Lemon eucalyptus (Corymbia citriodora)

Overview

Corymbia citriodora, widely recognized as Lemon eucalyptus, offers a striking aromatic presence in the garden, prized for its distinct lemon-scented leaves. Native to Australia, this plant is valued for its fast growth, especially when young, making it a popular selection for quick visual impact or annual display in cooler climates. Even when grown small, the foliage provides a unique olfactory element unmatched by many other common landscape trees.

While this species can mature into a very tall evergreen specimen in its native habitat, gardeners outside of tropical regions often treat Corymbia citriodora as a vigorous annual or a container plant. Its smooth gray bark and narrow, lance-shaped, yellowish-green leaves contribute significantly to its ornamental appeal. Growing Lemon eucalyptus successfully relies heavily on providing the right conditions for its moisture and sun needs.

Gardeners should recognize the benefits of choosing Corymbia citriodora for its generally low susceptibility to common pests and diseases. Its compact size when treated as an annual allows for flexibility in patio designs or seasonal bedding schemes, bringing the unique character of the lemon-scented gum to any sunny spot.

Fast Facts

• Plant Family: Myrtaceae
• Plant Type: Tree
• Native Range: Australia
• Hardiness Zones: USDA Zones 8-11
• Size at Maturity:
  • Height: 6-10 ft
  • Spread: 2-4 ft
• Bloom Time: Rarely flowers
• Bloom Description: White
• Sun Exposure: Full sun
• Water Needs: Medium
• Maintenance Level: Medium

How to Grow

For successful establishment, plant Corymbia citriodora when the danger of frost has passed, providing it with full sun exposure throughout the growing season. It thrives in medium moisture conditions but requires soil that is notably well-drained to prevent root issues. Good drainage is perhaps the most critical cultural requirement for this species.

Watering should be consistent during periods of active growth, meeting its medium water needs. Fertilizing is generally not necessary if grown as an annual; focus instead on ensuring consistent moisture without saturation. Pruning is usually only required for shaping container specimens or managing growth when grown indoors during winter.

A key consideration for colder regions (Zones 8-11) is overwintering. If you are growing Lemon eucalyptus in a container, it must be brought indoors before the first fall frost hits, as it is not reliably cold-hardy when temperatures dip too low. In the St. Louis region context, it is frequently started from seed for rapid summer growth. Tolerating drought once established is a significant benefit, though regular watering is recommended for optimal rapid performance as an annual.

Landscape Uses

The versatility of Corymbia citriodora makes it excellent for several landscape applications, particularly where its fragrance can be enjoyed up close. It is highly functional when used as a garden annual, allowing gardeners in cooler zones to enjoy its tropical look and scent for a single season before refreshing next year. Alternatively, it excels as a container plant on patios or decks.

When treating the Lemon eucalyptus as a container specimen, it can be easily maneuvered. You can sink pots directly into the ground up to the lip for a seamless look, then retrieve them before winter. This flexibility means this striking Australian native need not be confined only to its hardiness range.

Use it as a fragrant focal point in mixed annual displays or as a narrow vertical accent where space is limited. Its upright, slender habit contrasts nicely with lower, mounding bedding plants, and its clear foliage brightens up beds that receive full sun exposure all day long.

Standout Features

Flower Qualities

• Showy

Noteworthy Characteristics

Corymbia citriodora, commonly called lemon-scented gum is native to Australia. It is a tall, slender, broadleaf evergreen tree that will grow 60-100’ tall in its native habitat. Features smooth gray bark and narrow lance-shaped yellowish-green leaves (to 7” long) that are lemon-scented. Small white flowers in 3-flowered umbels. Flowers rarely appear on young trees or container plants. In the St. Louis area, it may be grown as an annual from seed, typically growing rapidly to 6-8’ tall in one growing season. Synonymous with Eucalyptus citriodora.

Tolerances

• Drought

Potential Problems

Corymbia citriodora generally exhibits few serious pest or disease issues, which simplifies its management across its growth stages. Gardeners should maintain vigilance regarding proper soil drainage, as overly wet conditions pose a greater risk than actual pest pressure for this species. By ensuring full sun exposure and appropriate watering, you can best mitigate any potential environmental stress.

Frequently Asked Questions

What hardiness zones is Lemon eucalyptus suitable for?

Corymbia citriodora is winter hardy to USDA Zones 8 through 11.

How large does Lemon eucalyptus grow?

As a container plant or annual in non-native areas, expect heights between 6 to 10 feet, though its mature size in its native Australia is much larger.

What sun exposure does Corymbia citriodora need?

This plant performs best when situated in a location that receives full sun exposure daily.

When does Corymbia citriodora bloom?

Flowers on Corymbia citriodora rarely appear, especially on younger or containerized specimens, but when they do occur, they are white.

Conclusion

The Corymbia citriodora, or Lemon eucalyptus, offers exceptional aromatic value and a handsome, slender silhouette, making it a rewarding choice whether grown as a fast-developing annual or a container specimen for patio display. Confirming your local hardiness zone compatibility is crucial; if you are in Zones 8-11, you have greater potential for long-term growth, otherwise, plan to bring your Lemon eucalyptus indoors before the first frost.

Design Ideas

Because the Lemon eucalyptus grows rapidly, it functions perfectly as temporary vertical accent planting. Use it near entrances or seating areas where its lemon fragrance is easily released when foliage brushes against people or objects. Its relatively small potential spread (2-4 ft) means it won’t quickly overtake neighboring annuals or perennials.

When planting Corymbia citriodora in containers, group it with broad-leafed, lower-growing plants that share the requirements for full sun and medium moisture. Think about companions with deep green or variegated foliage to contrast against the yellowish-green leaves of the eucalyptus, enhancing its visual pop throughout the summer season.

Companion Planting

When growing Corymbia citriodora in the ground within its established zones, consider pairing it with other drought-tolerant, full-sun perennials that appreciate excellent drainage. Plants that thrive in similar tough conditions will help ensure the entire planting scheme remains cohesive and easy to maintain. Remember that in its container form, companion choices are limited only by container size and the need to avoid root competition near the base of the tree.