<i>Aralia</i>: planting, cultivation and care

Botany

Aralias include between 70 and 80 species of trees, bushes and herbaceous rhizomatous perennials. They are mainly found in Asia and North America. Aralia elata is native to eastern and northern Asia (Japan, Korea, Siberia, northeast China), while Aralia racemosa and A. spinosa come from North America. In the wild, aralias grow mostly in mountain forest. The most commonly cultivated species in gardens is Aralia elata, a deciduous tree with very decorative, divided foliage formed of many leaflets. It is vigorous and fairly hardy, but dislikes late frosts, which can damage its young shoots.

At a botanical level, Aralia has given its name to its own family, Araliaceae, which includes more than 1,500 species. This family also groups other plants prized for decorative foliage: Fatsia, Schefflera, Cussonia, Tetrapanax… but also, more common and less exotic, ivy (Hedera helix)! In fact, flowers and fruits of Aralia californica resemble those of ivy. Ginseng (Panax ginseng) also belongs to this family.

In French, Aralia elata is called Japanese angelica-tree or Chinese angelica, because it comes from Asia and its foliage resembles that of angelica; but Fatsia japonica is commonly called Japanese aralia… Beware confusion between these two genera! Only scientific names in Latin reliably identify these plants. Likewise, Polyscias, a houseplant in Araliaceae, is sometimes called “Balfour’s aralia”. Aralia spinosa is also known as devil’s walking-stick because of its thorns! In Latin, specific epithet A. elata means “tall”, while A. spinosa means “spiny”.

Aralia cordata: Botanical illustration

Generally, Aralia elata reaches 5–6 m in height, but can ultimately grow up to 10 m. It grows fairly fast, and its canopy can be as wide, because habit is rather spreading. It has a distinctive silhouette: initially upright, it later develops a very elegant, umbrella-like form. It is interesting to grow it as a specimen to fully appreciate it. Trunk is grey and rough, and bears thorns. Branches are fairly thin and elongated, long and little ramified. Depending on training, Aralia can form a single trunk or several (if you allow suckers to develop). When it forms several trunks, effect is more natural and light, in coppice shoots.

But not all aralias are shrubby or tree-like; some are herbaceous perennials that do not exceed 1.5–2 m in height. Aralia racemosa is a large, spreading and ramified perennial, much lower than other Aralia. A. californica is also an elegant perennial with luxuriant foliage.

Aralia bears very large divided leaves, composed of numerous leaflets. They are highly ornamental and give plant an exotic, luxuriant aspect! A. elata earned its common name Japanese angelica-tree, or spiny angelica, because leaves resemble those of angelica, which also has finely divided foliage. Aralia leaves are bipinnate, twice divided, and borne on a slightly reddish petiole. They are spiny, bearing small thorns along foliar axes. Leaves of Aralia elata are pubescent on lower surface. They are arranged in tiers and unfold at top of bare branches, creating an umbrella-like aspect. This inspired cultivar names such as ‘Golden Umbrella’ or ‘Silver Umbrella’.

Leaves of Aralia can reach between 1 m and 1.20 m in length! Leaflets composing them are small and ovate, with lamina margin slightly dentate. They measure between 6 and 10 cm in length. A single leaf can include 80 leaflets!

Aralia leaves are usually green, paler beneath. However, several cultivars offer unusual colours! Aralia ‘Sun King’, for example, stands out with superb golden foliage. Leaves can also be variegated, with lamina margin irregularly marked with cream-yellow in ‘Golden Umbrella’, or white in ‘Silver Umbrella’. These colourful-leaved varieties are valuable for bringing light into a shady, woodland garden.

In autumn, leaves of Aralia elata turn yellow–orange, even deep purplish red. Aralia is one of those plants that mark year’s end with flamboyant hues!

Aralia elata is deciduous: leaves take beautiful autumn colours, then fall… New leaves appear in spring. In general, most aralias cultivated in gardens are deciduous (A. spinosa, A. californica, etc.), but in nature there are also evergreen species.

