<em>Pseudopanax</em>: planting, cultivation and care

Description and botany

Pseudopanax are evergreen trees or bushes, with very architectural, striking foliage. Most originate from New Zealand, where they grow mainly in forests and scrub. Species are also found in Australia (Tasmania) and in Chile. These are ancient, relatively primitive plants.

There are seven Pseudopanax species. The most cultivated is Pseudopanax ferox, a truly original and surprising tree, with a very straight trunk and linear leaves directed downwards. Pseudopanax lessonii is also grown and has produced many horticultural varieties, each showing variations in leaf shape and colour: ‘Goldsplash’, ‘Dark Star’, ‘Goldfinger’, etc. Pseudopanax crassifolius is also in cultivation.

Pseudopanax belongs to family Araliaceae (which counts more than 1,500 species), like ivy, Fatsia japonica, Tetrapanax or Cussonia. Also in this family is Aralia elata, sometimes called angelica tree, which offers finely divided leaves and large white inflorescences.

Pseudopanax can reach up to 6–7 m in height, and up to 15 m for Pseudopanax crassifolius. They are fairly fast-growing trees. In juvenile form, which can last many years, Pseudopanax ferox and Pseudopanax crassifolius have a very upright habit, with a single, not ramified trunk. They bring a lot of verticality to a border. When they become adult (after about 15 years), these Pseudopanax begin to ramify, producing at the top of the trunk branches in different directions and forming a small rounded crown. Their crown widens and becomes ramified. Likewise, over time leaves disappear at the base, leaving the trunk naked. Trunk of Pseudopanax ferox can reach up to 25 cm in diameter when tree is mature.

By contrast, Pseudopanax arboreus, P. laetus and P. lessonii are already ramified when young, forming secondary branches fairly early. They have a broader, bushier habit than other species.

In Pseudopanax ferox, leaves are very long and narrow, dentate on each side, which makes them resemble a saw. Its specific epithet ferox indeed refers to these teeth. Leaves are stiff and leathery, inclined downwards at about 45° or less, creating a very original shape, forming arrow-like lines upwards. This slightly evokes the pointed shape of Christmas firs. They give the impression that the bush grows upside down, head down. In Pseudopanax ferox, leaves are grey-bronze, with a paler central vein. Its uncommon foliage gives Pseudopanax an almost artificial appearance.

Pseudopanax ferox (photo Krzysztof Golik), and detail of its foliage / Pseudopanax crassifolius (photo Krzysztof Golik), and view of crown of an adult specimen, which ramifies

Leaves of Pseudopanax lessonii are very different. They are usually divided into five leaflets, sometimes with a fairly broad lamina, as in variety ‘Gecko Gold’. Thus, when divided into broad leaflets, leaves recall those of other Araliaceae, notably Fatsia japonica or Tetrapanax.

Leaves of Pseudopanax ferox have the peculiarity of changing shape as plant grows and ages. After 10–15 years, tree begins to form shorter, broader, dark green leaves without teeth. Juvenile leaf shape is actually a defence mechanism against herbivores, discouraging animals from eating them. When tree is older and leaves are higher up, they are out of reach and can therefore broaden!

Other species, with a more developed lamina (P. lessonii, etc.), sometimes display variegated foliage with yellow, as in Pseudopanax ‘Gecko Gold’ or Pseudopanax lessonii ‘Goldsplash’. Foliage can also be much darker, as in variety ‘Dark Star’.

Leaves of Pseudopanax are evergreen, remaining on tree through winter.

Leaves of Pseudopanax lessonii: type species, varieties ‘Gold Splash’ and ‘Dark Star’ (photo Stervinou)

Pseudopanax flowers usually in summer, between July and September, but flowering is of limited ornamental interest. Flowers are small, with four to five petals and are generally arranged in terminal umbels. They can be green, cream-yellow or purplish. Umbels of Pseudopanax ferox measure between 5 and 10 cm in diameter.

Pseudopanax ferox is dioecious. A male young plant and a female young plant are needed to allow fertilization and expect seeds.

