Rosemary
Salvia rosmarinus
Resinous evergreen whose scent unsettles bean beetle and carrot fly.
- Type
- Herb · Perennial
- Botanical family
- Mixed / other
- Foliage color
- Green
- Flower color
- Blue
- Sunlight
- Full sun
- Watering
- Low
- Soil
- Poor, dry, free-draining
- Feeding
- Rarely worth feeding; poor soil gives the best flavor.
- USDA zones
- 7a–10b
- Frost tolerant
- Yes
- Flowering
- April
- Pruning
- Trim lightly after flowering, and never cut back into bare wood.
- Overwintering
- Shelter it from wet cold, and grow it in a pot where the site is exposed.
- Plant out
- at the last spring frost
- First harvest
- 60 days after the last spring frost
- Harvest ends
- 14 days after the first fall frost
- Mar–Apr Bud Break
- Apr–Apr Harvest
- Apr–Oct Flowering
- Oct–Dec Growing
- Jan–Mar Growing
- Plant spacing
- 2 ft 6 in
- In-row spacing
- 23.6 in
- Between rows
- 2 ft 11 in
- Square-foot density
- Not suited to SFG
- Root system
- Woody and fibrous
- Working depth
- 12–24 in
- Can reach
- 3 ft down where the soil allows
- Spread
- 4–5 ft across, about 1.5–2× the width of the plant
- Shallowest pot
- 20 in of soil
A shallow woody framework with the fine feeding roots in the leaf litter above it. Those feeders are mostly under the outer half of the canopy rather than against the stem, which is where water and feed should go.
The habit is Rosemary’s own; the figures are what that habit usually comes to at this size, not a measurement of this species. Roots follow the soil either way: a compacted pan, a high water table or heavy clay stops them well short of any of it, and deep open ground lets them go further.
- Cats and dogs
- Confirmed safe
We say a plant is safe only where a named poison-control reference names that exact species and records it as non-toxic to both cats and dogs. Most plants are on nobody’s list, and their absence here is not a judgement about them. This is a record of what those references say, not veterinary advice, and it cannot account for your own animal, the quantity eaten, or a plant treated with anything.
We file rosemary under the current name Salvia rosmarinus; the ASPCA still files it as Rosmarinus officinalis. The same species, and the divergence is exactly why the source’s own Latin is recorded: a match on our name alone finds nothing.
- When
- Being evergreen, rosemary can be picked in any month, though flavor and oil content peak in late spring and summer on the new season's growth. Harvest in the morning once dew has lifted; go gently in winter when the plant cannot regrow.
- What to look for
- Soft, pliable new stem tips with fresh green needles — these are the most tender and aromatic. Older growth is woodier and stronger-tasting but still perfectly usable.
- How to harvest
- Snip 10–15cm tips from the soft top growth with secateurs or scissors, cutting just above a leaf junction. Never cut back into bare brown wood, as rosemary rarely regenerates from old wood; take no more than about 20 percent of the bush at once.
- How often
- Frequent light picking through the growing season acts as helpful pruning and keeps the shrub dense. Avoid hard harvesting from early autumn onward so cuts harden before frost; a mature bush supplies a household year-round.
- Storing the crop
- Fresh sprigs keep two weeks or more in the fridge in a loosely closed bag. Rosemary dries easily (hang bunches, then strip needles) and keeps its flavor well; sprigs also freeze whole, or needles can be preserved in oil or infused in vinegar.
- Rosemary beetle A small metallic green-and-purple striped beetle that grazes rosemary, lavender, sage, and thyme. Shake branches over a tray to collect adults and larvae.
- Root & crown rot Root rot in wet or heavy ground
- Frost damage Soft new growth and open flowers blackened by late frosts. Fleece on cold nights, avoid planting in frost pockets, and resist cutting damage away until frosts pass.
Sage, Thyme, Lavender, Beans
Rosemary is an evergreen shrub that can live for decades and grow waist-high.
Green-leaved herbs, like this one.
The Cottage Garden Companion — the gardener's herbarium at cottagegardencompanion.com