Leaves of Aralia spinosa (photo FD Richards), those of Aralia cordata ‘Sun King’, and those of Aralia elata ‘Silver Umbrella’

Aralia elata flowers in late summer–early autumn, around August–September (Aralia spinosa flowers a little earlier, sometimes as early as late spring). Plant then bears large, long inflorescences with a light, airy, wispy appearance. These are panicles of umbels, composed of numerous tiny flowers, appearing on current-year shoots in terminal position. Panicles of Aralia elata often measure 40–60 cm in length; those of Aralia spinosa are slightly larger. Flowering is white or cream-white, sometimes slightly greenish, and flower stems are reddish.

Individual flowers are minute, about 3 mm in diameter, but very numerous and gathered in large inflorescences! Each small flower has five petals and also five stamens that bear pollen. Flowers are melliferous, attracting pollinating insects, notably bees.

Flowering of Aralia elata (photo Katja Schulz), and of Aralia californica (photo Udo Schmidt)

They are followed by small globose fruits that appear in autumn. These are rounded drupes measuring 4–6 mm in diameter, usually black or dark purple. They are much appreciated by birds, which eat them and thus ensure seed dispersal (zoochory). You can harvest fruits to recover seeds inside and propagate Aralia by sowing. However, these seeds take quite a long time to germinate (…up to six months!)

Species Aralia racemosa, commonly called clustered aralia, is decorative in the garden for its superb clusters of dark red–black fruit.

Aralia is an interesting plant for biodiversity, as its flowers are melliferous and its fruits are enjoyed by birds.

Fruits of Aralia cordata (photo Averater), and of Aralia racemosa (photo Kristine Paulus)

Aralia elata produces suckers: it sends up shoots, new shoots that develop from roots. In this way it can spread and colonise ground. It is possible to propagate the plant by lifting and replanting suckers.

Main varieties of Aralia

Most popular varieties

Our favourite varieties

Aralia elata

Most commonly cultivated species! Valued for its majestic, spreading habit and its large, beautiful green leaves, very finely divided. In late summer it bears long panicles of white flowers with a feathery appearance.

• Flowering time October, November
• Height at maturity 5 m

See the product sheet

Aralia cordata Sun King

This variety is remarkable for its superb golden foliage, which brightens shaded corners of the garden! It also produces creamy-white flowers, followed by small black fruits. Young shoots are also edible.

• Flowering time September, October
• Height at maturity 1 m

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Aralia elata Silver Umbrella

This aralia has beautiful divided leaves, composed of leaflets whose green lamina is irregularly marginate with white. One of the most interesting varieties, offering a majestic silhouette and striking foliage, ideal for brightening a somewhat shady area of the garden.

• Flowering time September, October
• Height at maturity 5,50 m

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Aralia elata Golden Umbrella

Valued for large leaves composed of green leaflets marginate with cream-yellow. Also produces superb white inflorescences, followed by decorative fruits. Recipient of the Royal Horticultural Society's Award of Garden Merit (RHS).

• Flowering time September, October
• Height at maturity 2 m

See the product sheet

Aralia spinosa

This aralia has very large, deeply divided green leaves and in summer bears broad terminal inflorescences, white and very light. Also known as Spiny Angelica or Devil's walking stick. Closely resembles Aralia elata.

• Flowering time July to September
• Height at maturity 6 m

See the product sheet

Aralia californica

Very different from other aralias, this species is not a tree but a large, majestic perennial! Its large, highly decorative leaves have a lush, exotic look. In summer it also produces a beautiful white flowering, followed in autumn by globose, black-burgundy fruits.

• Flowering time August, September
• Height at maturity 2 m

See the product sheet

Planting

Where to plant?

Plant Aralia preferably in partial shade, as it appreciates bright situations but does not like scorching sun. Ideally it should be shaded at least during the hottest hours of the afternoon. Exposure also depends on your geographic location: you can place it in sun if you live in northern France, but prefer partial shade in the south. In summary, avoid extremes: scorching sun as well as thick, dense shade.

Aralia prefers soils rather rich in organic matter, fertile, humus-bearing. When planting, we recommend mixing some well-rotted compost into the soil. The substrate must be light, deep and permeable; avoid soils that are too heavy and compact. Aralia also likes cool, slightly moist ground. You can therefore place it near a water feature or pond. However, the substrate must remain free-draining. Aralia can tolerate some drought.

