Plant basil and tomatoes together in the same bed or container
Basil and tomatoes grow well side by side because they have similar water and sunlight needs, and basil's strong smell may help mask tomato plants from some pests. You can plant them in the same garden bed, in adjacent rows, or even in the same large container. The key is giving each plant enough space to develop roots and leaves without crowding.
Basil is a warm-season herb that thrives in the same conditions as tomatoes—full sun, consistent moisture, and soil that drains well. Unlike tomatoes, basil is an annual in most climates, meaning it lives only one growing season. This makes it straightforward to plant after your tomatoes are already in the ground, or to start both at the same time if you're beginning from seed.
Key Takeaways
- Plant basil at least 6 to 12 inches away from tomato plants so both have room to spread their roots and leaves without competing.
- Wait to plant basil until soil temperature reaches 60°F or higher, or start seeds indoors 6 weeks before your last frost date and transplant seedlings after frost danger passes.
- Water basil and tomatoes at the soil level early in the morning, keeping soil consistently moist but not waterlogged, to prevent disease and root rot.
- Pinch off basil flower buds as they form to encourage bushier leaf growth and extend the harvest through the growing season.
- Harvest basil leaves regularly by pinching or cutting from the top of the plant, which keeps it productive and prevents it from flowering too early.
Space basil 6 to 12 inches from tomato plants
The distance between basil and tomatoes matters because both plants need room for their root systems to spread and their leaves to receive sunlight. Plant basil at least 6 inches away from a tomato plant's main stem if you're placing it in the same bed. If you have space, 12 inches is even better and gives you room to move between plants without brushing foliage.
In a container, use a pot that is at least 18 to 24 inches wide and 12 inches deep for one tomato plant and two or three basil plants. Arrange the basil around the edge of the pot, leaving the center for the tomato. This setup works best with determinate tomato varieties (bush types that stay compact) rather than indeterminate varieties (vining types that grow tall and sprawl).
If you're planting in rows, space tomato plants 24 to 36 inches apart and tuck basil plants into the gaps between them. Basil stays much smaller than tomatoes and won't shade them out as long as you keep it trimmed back.
Start basil seeds or transplants at the right time
Basil is sensitive to cold and will not germinate or grow if soil temperature is below 60°F. If your tomatoes are already in the ground and soil has warmed, you can direct-seed basil right into the garden bed. Sprinkle seeds where you want them, press them lightly into the soil, and keep the area moist until seedlings emerge in 5 to 10 days.
If you want basil to be ready when you plant tomatoes, start seeds indoors about 6 weeks before your last spring frost date. Plant seeds in seed-starting mix in small pots or trays, keep them warm (70°F to 75°F), and provide bright light once they sprout. Transplant seedlings outdoors after your last frost date has passed and soil has warmed.
Buying basil transplants from a nursery is the fastest route if you don't want to start from seed. Look for stocky, green plants with no flowers. Harden them off by setting them outside in a sheltered spot for a few hours each day for 3 to 5 days before planting them in the garden, so they adjust to outdoor conditions without wilting.
Water basil and tomatoes at soil level in the morning
Both basil and tomatoes need consistent moisture—soil should feel damp a few inches down, but never soggy or waterlogged. Water early in the morning so foliage dries quickly, which reduces the risk of fungal disease. Aim to water at the base of the plants, keeping water off the leaves.
In hot weather, you may need to water every day or every other day, depending on how fast soil dries. Stick your finger into the soil near the plants; if it feels dry at the first knuckle, it's time to water. Container plants dry out faster than garden beds, so check them daily during summer.
Mulch around the base of both plants with 1 to 2 inches of straw or shredded leaves. Mulch keeps soil cooler and moister, reduces weeds, and prevents soil from splashing onto leaves during watering—another way to prevent disease.
Pinch off basil flowers to extend the harvest
Basil flowers are edible and attractive, but once the plant starts flowering, it stops producing new leaves and begins to decline. To keep basil leafy and productive through the season, pinch off flower buds as soon as you see them forming at the top of the stems. This redirects the plant's energy into making more leaves instead of seeds.
Pinching also makes basil bushier. When you remove the top of a stem, two new stems grow from the leaf nodes below, creating a fuller plant with more leaves to harvest. Do this regularly from the time the plant is 6 inches tall until late summer, when you can let it flower if you want seeds for next year.
Harvest basil leaves regularly throughout the season
Start harvesting basil leaves once the plant has at least 6 to 8 leaves and is 6 inches tall. Pinch or cut leaves from the top of the plant, removing no more than one-third of the foliage at a time. Regular harvesting keeps the plant productive and encourages branching.
Pick leaves in the morning after dew dries but before the day gets hot. Basil leaves are most flavorful at this time. You can harvest individual leaves or pinch off entire stem tips with 2 to 3 leaf pairs attached. Use fresh basil right away, or store it in a glass of water on the counter like a bouquet, or wrap it loosely in a damp paper towel and refrigerate for up to a week.
In late summer, as temperatures cool, basil will slow down and eventually stop growing. At that point, you can let it flower, harvest the flowers for tea or garnish, and collect seeds if you want to grow basil again next year. Or straightforward pull out the plant and compost it.
Watch for common pests and diseases
Basil and tomatoes can attract some of the same pests—aphids, spider mites, and whiteflies—but basil's aromatic oils may actually deter some insects from tomatoes. Check the undersides of basil leaves weekly for tiny insects or sticky residue. If you spot pests, spray the affected area with a strong stream of water from the hose, or use insecticidal soap if the problem persists.
Fungal diseases like powdery mildew and leaf spot can affect both plants, especially in humid conditions or when foliage stays wet. Water at soil level, space plants for good air circulation, and remove any yellowing or spotted leaves promptly. If disease spreads, remove the affected plant to prevent it from spreading to nearby tomatoes.
Frequently Asked Questions
Can I plant basil in the same pot as a tomato plant?
Yes, if the pot is large enough—at least 18 to 24 inches wide and 12 inches deep. Plant the tomato in the center and basil seedlings around the edges. This works best with compact, determinate tomato varieties rather than tall, sprawling types that will shade out the basil.
What if basil flowers before I want it to?
Pinch off the flower buds as soon as they appear at the top of the stems. This redirects the plant's energy into leaf production and keeps it bushy and productive. If you miss some flowers, straightforward remove them and continue harvesting leaves as normal.
How often should I water basil and tomatoes together?
Water when the top inch of soil feels dry, which is usually every day or every other day in hot weather. Water at the base of the plants in the morning so foliage dries quickly. Soil should be consistently moist but never waterlogged, or roots will rot.
Can I harvest basil while tomatoes are still growing?
Yes, harvest basil regularly throughout the season. Start once the plant is 6 inches tall and has at least 6 leaves. Regular harvesting keeps basil productive and bushy and won't harm your tomato plants, since they're growing independently.
What should I do with basil at the end of the season?
As temperatures cool in fall, basil will slow down and stop growing. You can harvest the last leaves, let it flower and collect seeds for next year, or pull out the plant and compost it. Basil is an annual and will not survive a hard frost.