What is the difference between pseudopanax crassifolius juvenile and adult forms?

Pseudopanax crassifolius (lancewood) undergoes one of the most dramatic juvenile-to-adult foliage transitions of any commonly cultivated plant: the juvenile form (which persists for many years and is the stage most frequently seen in UK gardens) has extraordinarily long, narrow, dark bronze-black, strap-like leaves with coarsely toothed margins, hanging downward from the upright stem and sometimes reaching 1 m or more in length; the overall effect of a young lancewood is unlike any other commonly grown plant in the UK garden and is immediately recognisable as a New Zealand native even to observers unfamiliar with the species. The adult form, which develops only after many years (typically more than ten years in UK conditions, often longer) and only on plants that have reached a significant size, has much shorter, broader, more conventional-looking leaves in a palmate arrangement; the adult plant is an attractive but architecturally much less dramatic small tree or large shrub. In UK gardens, where outdoor-grown specimens rarely reach the size and age at which the adult foliage fully develops, the juvenile form is typically permanent and is the form for which the plant is selected and grown. The transition from juvenile to adult is an intermediate process rather than a sudden change; intermediate forms with leaves of intermediate proportions and arrangement appear as the plant matures. Container-grown plants in UK conditions rarely, if ever, reach the adult foliage stage; outdoor-grown specimens in very mild UK gardens may eventually begin the transition after many decades.

Plant problems

Why Are My Pseudopanax Leaves Curling?

Q: Why are my pseudopanax leaves curling?

Pseudopanax (lancewood or five-finger) leaves curl and drop most commonly in UK gardens because of cold damage in hard winters (pseudopanax is marginally hardy in most of the UK and the leathery, strap-like or palmate leaves curl and drop in hard frost), drought stress (the large, leathery leaves curl inward when the root zone dries out in summer), or waterlogging in heavy, poorly draining soils. Pseudopanax is a genus of around 20 species of evergreen shrubs and small trees from New Zealand, Chile, and the Pacific islands; the species most commonly grown in UK gardens are New Zealand natives with highly distinctive juvenile and adult foliage forms. Pseudopanax crassifolius (lancewood) is the most widely grown species in UK gardens: the juvenile form, which is the stage most commonly seen in UK garden centres, is remarkable for its long, strap-like, toothed, bronze-black, downward-hanging leaves (often 1 m or more in length on young plants) that give the young tree a completely different appearance from any other common UK garden plant and a dramatic, almost prehistoric visual effect. As the plant matures over many years, the adult foliage is entirely different: shorter, broader, softer, more conventional in appearance. Pseudopanax lessonii (houpara) is another commonly grown species with palmate, three to five leaflet leaves that are broader and more conventional in shape; it is marginally less hardy than P. crassifolius. Both species are grown as architectural, foliage plants for dramatic visual impact in UK gardens and containers. Pseudopanax ferox (toothed lancewood) is similar to P. crassifolius but with even more dramatically toothed, spine-margined juvenile leaves.

Q: Is pseudopanax hardy in the UK?

Pseudopanax crassifolius is the hardiest commonly grown species, surviving to approximately -8 to -10°C in a sheltered position with freely draining soil, and is reliably perennial in the mildest UK gardens (sheltered coastal and urban gardens in south-west England, Wales, London, and similar mild positions). In most of the UK, particularly north of the Midlands and in exposed positions, P. crassifolius is not reliably hardy outdoors and is best grown in containers that can be brought under glass from October to May. Pseudopanax lessonii is slightly less hardy (to about -6 to -8°C) and requires even more shelter and frost protection. The dramatic juvenile foliage of P. crassifolius, with its long, dark, strap-like hanging leaves, makes it a visually striking container plant and it is increasingly popular as a large architectural container specimen on patios and terraces, where it can be overwintered in a frost-free conservatory or cool greenhouse in most UK areas. Container growing is arguably the best approach to pseudopanax in UK conditions outside the very mildest gardens: it allows the plant's extraordinary form to be displayed prominently in summer and protected from frost in winter. In the mildest UK outdoor gardens, pseudopanax can develop into a medium-sized tree over many years and the transition from juvenile to adult foliage is an interesting long-term garden feature.

Q: How do I grow pseudopanax in the UK?

Pseudopanax grows best in a sheltered, sunny to lightly shaded position in freely draining, moderately fertile, neutral to slightly acid soil. The plants are tolerant of coastal conditions (salt wind, freely draining, sandy soils) and are well suited to sheltered seaside gardens. In most UK areas, container growing is the most practical approach: use a large container of loam-based compost (John Innes No. 3) with added grit for drainage; move under glass from October to May in cold areas; repot every two to three years in spring. Feed container-grown plants with a slow-release balanced fertiliser in spring and a liquid feed monthly from May to August. The extraordinary juvenile foliage of P. crassifolius, with its hanging, toothed, strap-like dark leaves, is the primary ornamental feature: a well-grown juvenile plant in a large container can be 1 to 2 m tall with leaves up to 1 m long, providing a truly dramatic vertical accent on a patio or terrace. In the ground in mild UK gardens, plant in a warm, sheltered position in freely draining soil; mulch the root zone in autumn; avoid waterlogged or heavy clay soils. The plant is slow-growing; allow five to ten years or more for a container specimen to develop its full dramatic juvenile foliage effect.

