Tomatoes may be the star of your garden, but they don’t have to grow alone.
With smart underplanting, you can use the space beneath your tomato vines to suppress weeds, attract beneficial insects, improve soil, and even enhance flavor.
The key is choosing plants that stay low, don’t compete for resources, and thrive in similar conditions. Here are ten plants that grow beautifully under tomatoes and actually help them along the way.
1. Basil
Basil and tomatoes are more than just culinary companions, they’re gardening soulmates. Basil grows well in the warm, sunny conditions tomatoes love, and it doesn’t take up much space.
Its strong aroma is believed to repel pests like aphids, whiteflies, and hornworms. Some gardeners even swear that tomatoes grown next to basil taste better.
You can plant basil in clumps around the base of each tomato plant, giving them just enough room to breathe.
Harvesting basil regularly encourages bushier growth and helps shade the soil below, reducing moisture loss and weed competition.
2. Marigolds
Short marigold varieties (like French marigolds) can be tucked under tomato plants for a powerful one-two punch.
Not only do they deter nematodes and beetles in the soil, but their bright flowers also attract pollinators and beneficial predators like hoverflies and lacewings.
Their shallow roots and compact growth habit make them ideal underplanting partners.
Plus, they bring a cheerful pop of color to your veggie beds and don’t compete with your tomatoes for nutrients or sunlight.
3. Nasturtiums
Nasturtiums are a gardener’s secret weapon. They sprawl as a living mulch beneath tomatoes, helping to suppress weeds, retain moisture, and cool the soil.
But they’re also excellent trap crops, drawing aphids and whiteflies away from your tomato plants.
Let nasturtiums trail around the base of your tomatoes or cascade over the edge of raised beds. Their edible, peppery flowers and leaves add beauty and flavor to salads.
4. Garlic
Garlic doesn’t just flavor your kitchen, it protects your garden. Its strong sulfur-rich scent repels spider mites, aphids, and even rabbits.
Garlic is shallow-rooted and slim, meaning it won’t crowd your tomato roots or block airflow.
You should plant garlic cloves around the perimeter of each tomato bed in early spring or fall. It grows slowly but steadily under taller crops.
As a bonus, you can harvest garlic scapes early in the season while the bulbs continue developing below.
5. Lettuce
Lettuce grows low and wide, making it the perfect underplanting crop, especially in spring and early summer before the tomato canopy fills in.
It matures quickly and doesn’t compete heavily for nutrients, offering a low-maintenance harvest beneath your taller tomatoes.
Once tomato vines start casting shade, lettuce can keep growing without bolting too quickly.
You can interplant butterhead, romaine, or looseleaf types between tomato rows, harvesting them gradually before they crowd the space.
6. Chives
Chives are another aromatic herb that pulls double duty. Their scent repels aphids and thrips, and their pretty purple blossoms attract bees and parasitic wasps.
Chives stay small and clump neatly, so they won’t interfere with tomato roots or airflow.
You plant chives around the base of your tomatoes or at the corners of your raised beds. They’re perennial in many climates, meaning you can divide and replant them yearly for consistent benefits.
7. Spinach
Spinach is a cool-season leafy green that fits naturally under tomato vines early in the growing season.
You can plant it as a groundcover between tomato seedlings. As tomatoes get taller, their spreading leaves help shade the spinach, keeping it cool and delaying bolting.
Spinach roots are shallow and won’t compete with tomatoes for deeper nutrients. By the time the tomatoes need more space, your spinach will be ready to harvest, leaving room for airflow and mulch.
8. Calendula
Calendula, also known as pot marigold, is a friendly flower that benefits tomatoes in several ways.
It attracts pollinators, improves biodiversity, and draws in beneficial insects that feed on common tomato pests like aphids and whiteflies.
Unlike tall perennials, calendula grows in a tidy mound with gentle blooms in orange, yellow, or cream. You can plant them at the edges or underneath open tomato cages without creating congestion.
9. Carrots
Believe it or not, carrots can grow beneath tomatoes if spaced thoughtfully. Their long taproots dig deep while tomato roots stay mostly in the topsoil.
As long as you avoid compacting the space and thin the carrot seedlings properly, you’ll have a hidden harvest developing beneath your tomatoes.
Tomato foliage provides just enough shade to help carrots stay cool, which improves both their texture and flavor. Just be careful when watering as both crops prefer consistent moisture.
10. Parsley
Parsley is an underrated tomato companion. It acts as a light groundcover, attracts hoverflies and beneficial wasps, and doesn’t hog space.
Since it’s a biennial herb, it will grow quietly under your tomatoes the first year and flower the second, providing even more insect-friendly benefits.
You plant parsley seedlings in spring, and harvest as needed. It handles a bit of shade and prefers the same moderate moisture levels tomatoes love.
Bonus Tips for Underplanting Tomatoes
When growing plants under tomatoes, it’s important to maintain balance and airflow. Avoid overcrowding, especially under dense foliage. Tomatoes need good ventilation to prevent fungal issues like blight.
Stay away from aggressive spreaders or nutrient hogs like mint, broccoli, and members of the cabbage family tend to compete too much and don’t make good companions here.
Instead, you should choose plants that fill in gaps gently and contribute to the health of the garden.
Also, low-growing plants help cool the soil, retain moisture, and prevent weeds, all while supporting the ecosystem beneath your tomatoes.
Read more: How to Prune Tomato Plants Like a Pro for Bigger, Juicier Harvests
Final Thoughts
Tomatoes are heavy feeders, but that doesn’t mean they need to grow in isolation.
With the right plant partners underneath them, you can improve your garden’s health, attract helpful insects, conserve water, and even increase your harvest, all without overcrowding your tomatoes.
