How to Grow and Care for Eucalyptus

You might be most familiar with eucalyptus plants (Eucalyptus cinerea) as a favorite food of the koala. This evergreen tree can grow to nearly 60 feet high in its natural Australian environment. But when planting eucalyptus in home gardens, it usually remains small at around 6 to 10 feet high. It features reddish-brown bark that peels on the smaller branches. The leaves are a silvery to blue-green color, and they give off the plant’s distinct menthol-like fragrance when bruised.

Eucalyptus trees are best planted in the spring. These trees generally do not need any staking or other support structure on which to grow and have a fast growth rate and can gain several feet per year. It’s important to note that the bark, leaves, and sap of eucalyptus are toxic both to humans and pets.12

Common Name	Eucalyptus, silver dollar tree, argyle apple
Botanical Name	Eucalyptus cinerea
Family	Myrtaceae
Plant Type	Tree
Mature Size	6–53 ft. tall, 2–15 ft. wide
Sun Exposure	Full
Soil Type	Well-drained
Soil pH	Acidic, neutral
Bloom Time	Summer
Flower Color	White, red
Hardiness Zones	8–11 (USDA)
Native Area	Australia
Toxicity	Toxic to people, toxic to pets34

Eucalyptus Plant Care

Here are the main care requirements for growing eucalyptus:

• Plant in well-draining soil with full sun exposure.
• Plant in a location with enough space to accommodate the tree’s full height and spread. (Multiple eucalyptus trees should be spaced at least 8 feet apart).
• Prefers warm temperatures.
• Harvest mature leaves and branches later in the growing season.

 

 

 

Light

Eucalyptus likes a lot of light, so place your plant somewhere that receives at least six hours of direct sunlight daily. Likewise, eucalyptus plants grown indoors should be kept near a bright window, preferably one that faces south.

Soil

Eucalyptus can tolerate most soil types, but it needs soil with good drainage. For container plants, use a well-draining potting mix. A slightly acidic to neutral soil pH is best.

Water

Eucalyptus is somewhat drought-tolerant once it’s established. However, long periods of dryness may cause it to drop leaves. A good rule of thumb is to water when you can stick your finger into the soil and feel dryness at your fingertip.

Temperature and Humidity

Eucalyptus prefers warm temperatures between roughly 65°F and 75°F, and it likes a moderate humidity level. It cannot survive prolonged exposure to temperatures below 50°F. So if you’re growing your plant in a container, bring it indoors when you expect chilly temperatures.

Fertilizer

If you’re growing your plant in the ground, it typically won’t need fertilizer. However, container plants will deplete their nutrients more quickly. So fertilize them with a low-nitrogen houseplant fertilizer throughout the growing season, following label instructions.

Types of Eucalyptus

In addition to Eucalyptus cinerea, there are hundreds of other eucalyptus species. They include:

• Eucalyptus globulus: Known as blue gum, this species features smooth bark and is particularly adaptable to a variety of growing conditions.
• Eucalyptus gunnii: Commonly referred to as cider gum, this species has better cold tolerance than most other eucalyptus species.
• Eucalyptus platypus: Commonly called moort, this is an especially hardy species that can tolerate heavy soils, cold, and drought.

Pruning

Eucalyptus trees generally don’t need much pruning. However, you can prune overgrown, broken, or misshapen branches to keep the plant looking attractive. The best time to do so is in the summer, but avoid pruning during very humid weather.

Propagating Eucalyptus

Eucalyptus trees are most commonly grown from purchased seeds or nursery plants, but they can also be propagated via cuttings. The best time to take cuttings is when a tree is between 2 and 12 months old; rooting mature stems is difficult. Aim to take your cuttings in the late summer. Here’s how to grow eucalyptus from cuttings:

1. Fill a small pot with a 3-1 mixture of composted tree bark and perlite, and add a slow-release fertilizer. Moisten the soil.
2. Cut a stem that’s around 5 inches long with four to eight leaves. Cut just above a leaf node.
3. Remove the leaves on the lower half of the cutting.
4. Dip the cut end in a rooting hormone, and then plant it in the growing medium almost up to where the leaves are.
5. Place the container in bright, indirect light in a room that’s around 70°F.
6. Keep the soil lightly moist. Roots should form in about a month.
7. Once roots have formed, move the plant to a sunnier spot and space out waterings.

How to Grow Eucalyptus From Seed

When considering how to grow eucalyptus from seed, note that the seeds first must be chilled in the refrigerator for two months before planting. Sow them in the late winter indoors roughly 10 to 12 weeks before your area’s last projected frost date. Use a seed-starting mix in peat pots that you’ll eventually be able to plant right into the soil to avoid disturbing the roots.

1. Sow seeds on top of the growing medium, only lightly covering them.
2. Place the pots in a warm spot with indirect bright light, and keep the growing medium moist but never soggy by misting it.
3. Seeds should germinate in two to three weeks. Once the seedlings are about 6 inches tall, they’re ready to go outdoors.

Potting and Repotting Eucalyptus

Growing eucalyptus in a pot is a great option for gardeners who want to grow the plant outside of its hardiness zone. You can bring it indoors during winter.

Eucalyptus plants don’t like having their roots disturbed, so it’s best to start with a large, 5-gallon container to avoid having to repot. Choose an unglazed clay or plastic pot with plenty of drainage holes. If you must repot, go with a pot 2 inches wider than the previous.

Overwintering

If you’re growing a container eucalyptus plant outside of its hardiness zones, you must bring it indoors to survive the winter. Do not let your plant be exposed to frost, which can damage or kill the foliage. Place it near your brightest window, preferably a southern-facing one, for the winter. Do not fertilize the plant, and slightly back off on watering.

Harvesting Eucalyptus Leaves

It is best to wait until late in the growing season to harvest eucalyptus. If you just want the leaves, simply snip them off with pruners or by hand. Air-dry them on a paper towel or drying screen in a cool spot out of direct sunlight. Wait until the leaves are slightly leathery or crispy, and then store them in glass jars with tightly sealed lids.

Common Pests and Plant Diseases

Eucalyptus plants are fairly free of any major pest or disease issues. But you might occasionally spot eucalyptus long-horned borers, especially on stressed plants. Holes in the bark, oozing sap, and foliage discoloration are signs of an infestation. Remove the infested area of the plant immediately, as insecticides are not effective against borers.

Eucalyptus can be prone to leaf spots, which can appear black on the underside of the leaves and brown on the upper side; cankers; and root rot. The trees are also susceptible to heart rot, which is when the center of the tree begins to rot and decay, extending to the branches as well. Once heart rot occurs, it is impossible to save the tree as the fungus weakens and softens the inside, causing permanent damage. The tree will need to be removed.

Common Problems With Eucalyptus

Eucalyptus trees remain relatively healthy when in their preferred environment. However, in suboptimal conditions, they can come down with certain issues.

Leaves Turning Brown

Leaves turning brown on a eucalyptus tree can be a sign of too little moisture. That’s likely the issue if you notice leaves curling up or dropping as well. In that case, up your watering to keep the soil lightly moist but not soggy. Brown leaves also can be a sign of disease, especially fungal diseases. If just a small area is affected, remove that portion promptly. Or treat with an appropriate fungicide.

Falling Branches

Due to their prospective size and height, eucalyptus trees can become very heavy, causing their branches to fall or break.