Borage and pot marigold attract pollinators. (Contributed)

Borage and pot marigold attract pollinators. (Contributed)

Gardening: Companion planting for 2018

Make better choices and informed planting so harvests more abundant.

I thought I would start the new year by encouraging all of us to work with nature in 2018 – and there is no better way than with companion planting.

I know that some gardeners believe it to be nothing more than a gimmick to sell books such as Carrots Love Tomatoes or Roses Love Garlic (both written by Louise Riotte), but we now have a lot of scientific proof verifying the benefits of pairing plants.

In the simplest of terms, it works by one of several means: providing additional pollen or nectar to attract pollinators and increase yields; drawing pests away from the desired vegetable through trap cropping; physically shielding crops from wind or excessive sun (not every plant likes full sun); providing nutrients by means of nitrogen fixing; or even by simply repelling unwanted pests or animals.

There is one more category that includes allelopathic plants, or those that have developed and release natural toxins to inhibit the growth of adjacent species.

In the realm of edibles, a few common examples of these would include black walnut (toxic to tomatoes, peppers, potatoes and other members of the nightshade family), black elderberry (Sambucus nigra) and fennel, although the latter will attract beneficial insects and pollinators.

So your best bet with this class of plants is to give them their own growing space away from the vegetable garden. A few choices that fall in the repelling category include rosemary and thyme (repels cabbage moth), sage (repels carrot rust fly), asparagus (repels harmful nematodes), yarrow and chives (repels aphids) and cilantro (repels potato beetle) – keeping in mind that the repellent quality is not an impervious barrier.

As far as fixing nitrogen is concerned, all beans (broad, soya, scarlet runner, bush and pole) and peas (green, snap, snow) will do the trick, although that does not always make them the best companion for every vegetable, so do a little research before designing your planting scheme.

Local organic vegetable grower Zdena Novy was kind enough to share some of her favourite pairings, these include potatoes-horseradish (with the latter planted to the side), onions-cabbage, carrots-leeks, spinach-strawberries (keeping in mind that the strawberries are perennial), broccoli-beets and the classic garlic-tomatoes.

For a more detailed list of companion plants for local conditions with numerous options, just type West Coast Seeds and companion planting into your web search.

Perhaps the most important category here are those plants which attract pollinators, as our wild bees are finding fewer native plants to forage and their domestic cousins are suffering from colony collapse disorder – a devastating phenomenon resulting from numerous factors, including pesticides (75 per cent of all honey worldwide is contaminated with neonicotinoids), mites and malnutrition.

So as gardeners, we really need to attract the few pollinators available to our plots to provide pollen transfer and fruit development.

Ordinary summer flowers, such as sweet alyssum (which has an added benefit of a low profile), calendula or pot marigold, sunflowers, nasturtium (also a good trap crop for aphids), cosmos and German chamomile will all draw bees and other pollinators.

Perennials, which work along the same lines, include candytuft (for early crops), bee balm, scabiosa, black-eyed Susan, purple coneflower and agastache with its abundant blooms and licorice-scented foliage.

So let’s make 2018 a year of better choices and informed planting so that our harvests are more abundant and our use of pesticides (even organic-based) is kept to a minimum.

By choosing better varieties and giving them optional conditions, you too can earn those bragging rights that all of us as gardeners need from time to time.

Mike Lascelle is a local nursery manager and gardening author