Tomatoes are the star of most home gardens, and they’re also a favorite of hornworms, aphids, whiteflies and plenty of diseases. Choosing the right neighbors can make your tomato bed healthier, more productive and easier to manage.
Here are the best companion plants for tomatoes, what each one actually does, and the plants you should keep at a distance.
The Best Companion Plants for Tomatoes
1. Basil
The classic pairing. Basil grows well in the light shade under tomato plants, and its flowers feed pollinators and beneficial insects. A few studies have found fewer thrips on tomatoes grown with basil and marigolds. And of course, the two go perfectly together in the kitchen.
2. Marigolds
French marigolds attract hoverflies and other beneficial insects and add color to the bed. Some varieties can help reduce root-knot nematodes, but research shows this works mainly when marigolds are grown densely and then turned into the soil, not from a few plants scattered around.
3. Carrots
Carrots grow below ground and take up little space above it, so they fit neatly between tomato plants. Let a few carrots flower, too: their blooms attract tiny beneficial wasps.
4. Lettuce and spinach
Sow leafy greens around young tomato plants in spring. They’ll be harvested before the tomatoes grow big, and later the tomato foliage gives them welcome shade as the weather warms.
5. Onions, garlic and chives
Alliums take up little room and fit around the edges of a tomato bed. Their strong scent may help mask tomatoes from some pests, and chive flowers attract pollinators.
6. Parsley
When parsley flowers in its second year, it feeds hoverflies and parasitic wasps that help keep aphids and caterpillars in check.
7. Nasturtiums
Plant nasturtiums a short distance from your tomatoes as a trap crop. Aphids often go to them first, so you can spot and remove the pests before they reach your tomatoes.
8. Borage
Borage’s blue flowers are a magnet for bees, which can improve pollination across the whole bed. It grows large and self-seeds freely, so give it room and pull extra seedlings.
Plants to Keep Away From Tomatoes
- Potatoes: same plant family as tomatoes. They share early and late blight, so growing them together makes diseases spread more easily.
- Corn: the corn earworm and the tomato fruitworm are the same insect. Growing them side by side gives it two favorite foods in one place.
- Cabbage, broccoli and kale: heavy feeders that compete with tomatoes for nutrients and water.
- Fennel: slows the growth of many vegetables nearby. Grow it in its own pot or corner.
- Eggplant and peppers in the same spot every year: they’re fine neighbors, but they share diseases with tomatoes, so rotate the whole family to a new bed each year.
A Simple Tomato Bed Layout
For a 4 x 8 foot raised bed, try this easy plan:
- Plant 3 tomatoes down the center, about 2 to 3 feet apart, with sturdy cages or stakes.
- Tuck a basil plant at the base of each tomato.
- Sow a row of carrots along one long side, and lettuce or spinach along the other.
- Put a marigold in each corner and a few chives along the ends.
- Plant nasturtiums in a pot or patch a few feet away as a trap crop.
Tips for Healthy Tomatoes
- Give them space and airflow. Crowded tomatoes stay damp and get more leaf diseases.
- Water at the base. Wet leaves spread disease; use a soaker hose or water the soil directly.
- Mulch. A layer of straw or shredded leaves keeps soil from splashing onto the lower leaves.
- Rotate. Avoid planting tomatoes, peppers, eggplant or potatoes in the same spot more than once every 3 years.
- Check for hornworms. Look under leaves for large green caterpillars and pick them off by hand.
Want the full picture? See our companion planting chart for vegetables, and check which plants shouldn’t be grown together.
Frequently Asked Questions
Does basil really make tomatoes taste better?
There’s no solid evidence that basil changes the flavor of tomatoes. But it grows well alongside them, and they taste fantastic together on the plate.
Can I plant tomatoes and peppers together?
Yes. They like the same sun, soil and water. Just remember they belong to the same family, so rotate them together to a new bed each year.
How far should companion plants be from tomatoes?
Low herbs like basil and parsley can go 10 to 12 inches from the stem. Keep larger plants like borage 2 feet or more away so they don’t compete for light and water.