After flowering, Pseudopanax produces (on female or hermaphrodite plants) small black–purplish fruits. They are rounded and measure between 3 and 8 mm in diameter.

Main varieties of Pseudopanax

Most popular varieties

Our favourite varieties

Pseudopanax ferox

It is the most common Pseudopanax in cultivation. It is very unusual, having linear, bronze-purple leaves, marked by numerous dentate margins, and inclined downwards. When mature, it produces another form of leaves, shorter and wider, dark green.

• Flowering time July, August
• Height at maturity 7 m

See the product sheet

Pseudopanax crassifolium

It has rigid, thin, dentate leaves directed towards the ground. They are brown-purple. It is a very graphic bush. Adult foliage becomes wider and shorter.

• Flowering time July, August
• Height at maturity 3,50 m

See the product sheet

Pseudopanax Goldsplash

Superb variety with green leaves variegated with yellow, divided into five more or less ovate leaflets. Very bright.

• Flowering time July, August
• Height at maturity 3 m

See the product sheet

Pseudopanax lessonii Dark Star

Leaves are thin and elongated, yet nevertheless wider than those of Pseudopanax ferox. They range in colour from dark green to purple, with a slightly paler central vein. This variety is ideal in a modern, graphic garden.

• Flowering time July, August
• Height at maturity 3 m

See the product sheet

Pseudopanax Gecko Gold

This variety has variegated green and yellow leaves, cut into fairly broad leaflets. Leaf shape and colours slightly recall a gecko's feet, which gave this variety its name. Appreciated for the brightness they bring.

• Flowering time July, August
• Height at maturity 3 m

See the product sheet

Planting

Where to plant?

Plant it in full sun or partial shade. Avoid scorching sun as well as deep shade. Bush produces more leaves when in a sunny spot. Plant Pseudopanax preferably sheltered from cold winds. It does not tolerate extreme temperatures, too cold in winter or too hot in summer. It prefers relatively mild, humid weather, as in New Zealand.

Pseudopanax grows in fairly ordinary soils. It appreciates humus-bearing, fertile soil, but will nonetheless tolerate poorer soils. We recommend planting it in a well-draining substrate. You can also plant on a mound or add coarse sand or gravel to soil to improve drainage. Pseudopanax dislikes waterlogging in winter, which will make it more vulnerable to cold and could cause roots to rot. However, soil should not be too dry either. Pseudopanax prefers rather acidic substrates and does not like lime.

Pseudopanax has the advantage of taking up very little space in garden. It has a thin, very upright trunk, sparsely ramified. In addition, with its very fine leaves, it does not really shade other plants.

If you live in a region with mild climate, you can plant Pseudopanax in ground. Otherwise, choose planting in a pot. You can then bring it indoors in autumn and return it outdoors in spring. It is also possible to to grow it year-round in a temperate greenhouse.

When to plant?

We recommend planting Pseudopanax in spring, from May onwards, once risk of frost has passed.

How to plant?

1. Dig a large planting hole, about twice the size of the rootball.
2. Replace some soil mixed with well-rotted compost and coarse sand, for drainage (You can also plant on a mound to help water run off).
3. Remove Pseudopanax from its pot, loosen the rootball slightly and place it in the planting hole. The collar should be at the same level as it was in the pot.
4. Refill with substrate all around.
5. Water generously.
6. You can install staking to help keep the bush upright.

Continue to water during weeks following planting.

You can also plant Pseudopanax in a large pot or planter. This will allow you to bring it easily under cover in autumn to protect it from cold.

1. Use a large pot with drainage holes in the base.
2. Place a layer of clay balls in the base.
3. Then add potting compost mixed with some well-rotted compost and coarse sand.
4. Plant your Pseudopanax.
5. Refill substrate around to secure and hold it in place.
6. Water generously.
7. Place the pot in a bright spot sheltered from cold winds.

→ Learn more about growing Pseudopanax in a pot in our advice sheet.

