Record — updated 2026-07

Greek Oregano Companion Plants

Entry No. 048

Origanum vulgare subsp. hirtum · mint family family · rotation group: other

The best companion plants for greek oregano are Pepper, Rosemary, Thyme and Thyme. Avoid planting greek oregano near Basil, Mint. Of the 7 pairings recorded here, 0 are supported by published research and 5 are traditional practice with no controlled evidence behind them.

Research-backed tested in controlled research Traditional long practice, untested Not supported tested and not supported

What to plant with greek oregano

Companion plants for greek oregano — 0 research-backed, 3 traditional
Plant Claimed benefit Evidence What the evidence actually shows
Pepper Oregano is a low ground-cover partner that shares pepper's heat and drainage needs. Traditional The shared cultural requirements are real; the pest benefit is not demonstrated.
Rosemary Grows well with other Mediterranean herbs under one dry, sunny watering regime. Traditional A sound cultural grouping: both demand sharp drainage and full sun and fail in wet soil.
Thyme Shares thyme's drainage and sun requirements in a dry herb bed. Traditional Cultural compatibility only; no measured interaction.
Eggplant Oregano is said to deter flea beetles on eggplant. Not supported Falls under the aromatic-repellency belief WSU Extension reports is not borne out in field research.
Tomato Oregano repels tomato pests and improves tomato flavour. Not supported Aromatic repellency is not supported by field research, and a three-year double-blind taste test found no consistent flavour preference for companion-grown tomatoes.

What not to plant with greek oregano

Plants to keep away from greek oregano
Plant Claimed problem Evidence What the evidence actually shows
Basil Basil's high water needs conflict with oregano's demand for dry, sharply drained soil. Traditional A real cultural conflict rather than a chemical one; overwatering oregano causes root and stem rot.
Mint Mint's rhizomes overrun a shared herb bed. Traditional Follows directly from mint's documented rhizomatous spread; keep mint contained.

The honest verdict

None of the companion pairings commonly recommended for greek oregano 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 3 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: Tomato — Aromatic repellency is not supported by field research, and a three-year double-blind taste test found no consistent flavour preference for companion-grown tomatoes.; Eggplant — Falls under the aromatic-repellency belief WSU Extension reports is not borne out in field research.

Every row above links to the publication it came from. See how we grade evidence.

Other recorded effects

1

Effects that aren't about a neighbouring plant — what greek oregano does for (or to) the garden around it, and the caveats attached to the popular versions of those claims.

Recorded effects and caveats — Greek Oregano
Effect The claim Evidence What the evidence actually shows
Pollinators Oregano left to bloom is a strong nectar source for bees and predatory wasps. Traditional Flowering oregano is reliably visited by pollinators, but no trial links that to reduced pest damage on a neighbouring crop.

Growing greek oregano: the numbers

Field data — Greek Oregano
SunFull sun (6+ hours)
WaterLow once established
Spacing12 in apart · 18 in between rows · 1 per square foot
Mature sizeabout 24 in tall
Soil pH6–8
Days to maturity80–90 days
Frost toleranceHardy — takes hard frost
ContainersYes — 2 gallon minimum
Hardiness zones4–9 (perennial)
Common pestsaphids, leaf miners, spider mites
Common diseasesroot rot, fusarium wilt, botrytis

When to plant greek oregano

Zone 6b shown
J
F
M
A
M
J
J
A
S
O
N
D
Start indoors Sow / transplant outdoors Harvest

Start seeds indoors: Jan 30 – Feb 13 — 8–10 weeks before your last frost

Transplant outdoors: Apr 10 – Apr 23 — around your last frost date

Expected harvest: Jun 29 – Jul 9 — 80–90 days from planting

Those dates are for zone 6b. Get your own dates by ZIP code →

Varieties worth knowing

seeds

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 greek oregano 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:

Greek Oregano companion planting questions

What should not be planted next to greek oregano?
Basil, Mint. Basil's high water needs conflict with oregano's demand for dry, sharply drained soil. A real cultural conflict rather than a chemical one; overwatering oregano causes root and stem rot.
How far apart should greek oregano be planted?
Space greek oregano about 12 inches apart in the row, with 18 inches between rows. In a square-foot bed that works out to 1 plant per square foot.
Does companion planting with greek oregano actually work?
Partly. None of the pairings we found for greek oregano have been confirmed in controlled trials. The rest are traditional practice: plausible, harmless to try, but untested. Treat the folklore as a starting point rather than a rule, and read what the evidence says about companion planting.
When should I plant greek oregano?
Start seed indoors 8–10 weeks before your last frost. Transplant outdoors around your last frost date. In zone 6b that means roughly Apr 10 – Apr 23. Get exact dates for your ZIP code →

Sources for this record

Record compiled 2026-07. Spot an error or a study we missed? Tell us and we'll correct the entry.