Leptospermum

( lep - toh - SPERM - um )

At-A-Glance Information

This genus of evergreen shrubs or trees needs full sun and little to moderate water. They are casual-looking plants have small leaves and produce tiny blooms along branches. Flowers are typically white, red or pink and petals surround a central cone that matures to a woody seed capsule. They are native to New Zealand and Australia and are commonly called Tea Tree because leaves steeped in boiling water was touted as a remedy and preventative for scurvy for early European settlers. Plants in this genus are highly fragrant, with an aroma that is a blend of Citronella and Lemon. Use Leptospermum shrubs or trees in the landscape as a structural specimen plant, informal hedge, windbreak privacy screen, or as erosion control in sloped areas. They are also perfect large shrubs for pollinator gardens.

Leptospermum Species and Varietals

The genus Leptospermum is a member of the plant family Myrtaceae, and includes around 100 species. The genus is currently being reclassified into the genus Gaudium. Species in this genus are related to Bottlebrush and Metrosideros. Tee Tree Oil is made from the leaves of Melaleuca alternifolia, a species of another related genus. The genus was first formally described in 1776 by German father-son botanist team Johann Reingold Forster and Johann Georg Adam Forster. Tea Tree grows best in USDA hardiness zones 9-11 or Sunset growing zones 14-24, though this varies somewhat depending on the species. For more information, see the following descriptions. To find your zone, click here: Zone Map.

Leptospermum arachnoides (Spidery Tea-Tree, Stiff Tea-Tree)
This species is native to the eastern coast of Australia, and has rough bark and green foliage. These low, spreading shrubs can reach up to 3 to 6.5 feet tall and 5 feet wide at maturity. Flowers are white, and have many protruding stamens. Fruits that follow blooms are hairy. Spidery Tea Tree grows well in USDA zones 9-11.

Leptospermum laevigatum (Australian Tee Tree, Coast Tea Tree, Coastal Tea Tree)
This species grows best in USDA hardiness zones 8-11 or Sunset growing zones 14-24, H1 and H2 and can be grown as either a large shrub or a small tree. It reaches 10-30 feet tall and just as wide, with gray-green leaves and white to pink flowers that bloom in springtime. Trunks twist and curve gracefully when mature, and branches carry canopies of foliage, providing good shade. This species is considered highly invasive in California, South Africa, and regions of Australia outside of its native area.

'Compactum'
Good for low hedges, containers, or smaller gardens. To 5-8 feet tall.

'Flamingo' ('Cranbourne')
Variegated foliage on a 5-6 foot tall shrub.

'Reevesii'
Dense, rounded shrub to 4-6 feet tall and 6-8 feet wide.

Leptospermum macrocarpum (Leptospermum nitidum 'Macrocarpum') (Large-Fruited Tea Tree)
Gets to 3-15 feet tall and wide at maturity, and has tiny reddish leaves that mature to purple-bronze. Flowers bloom in springtime and are chartreuse-yellow with a green center. Cultivars include 'Dark Shadows' (pictured, to 15 feet tall and 20 feet wide with burgundy-flushed leaves), and 'Copper Sheen' (with rich copper-purple new foliage that matures to deep green to 6-10 feet tall). This species is considered invasive in Hawai'i.

Leptospermum petersonii (Lemon-Scented Tea Tree)
This species reaches up to between 9 and 20 feet tall and 6 to 15 feet wide, with an open erect habit. Branchlets are weeping. Green leaves give off a lemony scent when bruised and are used to make tea. Inconspicuous flowers are white. Cultivars include 'Little Lemon Scents' (5-6.5 feet tall), 'Lemon Lime n Bitters' (pictured, to 1.5 feet tall and wide with bronze, orange, green, and pink new growth), and 'Lemon Hedge' (with upright, dense habit perfect for formal hedging, to 8-10 feet tall). Lemon-Scented Tea Tree is considered invasive in Hawai'i, non-native regions of Australia, and New Zealand.

Leptospermum polygalifolium (Tantoon, Jellybush, Yellow Tea Tree, Lemon-Scented Tea Tree)
This species is a bit wide-ranging in appearance; it can grow to between 3 and 18 feet in height and 1.5 to 9 feet in width, with either an upright or spreading habit. Its form will depend on its surroundings and climate. Leaves are deep green and narrow, and flowers are profuse in spring and summer. Blooms are white and smell like honey, and make for attractive additions to cut flower arrangements. This species is considered invasive in Hawaii (particularly the island of Oahu). Cultivars are listed and described below:

'Bush Bronze' (Copper Glow)
Red-bronze new foliage; to 3-4 feet tall.

'Pacific Beauty'
Light green leaves on a shrub with cascading branches. To 5-6.5 feet tall.

'Pink Jellybush'
Early flowering with pink blooms, to

'Yarra River' ('Red Spire')
To 25 feet tall with burgundy-red leaves and weeping branches.

Leptospermum rotundifolium (Round Leaf Tea Tree, Round-Leaved Tea Tree)
To 6 feet tall and just a little wider, this species has an arching, spreading habit. Round, tiny green leaves and profuse lavender-pink flowers cover this shrub in springtime. Somewhat short flowering period. Cultivars include 'Manning's Choice' (fast-growing to 4-6 feet tall and 6-8 feet wide), 'Lavender Queen' (pictured, with larger, deeper lavender-pink blooms, great for cut flowers), and 'Julie Ann' (prostrate form to 1 foot tall and 5 feet across with pale pink flowers).

