Coprosma repens ‘Marble Queen’ (Mirror Plant)

Coprosma repens ‘Marble Queen’ is an eye-catching evergreen shrub known for its striking variegated foliage. It features glossy leaves that combine patches of green with creamy white, often with hints of pink in cooler temperatures. This color contrast creates a luminous effect in garden settings, making it a favorite among landscape designers and garden enthusiasts.

Coprosma repens ‘Marble Queen’ – Mirror Plant: An In-depth Look

Native: Coprosma repens is native to New Zealand, where it is found in coastal areas and forest margins. It belongs to the coffee, madder, or bedstraw family (Rubiaceae), which includes popular genera such as Coffea (coffee), Gardenia, Cinchona (quinine), Ixora, and Rubia (madder).

Plant Type and Habit: Coprosma ‘Marble Queen’ is a dense, evergreen shrub that maintains its foliage throughout the year. Its growth habit is compact and rounded, making it ideal for use as a decorative element in both gardens and container plantings.

Size: This cultivar typically grows to a height of about 3-5 feet (90-150 cm) and spreads about 4-6 feet (120-180 cm). Its moderate growth rate allows it to fill in spaces without becoming unruly, making it manageable for most garden sizes.

Flowers: The flowers are small, inconspicuous, and yellowish. The blooming period occurs in the late spring. However, the flowers are not prominently displayed, and many gardeners grow the plant primarily for its decorative leaves. Following the flowering stage, small, orange berries may develop, usually in hidden positions beneath the leaves. These fruits are typically not prominent and are overshadowed by the foliage in terms of visual interest.

Foliage: The variegated leaves are the most notable feature of Coprosma ‘Marble Queen.’ The leaves are oval, glossy, and have a thick, leathery texture. They are heavily splashed with creamy-white and keep their variegation throughout the year, with color intensity sometimes increasing during colder months.

Hardiness: It is relatively hardy, suitable for USDA zones 9 to 11. It can tolerate mild frost but needs protection from harsh winter conditions.

Award: Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society.

Uses: Due to its compact size and striking foliage, Coprosma ‘Marble Queen’ is extensively used for ornamental purposes in landscapes. It serves well as a border plant, in rockeries, or as part of foundation plantings. It is also popular in containers where its foliage can be showcased on patios or balconies.

Wildlife: The berries attract birds, particularly in winter when food is scarce, making it a valuable plant for supporting local wildlife.

Toxicity: Coprosma repens plant is considered non-toxic, although it’s still advisable to discourage pets and children from ingesting any plant material as a precaution.

Deer and Rabbits: Generally, Coprosma repens is deer resistant.

Drought / Salt Tolerance: It exhibits good drought resistance once established. It is also highly tolerant of salt spray and coastal winds, making it an ideal choice for seaside gardens and exposed, windy locations.

Invasiveness: Coprosma repens is currently reported as invasive in South Africa. It’s important to monitor and manage its growth to prevent it from overtaking native plant species.

Benefits: The aesthetic appeal of ‘Marble Queen’ is its primary benefit, enhancing garden designs with its colorful foliage. It also serves as a low-maintenance option for year-round greenery in appropriate climates. Additionally, its dense growth can provide shelter for small wildlife and contribute to the ecological diversity of garden spaces.

How to Grow and Care for Coprosma repens

Coprosma repens is highly tolerant of salt spray and coastal winds, making it an ideal choice for seaside gardens and exposed, windy locations.

Light: Coprosma repens thrives in full sun to partial shade. More sunlight encourages brighter leaf colors.

Soil: Plant in moist, well-drained soil with a neutral or slightly acidic pH.

Exposure: Choose a site that is somewhat protected from extreme cold winds but can handle coastal breezes.

Planting: Plant in spring or autumn to give the plant time to establish before extreme weather conditions. Dig a hole twice as wide as the root ball and just as deep. Mix in some compost or aged manure to enrich the soil if needed. Place the plant in the hole so that the top of the root ball is level with the soil surface, then fill in and firm the soil around the base.

Water: Water regularly to keep the soil moist but not soggy until the plant is established. The roots are likely to rot if the soil remains muddy. Once established, Coprosma repens is somewhat drought tolerant but benefits from occasional watering during prolonged dry spells, especially in hotter climates.

