In nature we can observe plants growing together, mutually helping each other to grow strong and healthy. In the same way, we can replicate this in our garden, be it in the ground or in pots. We can grow plants together that will help each other take up nutrients, improve pest management or attract pollinators. For example, basil grown near garden crops such as tomatoes and lettuce will improve their flavour and also repel mosquitoes. Potatoes and marigolds repel Mexican bean beetles and therefore plants grown alongside them will have natural pest control. Traditionally gardeners have been planting garlic with their roses since they repel rose pests. Certain varieties of marigold can control the nematodes that attack the roots of melon. Some plants act as a pest trap and thereby protect their companion, for example, aphids love nasturtiums and will flock to them instead of their companion plant. By planting these with a crop such as tomato, our tomatoes will be protected. So, in this way we can grow healthy disease free plants without resorting to chemicals. Aromatic herbs act as natural insect repellents. They confuse insects with their strong odours that mask the scent of the intended host.
Companion planting can help utilise all our available space to its full potential, this is particularly useful in the terrace garden where we are limited for space. More than one plant can be grown in the same pot. For example, tall plants can provide shade for sun sensitive shorter plants. Plants that love to stay near the ground, such as vines, can be coupled with tall plants that like to reach for the sky, thus using the available space to the maximum.
Benefits of companion planting
Shade regulation: Large plants provide shade for smaller plants that need protection from the sun.
Natural supports: Tall plants like corn and sunflowers can be a support for sprawling crops such as cucumbers and peas.
Improved plant health: When one plant absorbs certain substances from the soil, it may change the biochemistry of the soil in a way to help another absorb those that it needs.
Healthy soil: Some crops such as beans and peas help to make nitrogen available. Similarly, plants with long taproots bring up nutrients from deep in the soil, thereby enriching the top soil for plants with shallow roots.
Weed suppression: Planting sprawling crops like potatoes with upright plants minimizes the open areas that can be occupied by weeds. However sometimes certain weeds can help pull nutrients from deep in the soil to the surface and when they decompose the nutrients become available for shallow rooted plants.
Below is a table of plants that can be grown together
One of the keys to successful companion planting is observation. Experiment with planting different crops together and record the results of your endeavours. There are some plants that do not do well together, such as when beans and peas are planted with garlic and onions, the beans and peas show stunted growth. With such a huge variety of plants to choose from, companion planting is surely the way forward to a healthier, abundant garden.