18 of the Best Companion Plants for Basil (and Some to Avoid)

Basil is an absolute blessing to have in the garden, so it makes sense you would want to improve the chances of a big harvest. Companion planting basil with the right friends can increase your harvest and keep your plants healthier than ever.

Basil is fragrant and useful and it to me, is a signal of the warmth of spring and summer.

Let’s look at those companion plants you can utilize to increase your harvest of basil, and some to keep well away from your basil plants.

Perfect Conditions for Growing Basil

Six to eight hours of sunlight a day is a perfect position for basil. The soil pH should be between 6.0 to 7.5. Soil should also be nice and moist and free draining. Sandy, dry soil will cause the basil to become stressed.

The best-growing temperature is around 70ºF, and night temperatures shouldn’t drop below 50ºF.

Although it’s understandable to want to get basil in as soon as possible, don’t be hasty. Basil needs heat to thrive.

Keep the basil well watered.

Good Companion Plants to Grow With Basil

1. Tomatoes

Basil and tomatoes are probably the most perfect companion pairing. Wherever you place either plant, the other will work well and be happy.

I plant basil as a ground cover between my tomato plant rows. Basil produces an intense aroma that tomato hornworms hate and will avoid.

In return, tomato plants keep the soil healthy and in a condition that basil thrives in. Plant as much basil as will fit around your tomato plants.

2. Beets

Plant beets first, so that by the time you sow basil, the beets provide the young plants with shade.

Flea beetles love basil but are repelled by beets. Basil will repel pests from the beets, especially if you surround the beets with basil plants like a defensive ring.

3. Peppers

What do we mean by peppers? This could include:

• Bell Peppers
• Chilli Peppers
• Sweet Peppers

Even the hottest pepper cultivars attract pests that eat them, especially when the fruit is young. Planting with basil serves two purposes. Basil will act as a natural repellant to many of those pests, resulting in less need to spray, and basil enhances the flavor of peppers, especially sweet varieties.

4. Chives

The beauty of chives is they don’t take up much space and require very little maintenance. Chives give off an aroma that repels many pests including the ever-present aphid.

Planting chives with basil encourages the essential oil in the basil plant, giving more aroma and flavor.

The taller basil will provide chives with shade.

5. Rosemary

I like to plant new basil around my perennial rosemary herbs. Both plants give off aromas that repel many garden pests. Well-established rosemary has deep roots compared to the more shallow roots of basil so they don’t steal water or nutrients from each other.

When you remove the basil at the end of the season, you won’t disturb the hardy rosemary roots.

Allow some basil to go to seed and in the right environment. it will self-seed for the following season.

6. Garlic

Basil naturally repels many pests but can become overwhelmed at times. If it is heat-stressed, the soil has a lack of nutrients, or there are simply too many pests in one season, it may need a little help.

Try planting basil with garlic to prevent issues like this. Garlic repels many pests that are attracted to garlic like aphids and spider mites.

7. Lettuce

Whenever I think of a summer garden, I usually think of tomatoes, basil, and lettuce. If you are careful you can prevent the lettuce from bolting, and it makes a perfect companion to basil.

Basil enhances the flavor of lettuce and helps to prevent pests such as snails and slugs, which are attracted to the lettuce leaves.

8. Grapes

This may seem like an odd combination, and you may not want to plant grapes in your vegetable garden, but you can plant basil under your grape vines.

This works especially well if you have a food forest type of setup. The basil makes a great understory plant for the grapevine, and at the same time, the scent keeps many pests from finding the grapes.

The grapevine provides a little shade to the basil in the heat of the day.

Water well and the deep grapevine roots will get their share.

9. Potatoes

Plant basil within one to two rows of your potatoes. I try to have a row of basil one row from the potatoes on both sides. Basil helps to increase the flavor of potatoes and will repel serious potato pests.

Japanese beetles and Colorado potato beetles don’t like basil, and the scent of basil helps to keep them away, or at least keep numbers to a minimum.

10. Chamomile

Chamomile is good for the soil, and any plants it is near, due to the beneficial compounds the plant releases. This improves both the quality and flavor of basil.

Chamomile is loved by beneficial pollinators and insects that prey on basil pests like aphids.

11. Broccoli

Keep basil near broccoli, but not right next to it. Basil helps to protect broccoli from pests, but because broccoli can grow big leaves and cover the basil, give them some space.

One or two rows apart is sufficient.

12. Parsnips

Parsnips attract beneficial insects that feed on basil pests like aphids and spider mites. They also release a compound those pests would rather stay away from. Plant parsnip and basil rows next to each other, or within two rows.

13. Asparagus

If you’re lucky enough to have an asparagus patch, plant basil in and around it. Be careful not to disturb the asparagus roots, but the pairing is beneficial.

Asparagus attracts ladybugs which feed on aphids attacking basil. In return, basil repels the asparagus beetle.

14. Marjoram

Plant sweet or wild marjoram with basil because both benefit from the pairing. One of the best things about these two plants together is marjoram and basil have the same light, heat, soil, and water needs. Planting them close together works well.

Both plants attract beneficial insects and pollinators.

15. Anise

Also called aniseed, this flowering plant is a perfect companion to basil. It has antibacterial and antifungal properties which protect the basil from issues including rotting due to wet soil from heavy rain.

Due to the strong scents of basil and anise, pests are repelled effectively. Plant them together or within two rows of each other. The closer they are, the more anise will encourage oil in the basil leaves. This adds to the flavor of basil in your dishes and the scent in the garden.

16. Marigolds

Marigolds should be planted all around your gardens because they are so reliable at repelling pests. French marigold releases limonene from its roots into the soil.

This repels pests and assists neighboring plants even after the marigolds have died and been removed.

Plant marigolds in and around basil, and any other plants in the vegetable garden.

17. Nasturtiums

Some gardeners have a love-hate relationship with nasturtiums due to their ability to take over entire areas, and the amount of seed they drop to self-seed.

Plant the nasturtiums in containers near basil, or if you have a big patch of it, plant the basil nearby.

Nasturtiums should be used as a trap crop. You want it to attract pests away from the basil.

18. Petunias

Basil likes the presence of petunias (as do many other herbs) and thrives next to them. Petunias repel many pests including aphids, leafhoppers, and tomato worms.

Plants to Avoid Planting With Basil

As accepting of other plants as basil is, there are still some that won’t thrive next to it, or affect the basil causing a poor or bitter harvest.

1. Cucumber

Cucumbers tend to take over the garden they are planted in due to their vining nature. Basil doesn’t like this. Even if you trellis your cucumber, they will take too much water and the basil will suffer.

In the heat of summer, cucumbers often suffer from many diseases and these will be passed on to nearby basil.

2. Fennel

Fennel attracts pests that like basil so it’s not a good companion plant. It also stunts the growth of many plants it grows with.

Keep basil and fennel well away from each other.

3. Sage

The main reason sage and basil don’t get along is water. Basil prefers moist, well-draining soil. Sage prefers a more sandy, drier soil. One of the plants will suffer thanks to the preference of the other.

Keep basil and sage at least three rows apart.

4. Thyme

Similar to sage, thyme prefers a drier environment to basil. They don’t plant well together.

5. Common Rue

Sometimes known as herb-of-grace, common rue is one of the worst companion plants for basil. This is due to the fact it makes basil taste bitter.

Common rue not only attracts basil pests, but it also makes basil more susceptible to those pests. Any basil plants next to common rue will struggle.