Fertilizer: Feed with a balanced, slow-release fertilizer in early spring to support new growth. Follow the manufacturer’s instructions for the correct dosage and method of application.

Pruning: Prune in late winter or early spring before new growth starts. Regular pruning helps maintain the desired shape and size, encourages bushier growth, and can rejuvenate older plants.

Mulching: Apply a layer of organic mulch around the base to conserve moisture, suppress weeds, and maintain a cool root environment. Use bark, shredded leaves, or other organic materials.

Winter Protection: In cooler regions (outside USDA zones 9 to 11), provide some winter protection such as mulching around the base or using frost cloths over the plants during particularly cold snaps.

Coprosma repens Propagation – A Step-By-Step Guide

Propagating Coprosma repens is a relatively straightforward process that can be done through cuttings, allowing gardeners to create new plants that are true to the parent’s characteristics.

Timing: The best time to take cuttings is in late spring through summer when the plant is actively growing.

Selecting Cuttings: Choose healthy, non-flowering shoots from the current season’s growth. These should be firm and slightly woody at the base.

Preparing Cuttings: Cut a 4-6 inch section of stem just below a leaf node using a sharp, clean knife or secateurs. Strip the lower leaves off the cutting, leaving two to four leaves at the top. If the remaining leaves are large, consider cutting them in half horizontally to reduce moisture loss. Though not always necessary, applying a rooting hormone to the cut end can enhance rooting success. Dip the base of the cutting into the rooting hormone powder or solution.

Planting: Fill a pot with a mix of perlite and peat moss or a well-draining potting mix formulated for cuttings. Insert the cutting into the potting mix, ensuring that at least two nodes (where the leaves were removed) are below the surface. Firm the mix around the cutting to secure it in place.

Environment: Place the pot in a warm, bright location out of direct sunlight. A greenhouse or plastic cover can be used to maintain humidity around the cutting, which helps prevent it from drying out before it roots. Ensure the potting mix remains moist but not soggy.

Rooting: Root development typically occurs within 4 to 8 weeks, depending on the conditions. To test if roots have formed, gently tug on the cutting; resistance indicates root growth. Once the cuttings have rooted and show new growth, begin to acclimatize them to less humid conditions by gradually removing any plastic covering. When the plants are sturdy enough, transplant them into individual pots with standard potting soil.

Transplanting: Before planting them outdoors, acclimate the new plants to outdoor conditions by gradually increasing their exposure to the elements over a week or two. This process is known as hardening off. After hardening off and once they’ve grown sufficiently in their pots, the new Coprosma plants can be transplanted to their final position in the garden during a mild time of year, either spring or autumn.

Coprosma repens: Pests, Diseases, Common Problems

Coprosma repens is generally robust and resistant to many pests and diseases, but like any garden plant, it can occasionally encounter problems.

Pests

Mealybugs: These are a type of sap-sucker that secretes a white, waxy substance which can lead to the growth of sooty mold. Treat infestations with insecticidal soap, neem oil, or by removing them manually using a cotton swab dipped in alcohol.

Scale insects: These small, sap-sucking pests attach themselves to the stems and leaves, potentially causing yellowing or stunted growth. Scale can be controlled by wiping them off manually with a cloth dipped in soapy water or using an appropriate insecticide or neem oil.

Diseases

Root rot: This is usually a result of overwatering or poor drainage. Ensure that the soil is well-draining and that you’re not watering the plant too much, especially during cooler months.

Leaf spot: Spots on the leaves can be a sign of fungal infection, often exacerbated by wet conditions. Improve air circulation around the plants, avoid overhead watering, and remove affected foliage. Fungicidal sprays may be necessary for severe cases.

Common Problems

Leaf Drop: Coprosma repens may drop leaves in response to sudden changes in temperature, particularly in colder climates or when moved indoors for winter. Gradually acclimate the plant to new conditions to minimize stress.

Discoloration of Leaves: Leaves might turn yellow due to poor nutrition, particularly a lack of nitrogen or iron. This can be corrected with appropriate fertilizers. Variegated varieties may revert to green in too much shade; if this is undesirable, increase light levels.

Frost Damage: While Coprosma repens is somewhat frost-tolerant, sudden severe frosts can damage foliage. Protect plants with frost cloth or move container plants to a sheltered location during cold snaps.