Pseudopanax lessonii (photo Krzysztof Golik)

Care

When planted in ground, Pseudopanax requires little maintenance. It is a robust plant and not very susceptible to pests and diseases. Although relatively drought-tolerant, water during planting year and thereafter in periods of prolonged drought. In a pot, water more frequently, on average once a week during growth. You can reduce watering in winter. When watering, prefer rainwater rather than mains water, which may be too hard.

If growing in ground, occasionally add some well-rotted compost at its base and lightly incorporate into surface soil by gentle scratching. In a pot, apply liquid fertiliser about once a month during growth. Reduce watering and fertiliser inputs in autumn and winter.

During early years, install a stake to help Pseudopanax form a straight trunk. We do not recommend pruning Pseudopanax ferox and Pseudopanax crassifolius, which are not ramified; but you can prune species such as Pseudopanax lessonii if they take up too much space in a greenhouse or indoors.

Protect Pseudopanax in winter with a frost protection fleece and a thick mulch around its base. If grown in a pot, move it outdoors in spring and bring it indoors in autumn to a frost-free shelter.

More information in our tutorial Pseudopanax: how to protect it from cold and overwinter it?

Propagation: sowing, propagation by cuttings

Pseudopanax can be propagated by sowing, propagation by cuttings or air layering. We recommend sowing.

Sowing

For sowing, use fresh seeds where possible, as their germination rate is higher.

1. Take a pot and fill with a mix of potting compost and coarse sand.
2. Firm slightly.
3. Sow seeds.
4. Cover with a thin layer of substrate.
5. Water.
6. Place pot under cover in a bright position and, if possible, at around 20 °C
7. Keep substrate slightly moist, but not waterlogged, until germination.

Propagation by cuttings

Pseudopanax can be propagated by taking semi-hardwood cuttings in early spring. However, as Pseudopanax ferox and P. crassifolius are not ramified in their juvenile phase, avoid taking cuttings from these species. Either wait until they are adult and take lateral branches, or reserve this propagation technique for other species.

→ Also read: How to propagate Pseudopanax?

Pairing Pseudopanax in the Garden

With its distinctive silhouette, Pseudopanax ferox is ideal for creating a modern, graphic garden. It adds strong vertical interest, helping to structure a border. Create a garden with clean lines and sober tones (green, bronze, purple, black, white, grey…). You can include ferns, horsetails, Alliums, Agapanthus, Japanese maples, bamboos… Also take advantage of fine, airy foliage of grasses. Pseudopanax can create a striking contrast when planted alongside lower-growing plants such as hostas, alchemilla, Hakonechloa macra, etc.

For a modern, graphic garden: Agapanthus ‘Black Magic’, Dryopteris cycadina, Pseudopanax ferox, Hosta ‘Allan P. McConnell’ (photo David J. Stang), Equisetum hyemale (photo Thayne Tuason)

Also feel free to pair Pseudopanax with other plants that have striking foliage! For example, plant Araucaria, Cotinus coggygria, Sambucus nigra, Grevillea… Consider decorative foliage of Fatsias and Tetrapanax. Pseudopanax is also ideal alongside ancient or primitive plants such as cycads, tree ferns or horsetails. Also think of the magnificent Wollemia nobilis, an ancient conifer from Australia.

You can use Pseudopanax ‘Gecko Gold’ or ‘Goldsplash’ to create a beautiful golden scene, combined with other yellow-leaved plants: Lysimachia nummularia ‘Aurea’, Carex elata ‘Aurea’, Agastache ‘Golden Jubilee’, etc. You can also achieve striking contrasts by planting a few dark-leaved plants: Ophiopogon planiscapus ‘Nigrescens’, Phormium ‘Dark Delight’, Heuchera ‘Obsidian’, Physocarpus ‘Midnight’…

For a garden of southern plants, especially other plants from Australia, New Zealand and South Africa. Think Protea, Phormium, Watsonia, Agapanthus, Callistemon… You can also grow restios, those perennials with long stems that resemble rushes or grasses. For advice on growing these plants, see our sheet “Plant and grow southern plants”.

Virginie offers more great ideas for pairing with Pseudopanax!