Synonyms

Acer palmatum purpureum

Family

Aceraceae

Common name/s ?

Japanese maple

Skill rating

Easy

Origin

Japan, where it grows in lowland and mountain woods.

Type of plant ?

Deciduous tree or shrub – it can be grown as (and classified as) either.

Hardiness zone ?

RHS zone

Hardy

EGF zone

H4

USDA zone

5-8

Eventual size

It will reach a height and spread of 6 metres, or a little more.

Growth rate ?

Slow growing.

Shape it grows into

It has a bushy, rounded habit and can be grown as a tree or a domed shrub.

Season/s of interest

From spring to autumn for the leaf colour. Flowers appear in April/May followed by the winged fruits in summer and autumn.

Where to grow it

Happiest in full sun.
Prefers well drained to moist soil.

Happiest in full sun (though not where it will get direct sunlight all day, which can cause leaf scorch) and will tolerate part shade. It will be happy on any soil type including chalk, clay and sand. The autumn colours will be best in neutral to acid soil. It prefers a sheltered location to protect it from the worse of the elements.

Acer palmatum 'Atropurpureum'

Features

The purple, paired leaves (greener the less sun getting to them) have 5 pointed, deep lobes with sharply toothed margins and they turn brilliant red in autumn. Buds are ovoid in shape, 2 to 3cm long and reddish in colour. Spring flowers are small and red/purple before the red, winged fruits (“samaras“) appear hanging in clusters in summer/autumn.

What to use it for

A good, and commonly used, tree for a small to medium size garden which can provide shade in the summer before its glorious autumn display. It suits most styles of garden, is low maintenance and can be an interesting focal point. It suitable for being grown in containers (so long as it is kept well watered) and could also be effective in a large rock garden.

How to look after it

Ensure that it is watered in drought conditions, particularly in the first few years of growth.

How to prune it

While establishing an Acer palmatum the plant should be staked to provide it with additional support and pruned to remove any badly placed or crossing stems. Once established pruning should be kept to the bare minimum – only removing dead, damaged, diseased and crossing stems.

Any pruning should be done in winter when the tree is completely dormant. If done at any other time the plant will ‘bleed’ sap and be weakened as a result. Minor pruning of thin stems could be undertaken in late summer or early autumn if necessary.

How to propagate it

Propagate by softwood cuttings in mid-spring (you may need to bring the parent plant under cover to get it to put on enough growth to take the cutting this early) or early summer. Alternatively carry out simple layering in mid/late autumn or early spring.

If you have the skill, grafting can be done in late winter or summer (using a side veneer graft so the scion is not pushed off by the rising sap).

Common problems

Leaf scorch due to a lack of soil moisture or too much exposure to the elements (eg intense sunlight, high winds).

Aphids and horse chestnut scale can be a problem, as can verticillium wilt.

Other useful information

The ‘palmatum’ species of acers are so named since their lobed leaves resemble outstretched hands, ie ‘palms’.