native cabbage aphid and cabbage worm populations by interfering with the colonisation of the pests and increasing the number of predatory ground beetles. Tomatoes like being grown near aromatic herbs such as rosemary and sage. The aromatic plants repel insect pests that may be detrimental to the tomato. Tomatoes, on the other hand, have been found to deter caterpillars for the herbs.

Herbs

Many other herbs are beneficial to a number of edible and ornamental plants. Lavender is a general insect-repellent and makes an excellent small hedge. It is a great addition to the garden, attracting bees and numerous white and blue butterflies, which apart from looking pretty, also help with pollinating fruit-producing plants.

Fruit-producing plants in turn attract birds into the garden. The birds eat many pests, such as aphids, caterpillars and various flies. Similarly, garlic is perfect next to roses and cabbages as it helps keep away aphids and cabbage butterflies. It has been found to accumulate sulphur, a naturally occurring fungicide, which helps in the garden with disease prevention.

Flowers

Certain flowers and flowering herbs offer potential benefits for a variety of vegetables. This not only improves the health of your vegetable garden, it also adds colour and beauty. Marigolds are cited as a wonder drug by many organic gardeners and the bright flowers make a colourful companion plant for any part of the garden.

They deter many pests, and seem to spur growth in roses. They are also said to reduce the number of lawn nematodes, while attracting hoverflies and their larvae, which in turn eat aphids. What’s more? Marigolds can be planted alongside virtually any other plants in the garden. Other flowers that have benefits for the garden include geraniums, petunias and sunflowers.

—The writer is a landscape architect.