Rosemary Companion Plants
Salvia rosmarinus · mint family family · rotation group: other
The best companion plants for rosemary are Thyme, Sage and Sage. Avoid planting rosemary near Mint, Basil. Of the 7 pairings recorded here, 0 are supported by published research and 4 are traditional practice with no controlled evidence behind them.
What to plant with rosemary
| Plant | Claimed benefit | Evidence | What the evidence actually shows |
|---|---|---|---|
| Sage | Mediterranean herb-bed partner with matching water and drainage needs. | Traditional | Cultural compatibility only. |
| Thyme | Shares the same lean, sharply drained, full-sun conditions. | Traditional | A genuinely useful cultural grouping: both die from overwatering rather than from cold in most gardens. |
| Bean | Rosemary is said to deter Mexican bean beetle. | Not supported | No field evidence; volatile oils disperse too quickly outdoors to protect a neighbour. |
| Cabbage | Rosemary's scent repels cabbage moths and carrot flies. | Not supported | This is the specific belief WSU Extension reports field research has not borne out for any aromatic species in an open garden. |
| Carrot | Rosemary is said to mask the scent carrot rust fly uses to find carrots. | Not supported | Scent-masking by aromatic companions is not supported by field research. |
What not to plant with rosemary
| Plant | Claimed problem | Evidence | What the evidence actually shows |
|---|---|---|---|
| Basil | Basil needs consistently moist soil that will rot rosemary roots. | Traditional | Cultural mismatch rather than chemical antagonism. |
| Mint | Mint's moisture demand and rhizomes are incompatible with rosemary's dry, lean requirements. | Traditional | A real cultural conflict: wet soil is the leading cause of rosemary death. |
The honest verdict
None of the companion pairings commonly recommended for rosemary have been confirmed in controlled trials that we could find. That does not make them harmful — it means the benefit is unproven, and you should plant for spacing, sun, and water compatibility first.
The remaining 2 pairings on this page are traditional practice. They circulate on every companion planting chart online, but we could not find controlled evidence testing them. They are not wrong so much as unverified — most cost nothing to try, and interplanting flowers and herbs has its own well-documented benefit of pulling pollinators and predatory insects into the garden.
Widely repeated, not supported: Cabbage — This is the specific belief WSU Extension reports field research has not borne out for any aromatic species in an open garden.; Bean — No field evidence; volatile oils disperse too quickly outdoors to protect a neighbour.; Carrot — Scent-masking by aromatic companions is not supported by field research.
Every row above links to the publication it came from. See how we grade evidence.
Other recorded effects
1Effects that aren't about a neighbouring plant — what rosemary does for (or to) the garden around it, and the caveats attached to the popular versions of those claims.
| Effect | The claim | Evidence | What the evidence actually shows |
|---|---|---|---|
| Pollinators | Rosemary flowers very early and provides nectar when little else is blooming. | Traditional | Observationally reliable in mild-winter regions; not quantified in a controlled trial. |
Growing rosemary: the numbers
| Sun | Full sun (6+ hours) |
|---|---|
| Water | Low once established |
| Spacing | 24 in apart · 36 in between rows · 1 per square foot |
| Mature size | about 48 in tall |
| Soil pH | 6.5–7 |
| Days to maturity | 80–100 days |
| Frost tolerance | Tender — killed by frost |
| Containers | Yes — 5 gallon minimum |
| Hardiness zones | 8–10 (perennial) |
| Common pests | spider mites, aphids, mealybugs, whiteflies, scale |
| Common diseases | root rot, botrytis, powdery mildew |
When to plant rosemary
Zone 6b shownStart seeds indoors: Jan 16 – Jan 30 — 10–12 weeks before your last frost
Transplant outdoors: Apr 24 – May 7 — 2 weeks after last frost
Expected harvest: Jul 13 – Aug 2 — 80–100 days from planting
Those dates are for zone 6b. Get your own dates by ZIP code →
Varieties worth knowing
seeds- Arp — cold-hardiest upright; reliable to zone 7a
- Madeline Hill (Hill Hardy) — improved hardiness, to about zone 7a
- Tuscan Blue — vigorous upright with strong culinary flavour
- Prostratus — trailing habit; best for containers and walls
Variety names link to seeds on Amazon. As an Amazon Associate we earn from qualifying purchases. These are the varieties named in the extension sources for this crop, not a paid placement — where a source recommended a variety for a specific reason, that reason is the note beside it.
Put it in a bed
The garden planner checks every square against this ledger as you place crops — if you drop rosemary next to something recorded as a bad neighbour, the square turns red and tells you why.
Records for the plants named above:
Same rotation group (other) — don't follow one with another:
Rosemary companion planting questions
What should not be planted next to rosemary?
How far apart should rosemary be planted?
Does companion planting with rosemary actually work?
When should I plant rosemary?
Sources for this record
- Salvia rosmarinus, NC State Extension Gardener Plant Toolbox
- Herb Garden Plants: Rosemary, Penn State Extension
- Rosemary, Rosmarinus officinalis, Wisconsin Horticulture, UW-Madison Extension
- Rosemary Key Growing Information, Johnny's Selected Seeds
Record compiled 2026-07. Spot an error or a study we missed? Tell us and we'll correct the entry.