Ozothamnus

( oh - zoh - THAM - nus )

At-A-Glance Information

This genus of evergreen shrubs and shrublets includes species which need full sun and regular water for best performance in the garden. Species are native to Australia and produce densely packed flower heads of typically white (sometimes pink or red) blooms. These shrubs make great accent plants, foundation shrubs, as specimens in mixed beds and borders, or as hedge or screening. Flowers are cultivated for use in dried and fresh flower arrangements, adding wonderful fragrance, form, and filler for bouquets. Take care when planting these shrubs in the garden, as plant parts can be toxic to humans and pets if ingested.

Ozothamnus Species and Varietals

The genus Ozothamnus includes around 60 species and is a member of the plant family Asteraceae. Plants in this genus are closely related to those in Helichrysum. The genus name is derived from the Greek words ozos- (branch) and -thamnos (shrub). They typically do well in USDA hardiness zones 9a-11 or Sunset growing zones 14-24. To find your zone, click here: Zone Map.

Ozothamnus alpinus (Alpine Everlasting)
These plants are endemic to southeastern Australia, and typically reaches between 2.5 and 3 feet tall. Branches are covered in hairs that turn grey as they age, and flowers are white to yellow, surrounded by reddish-orange outer bracts. In the plant's native range, flowering occurs from February through March.

Ozothamnus cuneifolius (Wedge-Leaf Everlasting, Wedge Everlasting)
These plants are native to the forests of Australia, and reach up to 10 feet tall when mature. Leaves are green and have undersides covered with fine white hairs. Flowers are white, and bloom from November through January in the plant's native range.

Ozothamnus cupressoides (Scaly Everlasting, Lattice Everlasting, Kerosene Bush)
These shrubs reach between 1.5 and 3.3 feet tall when mature, and produce whitish tomentose branches. Leaves are scale-like and small. They are green on their upper surfaces and white and hairy underneath. Flower heads appear in dense clusters in summer and fall, and are white.

Ozothamnus diosmifolius (Rice Flower, White Dogwood, Pill Flower, Sago Bush, Sago Flower)
These plants are commonly grown for their flowering heads, which are cut off of shrubs and used in fresh floral arrangements. Individual plants reach up to 7 feet tall, and have branches that are rough and densely covered with short hairs. Flowers are white with some pinkish coloration thanks to their colorful bracts. Cultivars include 'Pink' (with pink flowering heads), and 'Radiance' (with profuse stark-white blooms).

Ozothamnus leptophyllus (Tauhinu, Cottonwood, Silver Cottonwood, Silver Heather)
These plants reach up to 6 feet tall when mature, and are common plants in coastal farmlands in New Zealand. It forms a yellow-green to greyish bushy shrub with tomentose branches and leaf undersides. Young leaves are slightly sticky. Flowers are typically white, but can be blushed with shades of pink or red.

Ozothamnus rosmarinifolius (Rosemary Everlasting, Rice Flower, Cottonwood, Sea Rosemary)
These shrubs are native to Australia, and reach 6-10 feet tall and 3-5 feet wide (in 5-10 years' time) with a dense upright habit. Leaves are slender and dark green, resembling
Rosemary (hence the common name), and flowers are small and white, blooming from red buds beginning in late summertime. The plant has a pleasant fragrance, especially when the weather is warm. Cultivar 'Silver Jubilee' has silver-toned foliage. This species is considered invasive in California (United States).

Ozothamnus secundiflorus (Cascade Everlasting)
These aromatic shrubs are endemic to Australia, and reach between 1.5 and 6 feet tall when mature. They have dark green to greyish foliage with tomentose undersides. Flower heads are white, and appear in dense clusters in December through February in the plant's native range.

Caring for ozothamnus

Plant Ozomthamnus shrubs in a space in the landscape that receives full sun; ideally, they appreciate between 6 and 8 hours of sun each day for the best blooms. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.1 and 6.5 (slightly acidic). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants are considered drought tolerant, able to get by on rainwater alone for much of the year with supplemental irrigation during extended periods of drought. Allow soil to dry out between waterings.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season. Deadhead spent flowers as they fade and after the blooming season is over, shape the shrub, pruning back 20 to 30 percent of the overall foliage. These shrubs flower on new wood, so the best time to prune is in late summer or fall. Ozothamnus shrubs are fast-growing, short-lived perennial plants, and can last for a few decades in the garden before needing to be replaced.

Caring for Ozothamnus in Containers
Ozothamnus shrubs are wonderful in the ground, but can also be grown in containers. Choose a container that is at least a few inches wider and deeper than the nursery pot or root ball. Ensure that the pot has adequate drainage holes on the bottom to allow for excess water to flow away. Fill with a well-draining potting mix amended with organic material and perlite, and top with a layer of mulch to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water regularly as the plant establishes itself in its new home. Once established, waterings can be lessened. Ozothamnus plants grown in containers will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top few inches of soil feels dry to the touch. Prune to remove dead, damaged, or diseased foliage at any time during the growing season. Every few years, check the bottom of the pot to ensure that the plant is not outgrowing its root space. If roots are growing through the drainage holes in the bottom of the container, it is a good indication that it needs to be potted up; choose a slightly larger container and repot. Ozothamnus plants typically need to be repotted every two to three years.

Harvesting Ozothamnus
Ozothamnus, widely known as Rice Flower in the cut flower industry, is typically available from late winter through spring. They are prized filler flowers, with their dense, spherical clusters of tiny rice-like buds and long vase life, and are heavily used to add delicate texture and volume. They emit a spicy, honey-like fragrance, especially when warm. The species most commonly grown for its cut flowers is Ozothamnus diosmifolius. The flower heads are ready to be harvested when flower buds are plump and colored but before they fully open up. In the morning, after dew has dried but before the heat of the day sets in, set out to cut stems. Using clean, sharp shears, sever the stem just above a node. Strip all leaves that will sit below the water line, and then drop the harvested stems into a bucket of cool water. Ozothamnus stems have a vase life of between 7 and 14 days.

Ozothamnus flowering stems can also be dried for use in crafts. After harvesting, remove all foliage and hang bunches of 5-8 flowering stems upside-down in a cool, dark, dry area. As they are drying, keep them away from sunlight, high heat, and excess moisture. Leave the stems to air dry for 2 to 4 weeks' time. The dried flower stems can be arranged in dried bouquets, used in centerpieces or wreaths, or the individual blooms can be harvested and used as a 'less mess' alternative to rice or confetti.

Propagation

The simplest way to propagate Rosemary Everlasting is through taking cuttings in spring or early summertime. To propagate your shrub, follow the instructions below.

Propagating Ozothamnus by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.