It is also important to choose a spot sheltered from wind, as wind can damage the foliage.

On the other hand, Aralia are not very sensitive to soil pH; they can grow on acid or limestone soils. In general, Aralia is not a demanding plant and can adapt to most garden soils. It also tolerates urban pollution fairly well.

Over time, Aralia takes on a majestic, very elegant silhouette. It is interesting to plant it as a solitary specimen, in the middle of a short grass meadow, to really show off its architecture! Moreover, planting it as a solitary specimen makes it easy to spot and remove suckers as they appear (which can be more problematic if you plant it right next to a border).

As Aralia grows fairly quickly and spreads by suckers, it can be used to reforest an area rapidly. It provides a tree cover to a garden or space that was previously open and treeless.

Do not hesitate to place Aralia in somewhat remote areas of the garden that you leave wild and visit infrequently. You can let it develop naturally and spread a little; it will thus form a small grove.

When to plant?

You can plant Aralia in autumn (September–October) or in spring (around April). Plant when weather is relatively mild, outside periods of frost or extreme heat.

How to plant?

1. Start by placing the root ball in a tub of water to rehydrate it.
2. Dig a hole large enough, about three times the size of the root ball.
3. Add some well-rotted compost mixed with garden soil.
4. Place the root ball in the planting hole. Ensure the trunk is upright and that the soil level matches the original potting medium level.
5. Replace soil around the plant, and firm down lightly.
6. Water generously.
7. You can apply a mulch so the soil stays cool longer.

Continue to water in the weeks following planting.

Aralia elata

Maintenance, pruning and care

Aralia does not really require maintenance, except perhaps the occasional removal of suckers that appear. It naturally adopts an elegant, well-structured habit and does very well without pruning, but you can also intervene occasionally to remove a few damaged or misshapen branches, as well as suckers.

If from an early age you regularly remove suckers, your Aralia will form a single trunk. If, on the contrary, you leave some, it will produce several trunks and take a lighter, more natural silhouette, in coppice shoots. Pruning of suckers and branches will therefore influence the plant’s overall silhouette.

You can water it during the year of planting and in case of exceptional drought. Likewise, you can from time to time place a little well-rotted compost at its feet to enrich the soil, and work it in superficially by light forking. However, if ground is too rich and fertile, Aralia may become more fragile and less hardy.

Aralia is not susceptible to diseases and pests. It is sometimes attacked by aphids, but the impact on the plant remains fairly low.

Propagation

We recommend propagating Aralia by taking the suckers it produces. It is also possible to harvest the seeds and propagate by cutting the roots. Horticultural varieties with variegated and colourful foliage are usually propagated by grafting.

Taking the suckers

Aralias regularly produce offshoots, or suckers, which develop on the roots of the parent plant. It is possible to separate them to obtain new young plants. Do this preferably in late winter, around February or March.

1. Choose a well-formed offshoot that has grown next to an Aralia.
2. Dig down to expose the root system.
3. Cut the roots that connect it to the parent plant.
4. Lift the offshoot, keeping as many roots as possible.
5. Prepare the ground and replant it in a new position.
6. Water generously.

Propagation by root cuttings

Aralia can be propagated by root cuttings in winter (around December–January).

1. Dig at the base of an Aralia to expose the roots.
2. Take a root segment about 8 cm long, cutting it cleanly.
3. Fill a pot with a mix of potting compost and sand.
4. Place the root segment vertically in the growing medium; the top of the root should be level with the surface.
5. You can then water lightly.
6. Place the pot under a cold frame.

Sowing

You can harvest the fruits to recover the seeds they contain and sow them in autumn. Preferably use fresh seeds, recently harvested. They must be cold-stratified, for example by placing them in the refrigerator for about 4 months. You can then sow them.

1. Fill a pot with a fine, light seed compost.
2. Firm down so the surface is even and uniform.
3. Sow Aralia seeds.
4. Cover lightly with a layer of sieved compost, then firm down.
5. Water with a fine spray.
6. Place the pot in a bright position, out of direct sun, at about 20 °C.