Pseudopanax crassifolius (lancewood) is a New Zealand evergreen small tree with one of the most dramatic juvenile foliage effects of any plant grown in the UK: long, hanging, toothed, bronze-black strap-like leaves up to 1 m long give young plants a strikingly prehistoric appearance. Marginally hardy in most of the UK, it is best grown in containers that can be overwintered under glass. Cold damage and drought stress are the most common causes of leaf curl.

Cold damage

Cold damage curls, browns, and drops the leathery leaves of pseudopanax in hard UK winters; Pseudopanax crassifolius is damaged by frost below about -8 to -10°C and Pseudopanax lessonii below about -6 to -8°C. The long, strap-like juvenile leaves of P. crassifolius curl inward and may go limp before browning; the stem usually survives moderate frost even when the leaves are killed, and the plant typically regrows from surviving buds in spring. In a very hard frost, the stem may also be killed; regrowth from the base is possible but not guaranteed.

What to do

Move container-grown plants under glass from October to May in most of the UK; a frost-free conservatory or cool greenhouse is ideal. For outdoor specimens, choose the warmest, most sheltered south or west-facing wall position; mulch the root zone in autumn; wrap young plants in fleece from November to March. Do not remove apparently dead or damaged growth until April or May when the extent of regrowth confirms what has survived.

Drought stress

The large, leathery leaves of pseudopanax curl inward along their length when the root zone dries out in summer; container-grown plants are particularly vulnerable because the restricted root volume dries out rapidly in warm weather. The long, strap-like juvenile leaves of P. crassifolius have a large surface area relative to the stem diameter and can transpire significant volumes of water on hot days. Established in-ground plants in well-prepared, mulched soil rarely suffer significant drought stress in average UK summer conditions.

What to do

Water container-grown plants regularly in summer; check every 1 to 2 days in warm weather. Use a large container to provide a greater root volume and reduce drying rate. Mulch in-ground plants with bark. The leaves recover quickly when watered; the curl is a reversible stress response and is not usually damaging if corrected promptly.

Waterlogging

Pseudopanax does not tolerate waterlogged or persistently wet soil; the roots rot in saturated conditions, causing progressive leaf yellowing, curl, and plant decline. The problem is most acute in heavy clay soils and in containers without drainage holes. Freely draining soil is essential for container-grown plants overwintered in a cool greenhouse or conservatory where irrigation control may be imprecise.

What to do

Plant in freely draining, moderately fertile soil; add grit to clay soils. Ensure containers drain freely and are elevated on pot feet. Reduce watering to a minimum in autumn and winter; pseudopanax needs far less moisture when dormant. Use loam-based compost (John Innes No. 3) with 20 to 30% added coarse grit for container growing.

Frequently asked questions

Why are my pseudopanax leaves curling?

Pseudopanax leaves curl most commonly because of cold damage (the leathery leaves brown and curl below -8°C; move containers under glass from October; regrowth from the stem or base is common after moderate frost damage), drought stress in containers (water regularly in summer; the large leaves transpire quickly; recover when watered), or waterlogging (roots rot in saturated soil; use gritty, freely draining compost). Container growing with winter glass protection is the most reliable approach in most UK areas.

Is pseudopanax hardy in the UK?

Pseudopanax crassifolius is hardy to about -8 to -10°C in a sheltered position and is reliably perennial only in the mildest UK gardens (south-west England, sheltered coastal and urban positions). In most of the UK, container growing with winter glass protection from October to May is the most reliable approach. P. lessonii is slightly less hardy. Both species are excellent as large, architectural container specimens on summer patios.

How do I grow pseudopanax in the UK?

In containers: use large pots of John Innes No. 3 compost with added grit; feed monthly from May to August; water regularly in summer; move under glass from October to May. In the ground (mild gardens only): sheltered, sunny, freely draining position; mulch in autumn; avoid clay or waterlogged soils. The extraordinary juvenile foliage of P. crassifolius (hanging, strap-like, bronze-black leaves up to 1 m long) is the main ornamental feature and is best displayed against a simple, light background.

What is the difference between pseudopanax juvenile and adult forms?

Pseudopanax crassifolius has one of the most dramatic juvenile-to-adult foliage transitions of any cultivated plant: juvenile plants have long (up to 1 m), narrow, dark bronze-black, hanging, toothed strap-like leaves unlike any other common UK garden plant; adult foliage (developing only after many years) is shorter, broader, palmate, and far more conventional in appearance. In UK garden conditions, most plants remain in the juvenile form indefinitely and are selected primarily for this dramatic effect.