Companion Planting with Herbs

Boost your garden this season with the right pairings of plants.

Companion planting is a fantastic addition to any garden. By specific plants next to certain fruits, flowers, and vegetables, you can boost their health and increase their production. Of course, knowing what pairings work best is key, especially when it comes to herbs.

How It Works

Companion planting improves growth in a number of ways. To start, some plants serve to repel unwanted pests while providing shelter and safety for beneficial insects. Others encourage pollination, which is especially needed for those fruits and vegetables that don’t have noticeable flowers. Species with bright shades of blue, white, or yellow and/or with high concentrations of nectar can attract bees to these lesser-flowered plants. Larkspur, sunflowers, sweet peas, cosmos, zinnias, and mints all do well in vegetable gardens {though the mint does spread quickly}. Companion planting is a wonderful tool for organic gardeners, too, since it reduces the need for synthetic fertilizers and chemical herbicides and pesticides.

Herbs, in general, make excellent companion plants. They’re often responsible for increasing vegetable bounty by attracting bees and beneficial insects with their blossoms and fragrance. They grow easily between rows of vegetables without causing harm to the vegetable plant, and as light feeders, they don’t rob important nutrients from the soil that vegetables need.

Before you grow anything, make sure to research your plant’s moisture, nutrient, and shade/sunlight needs. Obviously, growing conditions must be met for both plants in order for them to succeed and help each other out.

Longtime Companions

Companion planting is not a new concept by any means. More than 300 years ago, the Iroquois introduced early American colonists to the “Three Sisters” technique of planting corn, beans, and squash together. Tall corn provides trellis support to beans, which in turn take important nitrogen from the cells of bacteria in the soil. This helps feed the squash or pumpkins which are considered heavy feeders. The squash and pumpkin plants keep the weeds at bay by shading the growing area, and they leave important nutrition for the sister plants. Some experts believe this type of planting has been around for 6,000 years, and this method is still practiced successfully today, with sunflower often taking the place of corn.

Today we may be more familiar with the tomato-basil companion pairing. When basil leaves are rubbed or disturbed, they release the chemical compounds nerolidol, citronellal, limonene, and estragole, which repel mosquitoes and flies and also act as fungicides. Some argue that leaving basil on windowsills and terraces can keep the pests away. Of course, the bonus of this pairing is creating a wealth of delicious tomato-basil dishes, including Caprese salad.


Perfect Pairings

So, how do you apply companion planting to your garden plot? Here are some favored herbs that help boost your overall growth.

Anise {Pimpinella anisum}: Planting this fragrant herb in the middle of your flower beds attracts predatory wasps. Its strong scent also repels aphids, making it a great companion next to beans, which aphids love to snack on and devour. Anise produces white, lacy flowers on 18- to 36-inch stems which can provide shade for lower-growing plants. It’s also a companion to cilantro, and both plants create nice height for the back of the garden.

Anise Hyssop {Agastache foeniculum}: This tall, purple plant is a favorite of honey bees – perfect for pollinating. Hyssop promotes the growth of grapes, as well as cauliflower and cabbages. Planting Brussels sprouts near hyssop is actually beneficial to the hyssop plants. The hyssop keeps the cabbage moth away from the sprouts and some gardeners attest that hyssop growth is encouraged by its proximity to this vegetable.

Basil {Ocimum basilicum}: This summertime herb doesn’t just help tomatoes. Its chemical compounds also deter asparagus beetles, as well as aphids, milkweed insects, and flies. {Just don’t plant it by rosemary or sage; these herbs make poor companions.}

Borage {Borago officinalis}: We may know it best for its medicinal benefits, but borage also pairs well with tomatoes by repelling those hideously huge tomato worms! According to the site, “The most beneficial plant to plant in close proximity to strawberry plants is likely the culinary herb borage,” because of its ability to attract beneficial predatory insects like praying mantis and predatory wasps.

Caraway {Carum carvi}: Plant this herb anywhere in the garden. It loosens the soil with its long, eight- to -nine-inch roots to help other plants set root. {Don’t plant it near fennel, however; the two herbs hinder each other’s growth.}

Chervil {Anthriscus cerefolium}: If your planting radishes, don’t forget the chervil! This herb naturally enhances the growth and taste of those crunchy veggies.

