Tarragon repay a little planning around what grows beside them. Tarragon are a slender perennial herb with an anise flavour, prized in French cooking, grown for cooking, and a tidy upright plant for the herb bed. They need full sun, soil with a pH of 6.0–7.5, 18–24 inches of space and 60–90 days to reach maturity, so their neighbours need to suit the same bed and the same season. This guide lists the companions for tarragon from our crop data, how each one is thought to help, and which close relatives to keep apart.
There are 4 companions listed for tarragon here: Tomatoes, Peppers, Marigolds and Cabbage. Companion planting is traditional garden practice rather than proven science, so benefits below are described in those terms — what gardeners have long said and done. Tarragon are in the Asteraceae family, need low water, and are started indoors or sown direct; they are hardy and tolerate cold, so they can go out early in the season. Check any pairing first with the companion-planting finder.
Best companion plants for tarragon
| Companion | Why it is grown with tarragon |
|---|---|
| Tomatoes | A tall, sun-loving neighbour for the same warm bed; plant the herb at the sunny edge so it is not shaded out, and keep spacing generous for airflow. |
| Peppers | Another heat-lover for the same sunny bed; its upright habit leaves room at its feet for low herbs. |
| Marigolds | Grown as a border or dotted through the bed; its roots are traditionally said to discourage some soil pests, and its flowers attract beneficial insects. |
| Cabbage | Tarragon's scent is traditionally said to help mask cabbage, and it likes the same sunny, well-drained spot. |
Tomatoes are the first companion to reach for with tarragon, and it is a quiet, upright neighbour that asks for little — sun, drainage and room to reach its full height. It is the tall neighbour that sets the shape of the bed: stake it well, keep the lower leaves clear, and plant the herb at its sunny base where it gets light without being shaded out.
How companion planting works
Companion planting works through four overlapping mechanisms.
Pest confusion. Many pests find their host plant by scent. Strong-smelling companions such as aromatic herbs are traditionally said to mask that scent, so the pest passes by. It is a delaying effect, not a barrier.
Pollinator and beneficial-insect attraction. Several companions here flower — Marigolds — drawing pollinators and beneficial insects in. Let a few flower.
Nitrogen fixing. Nitrogen fixing does not apply here — none of the listed companions is a legume.
Ground cover and root layers. No companion here is a ground-cover plant, so mulch does that job instead. Deep roots beside shallow ones also compete less for water and nutrients.
None of this replaces the basics. Spacing, watering, rotation and weekly inspection matter more than any pairing.
Plants to avoid near tarragon
The plants to keep away from tarragon are its own relatives. Tarragon belong to the Asteraceae family, and plants in the same family share the same pests and diseases — here, aphids, slugs, thrips — so problems pass easily between them and build up in the soil.
| Plant to avoid | Why |
|---|---|
| Lettuce | Same Asteraceae family; shares pests such as aphids, slugs, thrips. |
| Artichokes | Same Asteraceae family; shares pests such as aphids, slugs, thrips. |
| Romaine Lettuce | Same Asteraceae family; shares pests such as aphids, slugs, thrips. |
| Iceberg Lettuce | Same Asteraceae family; shares pests such as aphids, slugs, thrips. |
| Chamomile | Same Asteraceae family; shares pests such as aphids, slugs, thrips. |
Keep these relatives in a different bed and rotate the Asteraceae family to fresh ground each year. Others in the same family in our crop data include Stevia, Sunflowers, Zinnias, Dahlias, Cosmos, Calendula, Asters, Chrysanthemums.
One overlap to note: Marigolds also belongs to the Asteraceae family, so it shares some pests with tarragon. It stays on the companion list above because our crop data lists it as a companion of tarragon — gardeners still grow it together — but give it its own space, keep the bed aired, and watch it for aphids, slugs, thrips.
Planting layout and spacing
Space plants 18–24 inches apart in well-drained soil and avoid overwatering; tarragon roots rot in soil that stays wet.
Give tarragon their full spacing of 18–24 inches between plants. Crowded tarragon mean poor airflow, more disease and smaller harvests, and no companion plant compensates for it. Work out how many plants fit your bed with the plant-spacing calculator or the square-foot garden planner.
Plant companions in the spaces the spacing leaves, not instead of it. Low companions go in the gaps and along the bed edges; taller ones go at the north side so they do not shade the tarragon; scented herbs go closest to the crop, dotted through the row.
Tarragon are started indoors or sown direct: sow under cover where needed, expect germination in 10–14 days, and set plants out once the weather is right. Work backwards from your last frost date with the seed-starting calculator. Tarragon need full sun and soil with a pH of 6.0–7.5. Water needs are low, so water sparingly once established and never let the soil stay wet — most failures come from too much water, not too little. The watering calculator gives a starting point for your bed size. Expect 60–90 days from sowing to maturity.
Common problems and fixes
The pests most often reported on tarragon are aphids, slugs, thrips. Companions may reduce pressure, but they do not prevent them — inspect leaf undersides and new growth weekly and act while numbers are low.
| Problem | What you see | First fix |
|---|---|---|
| Aphids | Sap-sucking insects on new growth; leaves curl. | Wash off with water; encourage ladybirds. |
| Slugs | Chewed leaves and silvery trails, worst in damp weather. | Beer traps or copper tape; clear debris. |
| Thrips | Silvery streaks and distorted young leaves. | Blue sticky traps; keep plants watered. |
Aphids
Wash them off with a strong jet of water and leave ladybirds and lacewings alone to eat them. Check the undersides of young leaves, where colonies start.
Slugs
Slugs feed at night in damp weather. Clear boards, pots and debris where they hide by day, and set beer traps at soil level near the worst-hit plants.
Thrips
Thrips are tiny and hard to see; look for silvery streaking on young leaves. Blue sticky traps catch the adults, and well-watered plants cope better.
Unsure what you are seeing? Try the pest-identifier helper or the plant-disease checker. Remove badly affected leaves and rotate the Asteraceae family next year.
Frequently asked questions
What is the best companion plant for tarragon?
The most widely recommended companions are tomatoes. A tall, sun-loving neighbour for the same warm bed; plant the herb at the sunny edge so it is not shaded out, and keep spacing generous for airflow.
What should not be planted near tarragon?
Avoid other members of the Asteraceae family, including Lettuce, Artichokes, Romaine Lettuce, Iceberg Lettuce. They share the same pests and diseases as tarragon, so problems move easily between them. Rotate the family to a fresh bed each season.
Can I plant tarragon with peppers?
Yes. Peppers are on the companion list for tarragon. Another heat-lover for the same sunny bed; its upright habit leaves room at its feet for low herbs.
How far apart should tarragon and their companions be planted?
Space tarragon plants 18–24 inches apart, and put companions in the gaps, along the edges and at the ends of rows. The plant-spacing calculator works out how many plants fit your bed.
Does companion planting replace pest control?
No. It may reduce pest pressure, but it does not replace inspection, spacing, watering, rotation and good airflow. Check plants weekly and act early.