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Companion planting
Companion planting is the practice of growing different plants together for a range of benefits.

This article looks at the role of companion planting and how certain combinations of plants can help improve the health and growth of your fruit and vegetable crops.

With our beds already dug over or mulched, now is the time of the year when we begin to sow our first seeds. However before you start filling up your vegetable bed with wild abandon, it's worth taking a moment to consider where your fruit and vegetables may be best planted and what benefits can be achieved by placing other plants next to them, helping them reach their full potential. Planning your vegetable bed can help ensure you have a more productive garden.

The practice of companion planting can be dated back to the ‘three sisters’ planting plan devised by Native Americans. This worked by having squash, beans and sweetcorn all planted in the same bed. The squash would cover the ground and prevent weed growth; the beans would feed the soil with extra nitrogen to promote better growth for other plants; and the sweetcorn gave the beans a structure to climb up. Although this particular method of growing is harder to achieve than it sounds, we can still use the basic rules of companion planting in our own garden to achieve better results for our crops.

It is worth noting that whilst companion planting has not been scientifically proven, it offers tried and tested rules of planting which can work to protect and strengthen our crops.

  • Companion planting is an environmentally friendly way of gardening as it removes the need for chemical sprays that may otherwise do damage to wildlife visiting your garden
  • Some of the plants used to attract or ward off pests can brighten up your fruit and vegetable beds and work well planted as a border surrounding the plants within it
  • While it may feel tiresome initially to have to concisely plan where all your fruit and vegetables will grow best, companion planting along with practices such as crop rotation can further our understanding of the plants we work with
  • Horticulture is a broad subject and companion planting offers another point of interest – whether it be for someone who wants to have as much knowledge as possible available to them whilst planting their vegetables or someone who may be physically less capable and can be more involved in the exercise on a cognitive level
  • Onions are known to repel carrot root fly. It’s advisable to plant four or five rows of onions to each row of carrots and not to plant too closely together so as not to hinder the carrots’ growth
  • Marigolds bring some welcome colour to your vegetable beds and ward off aphids and white fly
  • Tansy not only wards off ants as well as other pests but encourages ladybirds and honeybees. Be mindful of its toxic nature and that it can cause allergies to flare up in some people
  • Mint, oregano, parsley and thyme can also drive away aphids with their strong smells and can be planted in pots or along rows with other vegetables. Be wary of the mint spreading out of control
Companion planting herbs
  • Nasturtiums act as a sacrificial crop that draws pests, such as slugs and cabbage white butterflies away from your cabbages and other brassicas. Not only do nasturtiums keep your crops unmunched, you can also add the flowers to a salad and use the leaves to make a peppery pesto
  • Basil works in a similar way to nasturtiums but on a smaller scale. It can be used in a greenhouse to draw potential whitefly away from your early growing cucumbers and tomatoes
  • Nasturtiums, thyme, oregano, rosemary, basil and cosmos work to attract pollinators, such as bees and butterflies, to your vegetable plot. Make sure you give them sufficient time to flower
  • Poached egg plants will draw pollinators to your soft fruit plants such as raspberries and blackberries when planted around their base
  • Sweet peas will encourage insects towards your climbing beans if they are planted in amongst them and provide you with a fuller crop later in the year
  • Yarrow will also attract ladybirds
Companion planting nasturiums
  • Beans, peas, lupins and generally anything from the pea family will release nitrogen into the soil and therefore be of benefit, particularly to those in the fruit family. You can either grow these plants alongside each other or rotate where you plant your fruit and beans from year to year. You can also cut the stalk and leave the roots from the bean plants in the ground after the plant has died back so as to get as much of the nutrients they provide into the soil as possible
  • Yarrow is also meant to enrich the soil around it. Be careful that it does not spread and take over the bed too much over a couple of growing seasons
  • Basil has been noted to improve the flavour of plants it is planted next to including tomatoes, aubergines and lettuce

Tomatoes planted next to carrots result in the nutrient hungry tomatoes taking many of the nutrients away from the carrots next to them. This then leads to the carrot root reaching further down into the soil, resulting in a better crop. This also breaks up the soil for its neighbouring tomato, meaning its roots can grow fuller and result in more tomatoes.

While you should be wary of taller growing plants taking sunlight away from their shorter neighbours, in the case of pumpkin and sweetcorn, these two plants will benefit from the same amount of light as they begin to grow and in time the partial shade the sweetcorn provides will be of benefit to the pumpkin as it matures. This partial shade can also prevent lettuce and spinach bolting earlier than you want them to.

If this is a subject that whets your appetite to know more, you can look further into it online and find many diagrams that demonstrate where best to place your peas and what may tarnish your tomatoes.

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