Chives {Allium schoenoprasum}: Plant chives near carrots in the garden and they will deter the carrot rust fly, thanks to their sulfuric odor, which repels these damaging bugs. Additionally, their large, purple flower heads attract good insects such as butterflies and bees, which help pollinate nearby companions.

Chives do well with strawberries. Their odor masks the sweet scent of the berries, deterring would be insect pests. Chives also provide calcium and potassium, which strawberries need for growth. {Chives are not helpful to beans or peas.}

For a homemade, all-natural pesticide, put chives, water, and a small amount of dish soap in a blender and mix. Spray on plants to repel pests and to keep powdery mildew in check.

Dill {Anethum graveolens}: Dill is recommended as a wonderful companion plant for a wide range of garden vegetables. It benefits corn, onions, cucumbers, asparagus, lettuce, and all vegetables in the cabbage family, such as Brussels sprouts and broccoli. Planted by tomatoes, dill will keep horned worms away while at the same time encouraging beneficial insects, including praying mantis and ladybugs. Young dill plants improve the flavor and enhance the growth of tomato plants. However, as dill ages it can stunt the growth of these vegetables, so monitor your tomato plants carefully. {Please be cautious about planting dill anywhere near fennel or cilantro. The herbs will cross-pollinate, which can diminish flavor. Dill also inhibits carrot growth when planted nearby.}

Garlic {Allium sativum}: This pungent herb is most helpful when planted by raspberries and roses. Its strong aroma and taste also repel pests from beets, sweet peppers, parsnips, spinach, and lettuce. It also feeds beneficial soil microbes with substances exuded by its roots, and it produces a natural, non-selective fungicide that repels pests. {Planting it near potatoes has been known to stunt their growth and should be avoided.}

Geraniums {Pelorgonium spp.}: Corn, roses, cabbages, and grapes all thrive when planted near geraniums. Cabbage worms, Japanese beetles, and earworms pose a threat to these plants, but scented geraniums keep them away. They also repel spider mites, which can devastate a vegetable garden in the heat of summer. For best results, intersperse geraniums among your plants or create a border around the perimeter of the garden.

Lavender {Lavandula spp.}: This herb’s lovely floral scent attracts gardeners and many pollinating insects. But it also repels several types of beetles and flies, as well as mice and rabbits. The UK’s Jersey Lavender Farm notes that some evidence indicates that lavender planted under apple trees keeps codling moths away.

Lavender is a hardy perennial. When planted in the center of a garden it will thrive and benefit its neighboring plants. It makes an excellent companion to broccoli, cabbage, kale, and cauliflower because it doesn’t compete with them for nutrients.

Lovage {Levisticum officinale}: This is an all-purpose companion plant. Grow lovage in several areas of your garden, and it will improve the flavor and health of most surrounding species.

Marigolds {Tagetes spp.}: If your growing basil, tomatoes, cucumbers, potatoes, squash, eggplant, kale, gourds, carrots, or beets, don’t forget the marigolds – this herb invites pollinators to the garden. Certain species of marigolds also release compounds from their roots that are toxic to root nematodes, which ruin plants by feeding on this part of the plant. {Some argue that marigolds combat nematodes by acting as a trap crop rather than actually eradicating the insects.}

The Trap Crop Garden

This twist on companion planting uses the companion plant as a “sacrificial” species. It’s a method of planting one species in order to save another. When you can’t seem to repel pests, plant a sacrificial crop around the fruit or vegetable you’re trying to save. For instance, you might plant collard greens around a cabbage crop that’s being invaded by pests. When the diamondback moths come to attack your cabbage crop, the more appealing collards entice them away. Eventually, you’ll have to pull up and dispose of the munched-on collards, but your cabbage should remain intact. Nasturiums, which attract aphids, are often sacrificed in favor of certain crops, such as tomatoes.

Marjoram {Origanum majorana}: This culinary herb is believed to stimulate growth in all surrounding plants. It may be planted safely in any area of your garden, and the flowers of this herb attract bees and other pollinators. Some of the best companion plants for marjoram include celery, eggplant, potatoes, radishes, corn, onions, and peas.

