Who doesn’t like being around a friend? Around someone with similar likes perhaps? Or in whose company we bloom to our fullest or even someone who offsets our own quirks?

Well, as it turns out this may be a natural instinct for all living things, including plants. Maybe we’ve learnt this behaviour from plants? Watch them grow in the forest and you find they thrive in the company of some and are unable to in the presence of others. It is interesting to understand how this works and use it to the advantage of all plants in your organic garden.

Many of us think of organic gardening as growing without the use of pesticides. While this is a key feature, an organic garden is much more than a mere shift from harmful chemical fertilisers to organic ones. It is in fact an entire interconnected system that includes insects, birds, sun, water and all other aspects of a living community. Viewed through such a lens, companion planting is a core element of organic gardening.

Its benefits are many – natural insect repellents, shade and windbreaks; providing necessary nutrients to the soil and other plants and reducing the need for external fertilisers. Another advantage of companion planting is making optimal use of available space by growing plants of differing heights. By growing different types of plants, the garden becomes a conducive environment for beneficial microbes and insects.

In addition to the science of companion plants having the ability to improve the yield of surrounding plants, some people have also found that companion plants improve the flavour of neighbouring plants; a strong connect with our taste buds! For instance basil planted with tomatoes not only improves the yield – they taste good together!

The planting of the ‘Three Sisters’ (beans, corn and squash) by the Native Americans is often cited as a classic example of companion planting: The beans provide the essential amino acids, riboflavin, and niacin; the squash provides vitamins A and C, and vegetable fat from their seeds; and the corn provides all the other nutrients needed.

It is said that each of the ‘Three Sisters’ when grown together provided a harvest that would keep and sustain the community for months. In terms of space, the tall, sun-loving corn proved to be the perfect companion to shade tolerant squash and the creeper beans used the corn as a trellis. This diverse canopy also helped in pest control to a fair extent. What also worked was that these vegetables tasted good together, when cooked!

When selecting companion plants for the garden, not only should we consider which pests are deterred but also what each plant adds or takes away from the soil, and what effect the proximity of strong herbs may have on the flavour of neighbouring vegetables!
Some underlying techniques of companion planting include:

• Mix up monocrops. If you want to grow a lot of one vegetable (eg tomato), plant several pots/ containers of it in the garden and mix it with another vegetable/ flower in each of them.
• Interplant herbs and flowers. By planting flowers and herbs among your vegetables, we can attract beneficial insects and birds, which are natural predators to those pests that might otherwise eat up our plants. Attractive flowers and fragrant herbs often confuse pests and deter them from finding our preferred plant!

Some examples of companion planting in your vegetable garden

Beans: All beans enrich the soil with nitrogen fixed from the air. Generally, they are good company for carrot, celery, corn, eggplant, peas, potato, beets, radish, and cucumber. Beans are great for heavy nitrogen users like corn because beans fix nitrogen from the air into the soil so the nitrogen used up by the corn are replaced at the end of the season when the bean plants die. Keep beans away from the alliums (flowers).

Basil: Planted with tomato improves growth and flavour. Basil is also said to repel flies and mosquitoes.

Carrot: whose friends are peas, onion and tomato. One drawback with tomato and carrot when planted together: tomato plants can stunt the growth of the carrots but the latter will still be retain a good flavour. Keep dill away from carrot.

Cucumber: Cucumber is good to plant with corn and beans.

The three plants like the same conditions: warmth, rich soil and plenty of moisture. Let the cucumbers grow up and over the corn plants. A great duet is to plant cucumber with sunflower. The sunflower provides a strong support for the vines. Cucumber also does well with peas, beetroot, radish, and carrot. Radish is a good deterrent against cucumber beetles. Dill planted with cucumbers helps by attracting beneficial predators. Keep potato away from cucumber.

Lettuce: Does well with beet, bush bean, pole bean, cabbage, carrot, cucumber, onion, and radish. It grows happily in the shade under young sunflowers.

Potato: The following may be planted with potato: bush bean, cabbage, carrot, celery, corn, Tomato: can be grown with cabbage, onion, radish, garlic and carrot. Tomato protects asparagus from asparagus beetles while asparagus protects tomato from nematodes. Don’t grow potato and tomato with each other; potato inhibits tomato growth while tomato renders potato more susceptible to blight.

Other tips

Use mulch of mint leaves around brassicas like cabbage.
Grow shallow rooted onions among deep rooted carrots.
Compost beet leaves – they are a good source of magnesium.

Keep yourself in touch with what others in Bangalore are growing and learning at https://www.facebook.com/groups/OrganicTerraceGardening/

Further Reading:
http://obsigarden.wordpress.com/2007/10/23/companion-planting-and-natural-pest-control/
http://www.seedsofchange.com/enewsletter/issue_55/companion_planting.aspx
Carrots love Tomatoes – Louise Riotte⊕