Landscape Logic column: Create companionship in your garden |

Landscape Logic column: Create companionship in your garden

Becky Garber
Landscape Logic
Greenhouse tomato cultivation
Getty Images/iStockphoto | iStockphoto

Many plants thrive on being placed close to one another. Take tomatoes and basil, for example. They’re a marriage made in heaven even before they get to the kitchen.

What experienced gardeners call “companion plants” will bring in good insects for the benefit of the whole garden. Others will drive bad bugs away. And some, like tomatoes and basil, thrive best together than when planted apart. All you need to know is who loves who in the plant world.

Basil improves the growth and flavor of tomatoes and will also repel thrips — a common Colorado garden pest. If you add the typical Italian herbs to the mix by planting parsley, oregano and thyme, you will enhance the winning garden combo. Oregano is a flavorful herb that provides overall pest protection throughout the garden.

Add flowering plants that do more than look pretty

Alyssum – Plant it alongside potatoes and broccoli. It attracts delicate beneficial insects, such as predatory wasps and attracts hoverflies whose larvae devour aphids.

Chrysanthemum – It has been used as botanical pesticides for centuries. White flowering chrysanthemums repel Japanese beetles.

Lavender — Attracts butterflies and bees and repels fleas, whitefly and moths.

Marigolds – Well known as a pest deterrent. They keep soil free of bad nematodes, beetles and whiteflies and discourage many other insects. Plant freely throughout the garden but avoid bean and cabbage plants. Marigolds must be a scented variety for them to work. Downside: they can attract spider mites and slugs.

Nasturtium — Great companion to radishes, cucumber, cabbage, cauliflower, broccoli and mustards. It deters aphids, squash bugs and striped pumpkin beetles and improves both growth and flavor. Since it likes poor soil with low moisture and no fertilizer, set potted nasturtiums among garden beds. The leaves, flowers and seeds of nasturtiums are all edible and great in salads.

Zinnias — Attract hummingbirds which eat whiteflies. Pastel varieties can be used as a trap crop for Japanese beetles. All zinnias attract bees and other insect pollinators.

Herbs and other flavorful plants are also good companions

Catnip — Deters flea beetles, aphids, Japanese beetles, squash bugs, ants and weevils. It also helps to repel mice.

Chamomile, peppermint, dill, sage and rosemary — Plant these with broccoli, cauliflower and cabbage. Chamomile is also a host to hoverflies and wasps.

Chives — Improves growth and flavor of carrots and tomatoes and also work well with broccoli, cabbage and mustard. Chives repel aphids from tomatoes and grapes. Avoid planting them near beans and peas.

Cilantro (coriander) — Repels aphids, spider mites and potato beetle.

Dill – Plant with cucumbers to attract beneficial predators. Also repels aphids, spider mites and squash bug. Dill improves growth of cabbage and lettuce. Do not plant near carrots, caraway, cauliflower, corn, potatoes or tomatoes.

Garlic – Plant with beets for flavor and pest control. Plant near roses to repel aphids. It also benefits cukes, peas, lettuce and celery. Garlic accumulates sulfur, a naturally occurring fungicide which will help prevent disease.

Onions (Alliums) – Plant with carrot, chamomile, beets, strawberries, broccoli, dill, lettuce, summer savory and tomatoes. Onions planted with strawberries help the berries fight disease. Keep onions away from peas and asparagus.

Sage – Plant with broccoli, cauliflower, rosemary, cabbage, and carrots. It deters cabbage moths, beetles, black flea beetles and carrot flies. Do not plant near cucumbers or onions. Allow sage to flower so it will attract many beneficial insects.

Tarragon – Plant throughout the garden as few pests like it. It also enhances growth and flavor of vegetables.

Becky Garber is a member of the Associated Landscape Contractors of Colorado of which Neils Lunceford, a landscaping company, is a member. You can contact them at 970-468-0340.

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