Flavoring some of these vegetables with marjoram is quite delicious. {Use the herb raw for best flavors.}

Marjoram grows exceptionally well itself when planted next to stinging nettle. Growing near nettles strengthens the essential oil found in marjoram and creates a more distinct flavor and scent for the herb.

Mint {Mentha spp.}: Mint is a very helpful herb. It offers growth assistance to several vegetables, including broccoli, Brussels sprouts, bell peppers, chili peppers, eggplant, kale, kohlrabi, squashes, and lettuce. Thanks to its minty-fresh scent, the herb discourages carrot and onion flies and deters aphids away from tomatoes and roses.

Catmint or catnip is especially useful in ridding your garden of insects and aphids. As with all mints, catnip is very invasive, so be sure to plant this herb in pots, and then bury the pots in the garden.

Fennel: Friend or Foe?

Fennel {Foeniculum vulgare} is not a good companion plant for any garden. The only herb safe to plant near fennel, according to some gardeners, is dill. However, in most cases, this is not a good option either as the two herbs usually cross-pollinate. This herb is allelopathic to most plants. Fennel puts out a chemical through its roots which diminishes the growth of some plants, causes others to bolt, and actually kills some. This seemingly toxic, although delicious plant is best planted away from all other vegetables and herbs.

Oregano {Origanum vulgare}: Although oregano has no particular companion, it serves well anywhere in the garden. The oregano flower attracts butterflies to the yard, as well as mud dauber wasps, which feed on several different kinds of chomping caterpillars.

Parsley {Petroselinum crispum}: This herb is a companion to many of the vegetables it pairs within the kitchen, including corn, asparagus, tomatoes, carrots, peppers, onions, peas, and chives. It also enhances the flavor of potatoes. Parsley encourages the growth of these vegetable plants and actually does its best work next to asparagus because it helps repel asparagus beetles.

The herb also attracts adult swallowtail butterflies, which lay their eggs on the leaves, thereby encouraging pollination despite not having its own flowers.

When allowed to go to seed, parsley will attract hoverflies to your garden. With some species of hoverflies, the larvae are known to eat aphids, thrips, and other destructive insects.

Rosemary {Rosmarinus officinalis}: Cabbage, cauliflower, and broccoli all get a boost by their proximity to rosemary plants. The aroma of the herb confuses the cabbage butterfly {also called cabbage white} and repels several types of flies and beetles. Don’t plant rosemary near squash, pumpkins, potatoes, or carrots. It will inhibit their growth.

Sage {Salvia officinalis}: rosemary and sage are wonderful companions, and some believe that they enhance each other’s flavors. Sage also supports cabbage and carrots by keeping cabbage moths and carrot rust flies at bay. Keep this herb away from cucumbers. The aroma of sage has a negative impact on the growth of this vegetable and damages its flavor.

A wonderful culinary herb, sage pairs well with soups, salads, beans, and peas, and also tastes great in cheese dishes. It’s a great substitute for flavor in salt-free cooking.

Summer Savory {Satureja hortensis}: This herb repels black fly from broad beans, and some gardeners swear by it as an herb that promotes the growth and flavor of onions. For a delicious bean side dish, prepare runner beans or broad beans with a clove of garlic, a dash of cream, and a generous amount of summer savory.

Tarragon {Artemisia dracunculus}: Tarragon pairs well with most plants in the garden – it doesn’t negatively impact any other species and it works as a general deterrent to harmful pests. Planted nearby, tarragon purportedly enhances the flavor of eggplant.

This herb not only works well with poultry, eggs, and meat but also seafood. Use it in marinades and salad dressings to add a little kick to your garden bounty.

Thyme {Thymus vulgaris}: Plant this earthy herb near the cabbage plants in your garden, and you’ll help to repel cabbage worms away from your crop. It seems the aroma of thyme deters these pests. Thyme also greatly enhances the flavor of potatoes, both in and out of the garden.

Hopefully, you will find success with some of these herb-crop pairings this season. Take a walk around the garden and jot down some notes to make a record of which companions seem to work best. Over time, you will have a better understanding of these beneficial relationships – and which ones work best for your garden plot.