Rosemary
Rosmarinus officinalis
Lamiaceae · mint family
- Matures
- 80–100 days
- Harvest
- Continuous · Perennial
- Sun
- 6–8+ hrs
- Spacing
- 24–36 in
Planting window
When to sow, by microclimate — foggier blocks run a different calendar than sunnier ones.
| Jan | Feb | Mar | Apr | May | Jun | |
|---|---|---|---|---|---|---|
| Foggy | ◐ | ● | ● | ● | ● | |
| Sunny | ◐ | ● | ● | ● | ● | ● |
| Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|
| Foggy | ● | ● | ● | ● | ◐ | |
| Sunny | ● | ● | ● | ● | ● | ◐ |
Sunlight
How well it does at each level of direct sun per day.
Soil depth
Root room it needs — useful for sizing raised beds and containers.
Spacing
Room each plant needs — along the row and between rows — for sizing beds.
- In-row
- 24–36 in
- Between rows
- 24–36 in
Growth habit
The shape it makes in the bed and how tall it gets — what tells you whether to give it a trellis, a stake, or just room.
- Habit
- Upright
- Mature height
- 4–5 ft
Stands on its own; the tallest types appreciate a stake in wind.
How to start it
Sow it where it grows, or raise it under cover and set it out — and how far ahead to start the seedlings if it's the latter.
- Usually
- Transplant
Goes in as a rooted start, cutting, or division rather than raised from seed.
Getting started
How it goes in the ground — how deep to sow or set it, and the soil temperature it needs to wake up. The cold-soil floor is the real limiter for direct-sowing in a foggy SF spring.
- Started from
- From seed
- Ideal soil temp
- 60°F
- Sow depth
- 0–0.125 in
- Time to emerge
- 12–28 days
Germinates between 55–65°F; happiest around 60°F.
Pests & diseases
What tends to trouble this crop — what it is, what you'll see, and what to do about it, least-toxic first.
Our sources document no specific pests or diseases for this crop; it's generally grown without major pest trouble in home gardens.
Sources
Every figure above is backed by these.
- UC Master Gardeners, Marin Countybacks plantingWindow, sunlight, startMethod · UC Marin MG Rosemary grow sheet (coastal Bay Area): 'Best planted in spring through early summer, but in Marin's temperate climate it can be planted anytime' (wide set-out window — rosemary is the hardiest, most coastal-tolerant of these Mediterranean herbs, so its month map is broader than thyme/sage/oregano and stays open through foggy summer). 'Requires full sun' (sunlight). Start method: UC Marin MG rosemary: 'Transplant starts or propagate by cutting.' The page gives no seed route at all, so rosemary goes in as an acquired plant and carries no under-cover lead time.
- UC Integrated Pest Management (UC IPM)backs plantingWindow, sunlight, inRowSpacing, rowSpacing · UC Statewide IPM 'Cultural Tips for Growing Rosemary': North/North Coast planting window 'January-December' and 'Transplant in spring without concern for frost, as plants can survive temperatures as low as 15F' (supports the broad, nearly year-round SF window; deep-winter wet months held to maybe/no as a practical establishment caution). 'Rosemary grows best if the plant receives full sun to partial shade (at least 4 to 6 hours a day)' (sunlight; 4-6 = maybe). 'Plant rosemary 2 to 3 feet apart in landscapes' (inRowSpacing 24-36). Between-row spacing is taken equal to the in-row figure: this crop is spaced about equally in all directions and the source gives a single spacing, not a distinct row width.
- Johnny's Selected Seedsbacks daysToMaturity · Rosemary (product 932) spec from a horticulture-staffed seed house: days to maturity '80-100 stem tips; 120-180 bunches'. Used the stem-tips figure (80-100) as the first-usable-harvest window, consistent with the other perennial herbs; full bunches take 120-180. Rosemary germinates slowly (14-21 days) and is often grown from cuttings, so treat this as approximate.
- NC State Extension — Plant Toolboxbacks sunlight, soilDepth, inRowSpacing, lifecycle, harvestStyle, growthHabit · Salvia rosmarinus entry: 'Full sun (6 or more hours of direct sunlight a day)' (corroborates full-sun bands). 'Height 4-5 ft, Width 3-4 ft', 'generally erect and rounded' woody shrub, 'Available Space To Plant: 3 feet-6 feet' (corroborates the wider 24-36 in in-row spacing). growthHabit: Height '4 ft. 0 in. - 5 ft. 0 in.' -> 48-60 in; 'generally erect and rounded' woody shrub (self-supporting, distinctly vertical) -> upright. Soil depth assigned moderate (6-10 in = maybe, deeper bands = yes): though it is a large shrub, rosemary is a drought-tolerant Mediterranean plant of shallow rocky soils and common in containers, so sharp drainage — not depth — is the real constraint. No numeric rooting depth exists. Non-CA extension, agronomy only. Habit and harvest: perennial, continuous — a woody evergreen perennial shrub whose sprigs are cut repeatedly through the season.
- UMass Extensionbacks germination · UMass Extension rosemary: optimum germination soil temp 60°F, slow/erratic 12–28 days; 55/65 band around the cited optimum.
- USDA GRIN Taxonomybacks botany · GRIN has not adopted the transfer to Salvia rosmarinus; Rosmarinus officinalis is its accepted name.
- UC Master Gardeners, Alameda Countybacks plantingDepth · No per-crop depth published (RHS/NC State/UC Marin: rosemary is slow from seed, usually grown from cuttings). UC MG general rule: 'Seeding depth is generally never more than 2-3 times the seed diameter, and often shallower is better' - rosemary's tiny seed also needs light, so surface-sown to ~1/8 in.