Introduction

Asteranthera ovata (Chilean Mitrewort) is a evergreen climber in the Gesneriaceae family, reaching 4 metres with red tubular flowers in summer. Hardy in USDA zones 8-10.

Asteranthera ovata, commonly known as Chilean Mitrewort, is a evergreen evergreen climber in the Gesneriaceae family. The plant reaches 4 metres in height with a spread of approximately 2 metres, climbing by means of aerial rootlets that adhere to surfaces. The red tubular flowers appear in summer, providing seasonal colour. The foliage is green, maintaining its colour year-round as an evergreen. Growth rate is slow-growing, adding less than 30 cm per year. Native to Chile, this species has become a valued ornamental plant in temperate and subtropical gardens worldwide.

Botanical Description

Classification: Gesneriaceae > Asteranthera > ovata. The Gesneriaceae is the botanical family containing the genus Asteranthera. This species is native to Chile and was introduced to European gardens from Chile. The genus Asteranthera contains several species, many of which are valued in horticulture for their climbing habit and ornamental qualities.

Climbing Mechanism

Asteranthera ovata climbs using aerial rootlets that adhere to surfaces. These small, adventitious roots emerge along the stems and secrete a natural adhesive that bonds to rough surfaces such as brick, stone, and bark. This self-clinging mechanism means the plant generally does not require additional support structures on suitable surfaces. The aerial roots can penetrate small cracks and crevices, which may cause cosmetic damage to rendered walls or aging mortar. The plant can reach 4 metres when growing on a suitable vertical surface.

Group Climbing Guide — Evergreen Climber

Mixed — self-clinging (Trachelospermum), twining, or need tying. Year-round weight on supports.

Planting Guide

Step 1 — Site Selection: Choose a position in shade or dappled light with well-drained soil. Consider the mature size (4m tall × 2m wide) when selecting the site. Step 2 — Support Installation: Install a wall (with or without wire supports) or solid vertical surface before planting. Ensure the support is rated for the mature weight of the plant. Step 3 — Soil Preparation: Dig a hole twice the width and 1.5 times the depth of the rootball. Mix in well-rotted compost and a slow-release fertilizer. Target pH 5.5-7.0. Step 4 — Planting: Plant at the same depth as the container (except clematis, which should be planted deeper). Water thoroughly and firm in gently. Step 5 — Aftercare: Mulch with 5-8 cm of organic matter. Water regularly during the first growing season. Guide initial stems toward the support using soft ties. Protect from slugs and snails in the early stages.

Climate & Hardiness

Spring: Apply a balanced slow-release fertilizer as new growth begins. Mulch around the base with organic matter. Tie in new stems to supports. Check for winter damage and prune out any dead or damaged growth. Summer: Water regularly , especially during dry spells. Feed monthly with a liquid fertilizer during the growing season. Continue training and tying in new growth. Deadhead if applicable. Autumn: Reduce watering and feeding as growth slows. Apply a thick mulch to protect roots from winter cold. Check for any pest or disease issues before winter. Winter: Protect from severe frost with horticultural fleece if temperatures drop below -10°C. Check ties and supports. Plan any structural pruning for late winter.

Overwintering Guide

Protect from cold drying winds. Fleece in severe frost. Water in dry winter spells — evergreens transpire year-round.

Propagation

Stem cuttings (primary method): Take semi-ripe cuttings in mid to late summer (July-August). Select healthy, current season's growth, cutting just below a leaf node. Cuttings should be 10-15 cm long. Remove lower leaves, dip the cut end in hormone rooting powder, and insert into a well-drained mix of perlite and peat (50:50). Place in a propagator or cover with a clear plastic bag. Bottom heat of 18-21°C improves success rates. Roots typically develop within 4-8 weeks. Success rate: 60-80%. Layering (alternative): In spring, select a low-growing flexible stem. Wound the underside lightly, pin it to the ground with a wire staple, and cover with soil. Keep moist. Roots develop over 6-12 months. Sever from the parent plant and transplant the following season. Success rate: 80-90%.

Pests & Diseases

Common Problems

Group Disease & Pest Reference (Evergreen Climber)

• Scale insects — brown bumps on stems and leaves; winter oil wash, hand removal
• Sooty mould — black coating from honeydew (scale/aphids); treat the pest, mould cleans off naturally
• Leaf spot — in wet weather; mostly cosmetic; improve circulation
• Cold damage — browning of foliage in severe frost; protect with fleece, prune out damaged growth in spring
• Phytophthora — in waterlogged conditions; ensure excellent drainage; avoid heavy clay without amendment

Training & Pruning

Pruning timing: Prune after flowering or in early spring. Formative pruning: In the first 2-3 years, focus on building a strong framework of main stems by selecting well-placed shoots and tying them to the support. Remove weak, crossing, or badly-placed stems. Maintenance pruning: Once established, shorten side shoots after flowering to maintain shape and encourage new flowering wood. Remove any dead or damaged growth promptly. Thin overcrowded stems to maintain good air circulation. Training: Tie in new growth regularly throughout the growing season using soft garden twine or plant clips. Spread stems evenly across the support for the best coverage and flowering display. Self-clinging species need minimal tying once established.

Pruning Guide — Evergreen Climber

Light trim in spring after last frost. Remove damaged growth. Avoid hard pruning — slow to regrow.

Support Structures

Asteranthera ovata is a self-clinging climber that generally does not require additional support structures on suitable surfaces. However, young plants may need initial guidance: Suitable surfaces: Brick, stone, rough-rendered walls, mature tree trunks. The plant adheres best to rough, porous surfaces. Temporary support: Use small nails or adhesive hooks to guide young growth until the plant's own attachment mechanism takes hold (usually within one growing season). Weight considerations: Mature plants can be extremely heavy. Ensure the wall or structure is sound before allowing extensive growth. A mature specimen covering a large wall area can weigh hundreds of kilograms when wet. Dimensions: Allow for a mature height of 4m and spread of 2m.

Support Guide — Evergreen Climber

Sturdy trellis, wire systems, wall-fixed battens. Must support year-round leaf weight inc. snow load.

Wildlife Value

Asteranthera ovata is highly attractive to hummingbirds, which are drawn to the tubular flowers rich in nectar. The plant also benefits bees, butterflies, and other pollinating insects. The dense foliage provides nesting cover for small birds. Ecosystem services: Provides nectar, pollen, shelter, and nesting sites. The climbing habit creates vertical habitat layers, increasing garden biodiversity.

Landscape Design

Walls and fences: Asteranthera ovata is well-suited to covering walls and fences, providing year-round screening. Self-clinging habit means no additional wiring is needed on rough surfaces. Pergolas and arbors: Excellent choice for pergolas, creating a dramatic overhead canopy. Screening: Creates year-round screening when grown on appropriate support. Effective for disguising unsightly structures, dividing garden rooms, or creating private spaces. Ground cover: Can also be allowed to scramble as ground cover on banks or over low walls. Combine with other climbers for a layered, naturalistic effect.

History & Culture

Asteranthera ovata has been cultivated in gardens since its introduction from Chile. Originally from Chile, it has become valued in horticulture for its ornamental qualities. The genus Asteranthera has contributed significantly to the diversity of climbing plants available to gardeners, with species found across multiple continents and climate zones.

Container Growing

Asteranthera ovata is not recommended for container growing due to its vigorous root system and large mature size (4m). The plant requires open ground to develop a sufficiently large root system for healthy growth and flowering. If space is limited, consider a more compact cultivar or alternative species better suited to container culture.

Frequently Asked Questions

Seasonal Care Calendar