To create a truly and happily sustainable garden is to follow nature’s example of a ‘mix and match’ which, in fact is not as random as many people consider it to be.
Nature has evolved some incredibly close relationships between plants: much as it links every single tree in a forest — recently scientifically proven to be true — via an intricate network of below-ground mycelia (fungal networks), trees are not only interlinked but actively communicate and share things such as water and carbon. Thus, nature has developed helpfully positive relations between plants.
Take something as simple and well-known as ‘tagetes’ or French marigolds, for example. These exude a certain fragrance and natural chemical compounds that greatly assist in keeping certain pests and diseases away from tomatoes, for instance, whilst the lovely herb borage brings phosphorous up into its leaves from below ground and then droops these leaves to feed tomato plants with one of the main nutrients needed to encourage them to flourish and fruit.
Companion planting uses one species’ advantages to help nourish another, creating a natural harmony in your garden
Such a relationship between tagetes/French marigolds, tomatoes and borage is just one of many examples of plants helping other plants to survive and multiply without the need for any artificial inputs — read noxious chemicals — at all.
Known as ‘companion planting’, this natural system has nothing at all to do with planting anything in regimental straight rows at certain distances apart, and everything to do with replicating the selectively mixed clumps and masses of healthy plants observed thriving in wild conditions.
Companion planting is a fascinating subject which, unfortunately, we don’t have space to go into in depth here. But, to get you hooked, here are some well-known examples of which plants are beneficial to each other’s health and wellbeing.
As mentioned above, tomatoes relish the company of tagetes, French marigolds and borage but they like basil and capsicums too. They do not, however, like to be anywhere close to aniseed, so do keep that in mind.
Beans, of all kinds, are sociable plants and thoroughly enjoy being surrounded by beetroot, celery, sweetcorn, cauliflower, French marigolds, nasturtiums, potatoes, strawberries and cucumbers. But they are not at all impressed by any member of the onion family.
Fruit trees, of all kinds, have a love affair with borage as do strawberries and bush fruits.
Cabbage, broccoli, calabrese, kale and cauliflower enjoy the company of fragrant herbs such as sage, thyme, wormwood, mint, basil and dill but really dislike the pungent aroma of mustard plants.
Rose bushes and carrots love onions, garlic and chives as these help keep aphids and other bugs away and, while you may not want to surround your rose bushes with carrots, some clumps of garlic and chives around their roots will certainly not go amiss.
Onions help keep carrot flies at bay while carrots also like being close to lettuce, peas, sage, rosemary and tomatoes — but onions do not like competition from dill.
Swiss chard/leaf beet likes radishes as their neighbour, lettuce and mint, while coriander like radish, carrots and aniseed.
Sweetcorn loves sunflowers, potatoes, peas, beans, pumpkins, squash, melons, cucumbers and both ‘tagetes’ and French marigolds. But cucumbers do not like potatoes, so keep them well apart.
Aubergines are happy with beans and okra, and garlic with peas and beans.
Lettuce hates celery but adores strawberries and radish.
Turnips like peas and beans as do pumpkins and squash.
Mint dislikes chamomile but loves jasmine and nasturtiums and melons are not at all happy anywhere near potatoes and neither are pumpkins and squash.
‘Calendulas’, nasturtiums, tagetes and French marigolds are delighted with any kind of company, and are loved by all and sundry for the hard work of keeping general pests at bay yet encouraging pollinators — and they brighten up the entire garden in the process.
If you find companion planting confusing — it does take time to learn all of the many recommendations — or if you wish to apply the method to plant varieties not mentioned here, an internet search of the subject will throw up lots and lots of useful combinations and information.
If you are still confused, then keep a note of what is thriving in your garden and the company it is keeping. Slowly, over the months and years, you can construct your own personal companion planting guide entirely based on what works for you in your garden and in your localised climatic and soil conditions.
Some of the results may well confound the experts, and think of the endless hours of fun you will have in the process!
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Published in Dawn, EOS, May 19th, 2019