4 Ways Marigolds Protect Your Vegetable Garden from Pests

Each garden center fills its shelves with endless flats of brilliant orange and yellow marigolds. Most people buy them simply because they're cheerful, easy to grow, and cheap. But smart vegetable growers know that marigolds are one of the most zealous security guards you can hire for your backyard garden.

If you want healthy tomatoes, crisp cabbage, and bug-free zucchini (green pumpkin) without having to sling scary chemical pesticides onto the food you eat, growing marigolds between your veggies is one of the laziest tricks in the organic gardener's book.

Here's how this humble flower protects your garden from hungry insects, both above and below ground.

The Pungent Scent Confuses Hungry Bugs

Have you ever been to sniff a marigold bush and noticed how strong, musky odor clings to your hands? Although we gardeners can't all agree on what that smell is, one thing's for sure--bad bugs hate it!

In the wild, bad bugs find your vegetables by smell. A whitefly or tomato hornworm moth doesn't read garden signs; it simply follows the trail of sweet-smelling tomato leaves, or the tender scent of cabbage to find its prey.

But if you plant marigolds right alongside your veggies, their intense, spicy aroma will mask the scent of your crops, like a smoky aroma wafting from a campfire.

Think of it as an aromatic smokescreen...

Scent Confusion: The bug is overwhelmed by the smell of marigold, thinks it has flown past a big patch of marigold, and goes bug-hunting on your neighbor's property instead.

Direct Repellent: Some pests like aphids, whiteflies, and Mexican bean beetles can't stand the natural oils of marigold leaves, and simply avoid areas where these plants grow.

Root Protection: Cleaning Dirty Soil

Some of the sneakiest critters who ruin gardens take up home in the dirt. Tiny, thread-like nematodes burrow into the roots of your favorite vegetables.

These little wormy pests infest the roots of tomatoes, peppers, potatoes, and carrots, creating ugly lumps that starve plants of nutrients. No matter how much you water or fertilize, plants with nematode-infested roots look sickly, yellow, and droopy.

Marigolds are known to solve this problem from the very soil up...

Natural Toxin: The roots of marigolds give off a natural chemical that is toxic to these pesky worms.

The Dead-End Trap: When a nematode tries to feast on a marigold root, the peculiar chemistry stops the worm from reproducing and causes it to starve.

If a garden bed produced wilted, undersized tomatoes last year, simply plant a thick bed of marigolds this season to naturally detoxify the soil for your next crop.

A Diner for the “Good Bugs”

Not every bug in your garden is your enemy. In fact, one of the easiest ways to get rid of pests is to let other insects eat them for you! Ladybugs, tiny wasps, hoverflies, and lacewings are the wolves of the garden world--they hunt and devour destructive pests like aphids, spider mites, and caterpillars.

But these “good guy” bugs need nectar and pollen to help them survive when their bug-snacking is slow. Marigolds are the all-you-can-eat buffet that keeps helpful insects housed and feeding in your garden all year long.

Ladybugs find shelter in thick marigold foliage, and scurry over to your vegetables to munch through hundreds of aphids each week.

Hoverflies look similar to tiny bees and are fond of marigold nectar! Their young are fierce little hunters who hunt and devour small garden pests.

Micro-wasps (which don't sting people) use marigold blossoms for fuel, while they hunt down big green tomato hornworms.

The “Sacrificial Lamb” Strategy

Sometimes marigolds protect your food by taking the hit themselves. We call this a trap crop. Pests like slugs, snails, and spider mites are far more interested in the tender young leaves of marigolds than in your prized vegetables. By creating a ring of marigolds around the edge of your bed:

Slugs that come out at night will first snack on the marigolds, leaving your delicate lettuce leaves alone.

Since these pests all congregate on your sacrificial lamb of marigolds, you can pick them off by hand in the morning, or simply spray down that ring of marigolds the next day.

Easy Guidelines for Planting Marigolds

Follow these three easy rules to get the most pest control power from your flowers.

Select French Marigolds (Tagetes patula): These are the short, stubby types with small blooms - red, orange mixtures to be found in most garden centers. They have the strongest root chemicals to fight off soil pests. Tall, broad “African” marigolds have huge golf-ball-sized blooms, are beautiful, but are weaker against underground insects.

Go for Simple Flowers: Avoid fluffy marigolds with a creamy yellow center. You want to find varieties where the yellow center of the bloom is easy to see. When the flower is puffed up with hundreds of ruffled petals (like the carnation), beneficial bugs can't get at the pollen inside.

Don't Put Them in a Distant Corner: Marigolds won't do much good if you have them tucked into a far corner as a decorative plant on your patio. Put them in the soil with your veggies, and space them every 2 or 3 tomato, pepper, or eggplant stalks.

By buying a six-pack of marigolds each Spring, you give your garden a natural, chemical-free security team that watches your food plants 24/7, while adding vibrancy to your dinner harvest.

Conclusion

You do not need to spend a fortune on expensive chemical sprays when the time comes to get rid of unwelcome pests on your beloved vegetables. Instead of buying artificial and toxic chemicals, plant some cheap marigold flowers among your vegetable beds. They will help you by masking the scent that may attract beetles, removing harmful worms from the soil, and calling ladybugs that will do the dirty work of killing the pests. This easy trick requires only a small amount of effort but can give you the reward of a plentiful harvest. Besides, it is an example of how sometimes the solution may be close to you.