Plant problems

Why Are My Lapageria Leaves Curling?

Q: Why are my lapageria leaves curling?

Lapageria (Chilean bellflower or copihue) leaves curl and yellow most commonly in UK cultivation because of drought stress during the growing season (lapageria requires consistently moist but freely draining, acid soil; the narrow, leathery, lance-shaped, dark green leaves curl along their length and become dull and limp when the roots dry out; lapageria is an evergreen twining climber that grows actively through the cooler, moister UK seasons and is poorly adapted to summer drought), lime or alkaline soil causing iron deficiency chlorosis (lapageria is calcifuge and intolerant of alkaline or limey conditions; on soils with a pH above approximately 6.5, the leaves become pale, yellowish, and eventually curl and brown at the margins as iron and manganese become chemically locked up and unavailable to the roots; the problem is progressive and worsens each season on unsuitable soil), or hard frost in winter (lapageria is borderline hardy in the UK; the fleshy, rhizome-based root system typically survives to about -5 to -8°C in a sheltered, well-drained position, but the above-ground stems and leaves are damaged by hard frost below about -5°C, curling and collapsing before going brown). Lapageria rosea is the only species in its genus (Lapageriaceae, or placed in Philesiaceae by some authorities) and is the national flower of Chile; it is an evergreen twining climber to 3 to 5 m from the cool temperate rainforest understorey of southern Chile, producing large (6 to 8 cm), waxy, pendant, tubular flowers in deep rose-pink, pale pink, or white (cultivar dependent) from June to November in the UK, with peak flowering typically in August and September.

Q: Is lapageria hardy in the UK?

Lapageria is borderline hardy in the UK and can be grown outdoors in sheltered, mild gardens, primarily in the west and south-west of England, Wales, Scotland, and Ireland where Atlantic maritime conditions prevent the most severe winter frosts. In these mild areas (coastal Cornwall, west Wales, western Scotland, coastal west Ireland, sheltered London gardens) lapageria has grown for many decades in sheltered, shaded or semi-shaded wall positions, often on north or west-facing walls where summer temperatures are not excessive and the roots remain cool and moist. The hardiness threshold is approximately -5 to -8°C for the roots (which regrow even if the tops are damaged) and -3 to -5°C for the above-ground stems. In most of inland and eastern England, lapageria is grown in a cool greenhouse or conservatory, or in a container that can be moved under cover from November to late March. The critical requirements for outdoor success are: a sheltered position (especially from cold, drying winter winds), freedraining but moisture-retentive acid soil, a north or west-facing aspect (not south-facing, where summer heat dries the roots and exceeds the plant's preferred temperature range), and a position where hard frosts are rare. Mulching with acid leaf mould or composted bark from November to March significantly improves cold survival.

Q: How do I grow lapageria in the UK?

Lapageria grows best in a sheltered, shaded or semi-shaded position (a north, north-west, or west-facing wall is often better than a south-facing wall in UK conditions) in deep, moisture-retentive, humus-rich, freely draining, acid soil with a pH of approximately 5.5 to 6.5. The plant comes from the cool, shaded, moist understorey of Chilean temperate rainforest and does not thrive in the hot, dry, alkaline or limey conditions that many garden climbers prefer. Prepare the soil thoroughly before planting by incorporating generous quantities of leaf mould, composted bark, or ericaceous compost; test the pH and correct if necessary. Provide support: lapageria twines its stems around wires, trellis, or a host plant to climb; space horizontal wires at 30 to 40 cm intervals and install them before planting to avoid root disturbance. Water consistently throughout the growing season; lapageria does not tolerate drying out. Mulch the root zone every spring with a 5 to 10 cm layer of acid leaf mould or composted bark; this maintains soil moisture, maintains acidity, and feeds the soil microbiota. Never use lime, mushroom compost, or alkaline materials near lapageria. Grow in containers in ericaceous compost (John Innes ericaceous or a peat-free ericaceous mix plus 20% perlite) if your garden soil is neutral or alkaline; use rainwater or filtered water for irrigation. Feed monthly from April to September with a balanced ericaceous liquid fertiliser.

Lapageria rosea (Chilean bellflower or copihue) is Chile's national flower: an evergreen twining climber from the cool, shaded rainforest understorey with leathery, dark green leaves and extraordinary pendant, waxy, tubular flowers in deep rose-pink from June to November. In the UK it needs a sheltered, semi-shaded position in deep, moist, acid soil. Drought and lime intolerance are the primary causes of leaf curl.