Leptospermum scoparium (New Zealand Tea Tree, Mānuka, Broom Tea Tree)
This species of Tea Tree grows well in USDA hardiness zones 9-11 or Sunset growing zones 14-24, H1 and H2 and has showy single or double blooms in springtime and summer in white, pink or red. Leaves are closely set on branches and are needle-like. Great as container plants. Cultivars are listed and described below.

'Apple Blossom'
This plant has an upright growing habit to 8 feet tall and wide. Double flowers are pale pink and age to white, leaves tinge pink in fall.

'Burgundy Queen'
This plant has an upright, dense habit to 12 feet tall and 10 feet wide, with double flowers in deep burgundy. Fall foliage is burgundy.

'Crimson Glory'
To 6-7 feet tall and just as wide. Foliage is bronzey and double flowers are crimson.

'Gaiety Girl'
Slow grower to 5 feet tall and 4 feet wide. Leaves are flushed red, and double flowers are lilac-pink.

'Helene Strybing'
Reaches 6-10 feet tall and wide with an open, pleasing habit. Single flowers are a deep pink.

'Horizontalis'
Fast grower to 3-4 feet tall and 12 feet wide. Branches are horizontal and branchlets droop off of them. Flowers are white and single. Great as a bank cover.

'Pink Cascade'
This plant reaches a foot tall and 3-4 feet wide, with single pink flowers. Branches take a weeping habit; this variety is great for spilling over walls and among rocks.

'Pink Pearl'
6-10 feet tall and 5-8 feet wide. Buds are pale pink and open to reveal double blush pink to white flowers.

'Ruby Glow'
Compact, upright grower to 6-8 feet tall and 4-5 feet wide. Foliage is dark and flowers are double red. The entire shrub looks red when it is in bloom.

'Silver and Rose'
Profuse rose-pink flowers with green centers and bright gray-green foliage on a 4-5 foot plant.

'Snow White'
Spreading, compact grower to 2-4 feet tall and 4-5 feet wide. Double flowers are white with green centers.

Caring for Leptospermum

Leptospermum, or Tea Tree, plants are typically purchased as specimens from a reputable nursery. Most are either grown from seed or cuttings, and are typically not grafted. These plants should be installed in a space that receives full sun; ideally, between 6 and 8 hours each day. They can take late afternoon shade in warmer climates. Space shrubs 3-5 feet apart for a dense hedge. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 5.5 and 7.0 (slightly acidic to neutral). 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 for their first year in the ground. Once established, Leptospermum plants only need occasional water and are considered drought-tolerant. Make sure there is no standing water at the roots.

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 should be done immediately after its primary spring flowering to maintain shape, encourage bushier growth, and promote the following year's blooms. Avoid cutting into old, bare wood as it will most likely not re-sprout. These shrubs can be thinned out to create a more attractive habit, but otherwise leave them alone as far as pruning is concerned. They have an attractive natural habit. Leptospermum trees and shrubs are long-lived, surviving in the landscape for 20 to 50 years or more if cared for properly.

Caring for Leptospermum in Containers
These shrubs and trees 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. At maturity, most full-size Leptospermum plants will need larger 10 to 15 gallon pots to allow for healthy root growth. 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. Leptospermum 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.

Harvesting Leptospermum
Leptospermum plants are harvested for their beautiful stems of long-lasting flowers as well as their leaves for use in teas. The foliage is very rich in essential oils and fragrant, with a herbal citrus (sometimes a bit camphoraceous and woody). Cut flowers are typically harvested when these plants are in bloom in late winter, spring, and early summer. Wait to harvest branches until all buds are fully colored and 30% to 50% of the flowers are open. Avoid branches that are showing signs of wilting or mildew. The best time of the day to harvest cut flowers is in the morning, just after dew has dried but before the heat of the day sets in. Using clean, sharp shears, cut the branch at an angle, remove foliage towards the base, and drop it into a bucket of cool water. They have a vase life of between 3 and 12 days.

Harvesting Leptospermum leaves for use in tea involves clipping the tender, aromatic shoot tips of established plants. The best time of the day to harvest is in the morning, after the dew has dried but before the heat of the day sets in. If handling large quantities, make sure to wear gloves, as the essential oils and resinous leaves can be sticky. Using clean, sharp shears, locate new growth and snip off the last 2-3 inches of the tip. Older leaves tend to be leathery and do not have the same flavor. Bundle the cut stems together and hang them upside down, or spread the cuttings in a single layer on a screen or drying tray. Place them in a cool, dark area with good ventilation. Do not use ovens or dehydrators for Leptospermum leaves, as this will destroy and evaporate the essential oils in the leaves. After one or two weeks, the stems should snap easily when bent. At this time, store the whole leaves in airtight containers out of direct sunlight to maintain their aromatic properties.

Disclaimer: Information contained on this website is strictly and categorically intended as a reference to be used in conjunction with experts in your area. Foraging and consumption of plant parts should never begin without the guidance and approval of a local plant specialist. The providers of this website accept no liability for the use or misuse of information contained in this website.

Propagation

Leptospermum can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your shrub, follow the instructions below:

Propagating Leptospermum 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.

Propagating Leptospermum by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination 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.
Harvest your seeds. The seed pods are pretty easy to spot, they're round and sit on the branches, left behind after flowers have faded (they look a little like buttons). Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will begin to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-28 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. 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 (after the danger of frost has passed), when you can transplant it to its new home.

Leptospermum seed pods are round and look like little buttons.

Leptospermum seeds are released from the seed pods when they have dried and begun to split open, as in the photo above.

Problems and Pests

Certain species are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Leptospermum shrubs are relatively pest and disease-resistant. For information on commonly encountered pests and diseases in the home garden, consult the following pages:

Pests & Pest Management

Plant Issues