Coast rosemary is a dense evergreen shrub that is native to Australia. The dark gray-green leaves look similar to rosemary needles, hence the common name. This tough plant stands strong in drought, heat, and salt spray. Although some of the wild forms of this plant have a wayward, unkept look, cultivated forms of coast rosemary are more compact, set brilliant spring flowers, and do well with shearing. Simply prune the evergreens into a pleasing shape and enjoy their easy-care ways throughout the garden.
Coast Rosemary Overview
Where to Plant Coast Rosemary
Plant coast rosemary in a location with ample sun. Well-drained soil is a must. In terms of pH, coast rosemary is adaptable to acidic or neutral soil.
There are multiple landscape uses for this tough plant. It is excellent for stabilizing a slope or in a rock garden. Wherever you plant it, choose a location that gives it space, both for its roots and its branches.
How and When to Plant Coast Rosemary
Plant coast rosemary in the early spring to give it all season to get established. Dig a hole at least twice the size of the root ball and place the plant in the hole. Backfill it with the original soil and gently tamp it down. Water it immediately after planting and continue to water it regularly during the first growing season to encourage a strong root system.
Space the plants 3 to 5 feet apart.
Coast Rosemary Care Tips
Light
Coast rosemary thrives in bright sun, though it will tolerate part shade.
Soil and Water
Coast rosemary is easy-to-grow in average, sandy, or well-drained soil with a pH between 4.5 and 7.0.
Water it for the first season after planting. A layer of coarse mulch over the root zone helps conserve soil moisture. Once established, it can handle drought, however, it maintains better color and the shrub remains fuller if it gets occasional water in the spring and summer.
Temperature and Humidity
Although coast rosemary can withstand some winter cold, it is not suitable to be grown below zone 9. It is well adapted to hot, dry climates and can withstand some humidity.
Fertilizer
While fertilizer is not essential, applying a balanced, slow-release fertilizer in the spring encourages blooming. For the amount to use, follow product label directions.
Pruning
Coast rosemary requires little pruning, especially the groundcover varieties. To give the upright varieties a tidier look, you can prune them lightly in the spring or early summer after the bloom. Make sure to remove primarily leafy growth and not the woody stems.
Potting and Repotting Coast Rosemary
Coast rosemary can be grown in containers. Choose a pot that is about twice the diameter of the root ball to allow for growth. Fill it with a well-draining potting mix.
Water well after planting and keep the soil lightly moist at all times, as coast rosemary needs more water in pots than in garden soil. Repot it to a larger pot with fresh soil when the roots have filled the container after a couple of years.
Pests and Problems
Coast rosemary is fairly resistant to any pest or disease. Yellowing of the foliage may indicate too much phosphorus in the soil. The other potential problem is too much water from overwatering or planting coast rosemary in poorly draining, heavy clay soil.
How to Propagate Coast Rosemary
You can propagate coast rosemary from a stem cutting in the spring or early summer. Take a 6-inch healthy cutting and remove the lower leaves, Dip the cut end in rooting hormone powder and insert it into a 4-inch pot filled with damp potting mix. Place it in a location with bright light but away from direct sunlight. Keep it evenly moist at all times. After two months, the cutting should have rooted. Let it grow into a vigorous little plant before transplanting it in the garden or in a larger pot.
Types of Coast Rosemary
Plant breeders have introduced several new varieties of coast rosemary to the market, including small, ground-hugging varieties and kinds that sport striking blue-purple flowers. They are all rugged, easy to grow, and tolerate dry soil and high temperatures.
Mundi Coast Rosemary
Westringia fruticosa ‘Mundi’ is a low-growing variety with dark, gray-green leaves and small, white, star-shaped flowers. It grows 1 to 2 feet tall and spreads 4 to 5 feet. Zone 9-10
Smokey Coast Rosemary
This is a cultivar whose leaves have cream-colored edges. The flowers are white to pale purple. Westringia fruticosa ‘Smokey’ is a compact shrub that grows 4 to 6 feet tall and wide. Zone 9-11
Blue Gem Coast Rosemary
Another compact variety, Westringia fruticosa ‘Blue Gem’ has olive-green leaves on dark maroon-brown stems. The flowers are a vibrant bluish purple. It grows 4 to 6 feet tall and 3 to 4 feet wide. Zone 9-10
Coast Rosemary Companion Plants
Aloe Vera
Aloe vera is an eye-catching perennial that displays lance-shape succulent leaves decorated with white spots and edged with small whitish teeth. Native to hot, dry regions of Africa, aloe perennial prefers frost-free, sunny, well-drained sites where the night temperature never dips below 50 degrees F. Zone 10-11
Yucca
Just like coast rosemary, yucca needs a full-sun garden and can stand up to some serious drought. Not only do these plants work well in a dry garden as an architectural accent, but they also make a prized container plant. The leaves come in a variety of colors, most often a silvery green. You can also find them in variegated varieties with gold, green, cream, blue, and even pink, in the right season. Zone 4-10
Perennial Salvia
Another member of the mint family, perennial salvia blooms for a long period of time in a wide spectrum of colors. The colors of salvias are diverse, as are the overall plant habits, which can vary greatly from short, low-growing plants to tall, sprawling plants. Zone 3-10
Frequently Asked Questions
- Is coast rosemary edible?Although coast rosemary and culinary rosemary are both members of the mint family, coast rosemary is not edible.
Although coast rosemary and culinary rosemary are both members of the mint family, coast rosemary is not edible.
- Does coast rosemary have a strong scent?The leaves are not nearly as strongly scented as culinary rosemary, and they don't have the same aroma. The flowers, on the other hand, are fragrant.
The leaves are not nearly as strongly scented as culinary rosemary, and they don't have the same aroma. The flowers, on the other hand, are fragrant.