Grow coastal rosemary in full sun, on soil that drains, and water it through the first season. Coastal rosemary is Westringia, not the rosemary you cook with.
Give it full sun, soil that drains, and water until it is established
| Factor | Recommended | Avoid |
|---|---|---|
| Light | Full sun for a tight mound and the most flowers | Do not tuck it in deep shade, where the shrub opens up and blooms less |
| Soil | Sand or loam that drains; a coastal or gravel bed is fine | Do not plant it in a hole that stays wet through winter |
| Water | Water a new shrub through the first season, then only in a long dry spell; inland gardens may want one deep soak in summer | Do not keep the soil wet once the plant is established |
| Kind | Coastal rosemary for a 4-to-6-foot hedge or mound; Mundi for a 1-to-2-foot carpet | Do not keep Mundi in a wet hole because it is shorter |
| Salt | Coastal beds, wind, and salt spray are fine once the hole drains | Do not treat salt tolerance as a reason to skip drainage |
Coastal rosemary wants full sun and a hole that still drains. Water a new shrub through the first season, then ease off. An established plant takes missed water better than a wet winter hole, and it keeps better color with an occasional soak in a hot inland summer. [1] coastal rosemary is Westringia fruticosa, a 4-to-6-foot evergreen that is often wider than it is tall. Mundi is the low carpet form, about 1 to 2 feet tall and 4 to 6 feet wide. Both want the same sun and the same dry interval. [2]
- Choose full sun and soil that drains. A wet pocket is the usual reason the shrub dies back from the ground up.
- Water a new shrub until it is established. After that, water only in a long dry spell.
- On a hot inland site, give an established plant a deep soak now and then in summer so the foliage stays dense.
Does coastal rosemary need full sun?
Yes. Full sun gives you the tightest mound and the most flowers. Light shade is tolerated inland, but the shrub opens up in deep shade.
How often should I water coastal rosemary?
Water a new shrub through the first season, then only in a long dry spell. Inland gardens may want one deep soak in summer.
Does salt spray bother it?
No. Established shrubs take wind and salt spray, as long as the hole still drains.
Plant in spring, with room for a hedge or a low carpet
Plant in spring, or in fall where winters stay mild on the coast. Set the root ball even with the surrounding soil, and leave room so a hedge can close without sitting in a wet pocket. [3]
- Dig a hole as deep as the root ball and about twice as wide. Loosen circling roots.
- Set the top of the root ball even with the surrounding soil. Do not bury the stems.
- Leave about 2 and a half to 4 feet for a low hedge of coastal rosemary. Set Mundi closer, so the carpet can meet.
- Water in, then keep mulch a few inches off the stems so the crown stays dry.
How far apart do I plant coastal rosemary?
Leave about 2 and a half to 4 feet for a low hedge. Set Mundi closer, so the carpet can close. Do not pack them into a wet hole.
Clip lightly after the flowers, and do not cut into bare wood
Light clipping keeps the mound dense. Wait until the main flush of white flowers has finished, then take it back to size. If you skip clipping for years and then cut into old leafless wood, the stems often will not reshoot. [4]
- Wait until the main flower flush has finished, or clip during active growth in a mild climate.
- Take only leafy growth. Shape a hedge with regular light cuts, not one hard renovation.
- Do not cut into old bare wood, and do not make a heavy cut late in a climate that still gets a hard freeze.
When do I prune coastal rosemary?
After the main flowers finish, or during active growth in a mild climate. Clip lightly and often. Do not cut into bare wood.
How to take a cutting
Nurseries start named kinds from cuttings, and a home cutting is a reliable way to copy Mundi or a hedge plant you already like. Seed is slower, and a named kind will not come true.
- Take a leafy cutting below a node during the growing season.
- Strip the leaves from the lower part of the stem.
- Push the stripped end into a mix that drains, with plenty of perlite.
- Keep the mix barely moist, in bright light out of hot direct sun, until roots form. That often takes about two months in warm weather.
- Pot the rooted cutting, then plant it out once it is growing.
Can I grow coastal rosemary from a cutting?
Yes. Take a leafy cutting in the growing season, strip the lower leaves, and stick it in a mix that drains. Named kinds such as Mundi do not come true from seed.
Not culinary rosemary
A tag that says rosemary may be the kitchen herb, which is Salvia rosmarinus. That plant is grown for cooking. Coastal rosemary is Westringia, an Australian evergreen grown for a hedge or a carpet. The leaves look similar, and they are in the same mint family, but you do not cook with this shrub. See How to Grow Sage for culinary rosemary.
Is coastal rosemary the same as rosemary?
No. Rosemary is Salvia rosmarinus, the kitchen herb. Coastal rosemary is Westringia, an ornamental hedge or carpet. Do not cook with it.
Set coastal rosemary in full sun, on soil that drains, water it through the first season, clip lightly, and leave culinary rosemary to the sage bed.
FAQ
Can I grow coastal rosemary in a pot?
Yes, for a few seasons in a large pot with a drainage hole. It is still an outdoor evergreen. Move a full-size shrub into the ground before it outgrows the pot.
Do you list Grey Box or Wynyabbie Gem?
This catalog holds coastal rosemary and Mundi. Grey Box, Morning Light, Smokey, and Wynyabbie Gem are extra names, not extra cards here.
Will Mundi come true from seed?
No. Mundi is a named selection. Start it from a cutting if you want the same low carpet. Seedlings vary.
Recommended plants
References
- [1] San Marcos Growers -
https://smgrowers.com/products/plants/plantdisplay.asp?plant_id=1603 - [2] UC Marin Master Gardeners -
https://www.ucanr.edu/site/uc-marin-master-gardeners/article/westringia-every-garden - [3] Gardenia -
https://www.gardenia.net/plant/westringia-fruticosa-coast-rosemary-grow-care-guide - [4] Australian Plants Society NSW -
https://resources.austplants.com.au/plant/westringia-fruticosa/
More first-season notes by plant are gathered in How to Grow Guides.
Updated: Reviewed by Bosquelle Editors