Your Own Green Army

By Jenna Mervis

Bugs. They creep. They crawl. They bite. They chomp. They chew, suck, sever, cut and poison. They bring a vegetable garden to its knees, and a vegetable gardener to tears. For several decades the hapless gardener has armed herself with an arsenal of pesticides, waging a Hiroshima-like war on pests. Good and bad bugs are massacred in a hail of pellets and showers of toxic spray. Not a creature is left alive.

But what if there were another way? According to Jane Griffiths, author of Jane’s Delicious Garden, and landscaper Brigid Jackson of Ariston Elemental Garden in Cape Town, there is: Companion planting.

“Companion planting is combining certain herbs, vegetables and flowers that have a beneficial effect on one another,” Jane explains. “Some plants attract beneficial insects such as bees and butterflies. Others repel harmful insects, both above and below ground. Then there are plants that provide food for other plants. Some companions are camouflage plants, such as nasturtium.”

If your garden is a warzone, then it’s time to holster the spray gun and pack away the poison. They may have leaves for fingers and roots for toes, but the following five companion plants will set to work repelling bugs and feeding your pillaged soil. They can be your new green army. All you need to do is get planting. 

African wormwood: artemisia afra

Have you ever encountered thickets of grey-green plants with woody stems and feathered leaves that give off a strong herbal smell when crushed? This is Artemisia afra, or African wormwood, a powerful medicinal plant and indigenous garden guardian.

“I’m totally in love with it,” Brigid smiles. Brigid is the mother-gardener of  Ariston Elemental Garden.Ariston is a small garden and set of allotments sandwiched between a busy main road and railway line in Cape Town. In this city oasis, Brigid has planted a hedge of Artemisia almost as tall as she is. “Feel the ridges of the main stem. An old sangoma taught me that if a plant has a ridged stem it has herbal properties.”

Artemisia’s medicinal properties are quite extensive. It’s used to treat parasites in humans and animals and as a remedy for flu, fevers and bronchial conditions.

For an edible garden, though, Artemisia, like its namesake, Artemis the Greek goddess of hunting, is a formidable and beautiful huntress. Its strong smell acts as a natural insect repellent. This makes it an ideal garden mulch, particularly for strawberries, cauliflower, broccoli and lettuce.

Artemisia is a hardy perennial and loves to be cut back each year in late winter. That said, a large plant can be plucked and trimmed year round. Sprigs placed in vases around the house will keep away mosquitos and flies.

A tip from Jane’s Delicious Garden is to place cut sprigs alongside newly planted seedlings. Not only does this provide shade for young plants, but it will also keep away damaging insects, such as cutworms.

Location: Full sun

Height: Up to 2m

Good Companions: Preferably plant it away from the vegetable garden but near enough to pick leaves.

Yarrow: achillea millefolium

Pliny the Elder wrote in his book, The Natural History, that the Greek warrior Achilles discovered a plant that could heal wounds. Achilles was reported to have used this plant as a wound poultice for his soldiers in battle. Pliny called it Achilleos and millefolium (meaning, a thousand leaves).

A thousand leaves is an apt description for yarrow’s feathery mat of soft, fern-like leaves. But don’t let this softness fool you. In an edible garden, yarrow is both a warrior plant and military doctor. The pungent aroma of its leaves repels harmful insects, while beneficial insects such as ladybugs and predatory wasps are drawn to its delicate flowers.

Yarrow can also improve the quality of your soil. It accumulates essential nutrients, such as potassium, magnesium and calcium, and then returns these to the soil as the leaves decompose. This makes yarrow a powerful plant doctor for all plants growing around it. 

Location: Full sun

Height: 15–20cm

Good Companions: General all-round good companion

Comfrey: symphytum officianale

Deep-rooting comfrey is a tireless nutrient miner and no edible garden should be without it. A healthy soil is a garden’s first line of defence against insect invaders.

Comfrey has also been known historically as “knitbone” for its use in promoting the healing of broken bones, bruises and burns. Just be mindful that this plant is not edible, and can cause rashes on broken skin.

Perhaps comfrey’s most important use is as liquid manure—an easy to make, stinky, garden brew. Deep roots dig beyond the reach of other plants, sucking a range of nutrients into its prickly leaves. A concoction made from comfrey leaves is exceptionally high in potassium, calcium, nitrogen and other nutrients essential for a thriving vegetable garden.

“Comfrey leaves make a really strong plant food,” Brigid explains. “It’s a smelly process but it really works. You soak the leaves in water for a few weeks to a month. Then strain off the leaves, put these on the compost heap, and dilute the liquid 1–10. You can use it as a spray or simply water with it.”

Jane’s tip: set aside a small space for comfrey, or grow it near your compost heap. Use trimmed leaves to line seedling holes before you plant. 

Location: Full sun to semi-shade

Height: 30cm

Marigolds: tagetes

In your edible garden army, the marigold is an undercover agent. Its colourful floral disguise and attractive scent conceals a more sinister purpose. Below the ground, the marigold is a lethal weapon and formidable barrier plant.

“Marigolds repel many harmful insects, including unwanted nematodes in the soil,” Jane explains.

Nematodes are microscopic worms that burrow into the roots of vegetables and lay their eggs, causing blockages and disease. A marigold root exudes a chemical called thiopene that repels these nasty nibblers. 

A mass planting of marigolds will clear a piece of earth of unwanted nematodes, enabling you to plant a fresh and healthy batch of young seedlings in the next planting cycle. Flowers will attract beneficial insects such as bees and hover-flies, rehabilitating the natural cycle in your garden.

The Tagetes family is quite a large family, mostly native to South America. In South Africa, the khakibos weed is also a member of this family. Called Tagetes minuta, khakibos is thought to have been introduced to South Africa during the Anglo-Boer War, via horse feed imported from South America.  

What it lacks in looks, khakibos makes up for in potency. This is one weed you should resist pulling. Plant as a cover crop or use as a companion plant to eliminate all manner of root-eating pests.

Location: Full sun

Height: 15–20cm

Good Companions: Tomatoes, dill, potatoes, beans, cucumbers, eggplant, cabbage, asparagus

Nasturtiums: tropaeolum majus

An all-rounder when it comes to protecting a vegetable garden, the nasturtium is easy to grow, edible and tactically quite clever.

“The nasturtium is a camouflage plant and a trap crop for insects such as aphids,” Jane notes. “This means aphids will prefer the nasturtium and leave your vegetables alone.” Nasturtiums ramble over other plants and their saucer-shaped leaves help to conceal the distinctive shapes of vegetables and confuse enemy insects.

Brigid, too, uses nasturtiums extensively in Ariston’s gardens. “They come up every year, attracting snails and caterpillars.”

But apart from taking one for the team, the nasturtium is also a magnet for beneficial insects. “Their leaves,” says Jane, “provide insect-sized water sources.” And if the good bugs are happy, then chances are your vegetables will be happy, too.

Location: Full sun to semi-shade

Height: 30–60 cm

Good Companions: All-round good companion

Planting information: extracts from Jane's Delicious Garden by Jane Griffiths. Sunbird Publishers. For more information on companion planting, visit www.janesdeliciousgarden.comand www.aristonorganic.wordpress.com