Seeds take a long time to germinate (up to six months), so be patient. Once seedlings are large enough to handle, pot them on into individual pots. Keep them under cover over winter, at least for the first year. You can then plant them out in the garden (preferably in spring).

Association

With their large, deeply divided leaves, Aralias fit well into exotic-style gardens. You can combine them with other generous, large-leaved plants such as Datisca cannabina, Gunnera, Fatsia japonica, Tetrapanax, Astilboides tabularis… Don’t hesitate to add bamboo and lianas: enjoy Akebia quinata, passionflowers… This will create a lush, jungle-like setting! We particularly recommend using Aralia californica, this majestic perennial with imposing foliage. Also discover the surprising flowering of Arisaema!

Aralias can be integrated into an exotic, luxuriant garden evoking a true plant jungle! Passiflora_caerulea (photo Fdbrumbl), Gunnera manicata (photo Dezidor), Aralia californica (photo Plant Image Library), Akebia quinata (photo Salicyna), Datisca cannabina (photo Peganum), and Arisaema triphyllum (photo Jason Hollinger)

Aralias are also perfect in shady gardens to recreate a very natural woodland understorey (especially when they form several slender trunks and adopt a coppice-shoots habit!). Combine them with hostas, ferns, brunneras, Solomon’s seal, sweet woodruff, etc. Discover the superb foliage of Paris polyphylla! Also enjoy the flowering of Anemone nemorosa, bluebells (Hyacinthoides non-scripta), Corydales, Dicentra spectabilis, epimediums, Geranium nodosum… to bring small touches of colour! Also discover Cornus canadensis: groundcover with white flowers and decorative foliage. You will obtain a natural, fresh garden that feels like a walk in the wood! Favour woodland plants that naturally occur in woods. For this type of garden, choose plants that do not require much maintenance, and small flowers that can naturalise. Regarding Aralias, we recommend variegated varieties, as they are ideal for bringing light into the understorey! They will brighten the darkest areas of your garden.

They also find their place in a naturalistic garden to recreate an understorey atmosphere. Geranium nodosum, Brunnera macrophylla (photo Agnieszka Kwiecień, Nova), Aralia spinosa (photo Fritz Flohr Reynolds), Hyacinthoides non-scripta (photo Olivier Pichard), and Polygonatum latifolium (photo Radio Tonreg)

Also consider pairing Aralias with other plants that take beautiful autumn colours. Some trees and bushes offer remarkable late-season foliage in shades of red–orange–yellow–purple–bronze… Take advantage of Nandina domestica, Japanese maples, Parrotia persica, Cercidiphyllum japonicum (caramel tree)… and do not forget common dogwood, Cornus sanguinea, which also displays superb red-orange bark in winter. For a lovely autumn atmosphere, you can also pair Aralia racemosa with other plants that produce decorative fruit: spindle, Callicarpa, Viburnum opulus, Sorbus aucuparia… This will also have the advantage of attracting birds to the garden!

With its elegant, clean-lined silhouette and sparse branching, Aralia brings a Japanese touch (especially since A. elata originates from Asia and naturally grows in Japan!) It can easily be integrated into a zen garden. Pair it with Japanese maples, flowering cherries, Cornus kousa, Hakonechloa macra, Hostas, horsetails, bamboo… You can add some cloud-pruned pines, and possibly a few structural decorative elements: lanterns, arbor, fountain, wind chime, jetty, stepping stones… but without excess. Also leave plenty of space for mineral elements, incorporating gravel and a few rocks with interesting shapes. This will create an atmosphere conducive to meditation.

Also remember Aralia is magnificent as a solitary specimen! This really showcases its silhouette while making it easy to control suckers.

Did you know?

• Edible and medicinal plant

Several species of Aralia are edible and eaten in some Asian countries. Young shoots of Aralia cordata are mainly used (but A. elata is also edible); they are harvested in spring while still tender. They can then be blanched and eaten like asparagus, or fried. Moreover, Aralia cordata is also called Aralia edulis (synonym), and this species name, edulis, means “edible” in Latin. Likewise, the fruits of Aralia racemosa are edible! The root of this species is also medicinal, effective against breathing conditions, asthma, colds, coughs… It is mainly used in homeopathy.