Drought stress

Drought is the most common cause of lapageria leaf curl in UK cultivation; the narrow, leathery leaves curl along their length and lose their lustrous dark green colour when the root zone dries out. Lapageria comes from the permanently moist, shaded rainforest understorey of southern Chile and has no adaptation to summer drought. Wall-trained plants in a sheltered UK position and container-grown specimens are most vulnerable, particularly in a hot, dry UK summer.

What to do

Water consistently throughout the growing season; do not allow the root zone to dry out at any point from spring to autumn. Mulch the root zone every spring with a 5 to 10 cm deep layer of acid leaf mould or composted bark to retain moisture and keep the roots cool. Container plants need daily checking in hot weather; use rainwater or filtered water to avoid raising soil pH. A drip irrigation system at the root zone is ideal for wall-trained plants in hot, dry summers.

Lime or alkaline soil

Lapageria is strictly calcifuge; any soil with a pH above approximately 6.5 causes progressive iron and manganese deficiency, producing yellowing between the leaf veins (interveinal chlorosis), followed by leaf margin browning, curling, and eventual dieback. Alkaline tap water used for irrigation can raise soil pH over time even in initially acid soil. Mushroom compost, chalk, limestone grit, or lime incorporated near the roots causes immediate and irreversible damage.

What to do

Test soil pH before planting; target 5.5 to 6.5. In neutral or alkaline gardens, grow in a container in ericaceous compost (peat-free ericaceous mix plus 20% perlite) and irrigate with collected rainwater. Apply iron chelate (sequestered iron) monthly from April to August if yellowing is already present. Never apply lime, mushroom compost, or alkaline materials within 2 m of lapageria roots. Mulch each spring with acid leaf mould only.

Cold damage

Hard frost below about -5°C damages lapageria stems and leaves; the above-ground growth turns brown and collapses after a prolonged freeze, though the root system typically survives and produces new growth from the base in spring if the soil has not frozen solid. Cold, drying winter winds are as damaging as frost; the leaves curl, desiccate, and turn brown when the plant loses moisture through the leaf surface faster than the roots can supply it from cold, frozen soil.

What to do

In cold or exposed UK gardens, wrap stems in double fleece from November to late March and pack the root zone with a generous dry bark mulch (10 to 15 cm). A sheltered, north-west facing wall position provides frost protection without the summer heat that stresses lapageria from the south. In cold inland UK gardens, grow in a cool greenhouse or large conservatory. Even if all above-ground stems are killed, new growth from the rootstock often emerges in May if the roots are protected.

Frequently asked questions

Why are my lapageria leaves curling?

Lapageria leaves curl most commonly because of drought stress (curl along the length; water consistently; mulch the root zone; never allow drying out), lime or alkaline soil causing iron deficiency (yellowing with veins still green; grow in ericaceous compost; use rainwater; apply sequestered iron), or cold damage in hard winters (stems brown and collapse below -5°C; mulch roots generously; wrap stems in fleece from November). Consistently moist, acid, humus-rich soil and a sheltered semi-shaded position are the keys to healthy lapageria in the UK.

Is lapageria hardy in the UK?

Lapageria is borderline hardy and grows outdoors reliably in sheltered, mild UK gardens (coastal Cornwall, west Wales, western Scotland, coastal west Ireland, sheltered London). The roots tolerate approximately -5 to -8°C in free-draining conditions; the stems are damaged below about -5°C. In cold or wet inland UK gardens, grow in a cool greenhouse or large conservatory, or in a container moved under cover from November to March. A north or west-facing sheltered wall is often better than a south-facing position.

How do I grow lapageria in the UK?

Grow in a sheltered north, north-west, or west-facing position in deep, moist, humus-rich, acid soil (pH 5.5 to 6.5). Prepare the soil with generous quantities of leaf mould or ericaceous compost. Install horizontal support wires at 30 to 40 cm intervals before planting. Water consistently throughout the growing season; never allow drought. Mulch every spring with acid leaf mould. Feed monthly April to September with ericaceous liquid fertiliser. In alkaline gardens, grow in a container in ericaceous compost irrigated with rainwater.

When does lapageria flower in the UK?

Lapageria flowers in the UK from approximately June to November, with peak flowering from August to October. The extraordinary pendant, waxy, tubular flowers (6 to 8 cm) in deep rose-pink (or pale pink/white in cultivars) last two to three weeks each on the plant. Well-established plants in favourable positions produce dozens of flowers over the season. The late season makes lapageria particularly valuable as almost nothing else of this quality flowers in a UK garden through October and November.