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Features
This is a great value tree for a smaller garden. In spring it bears inconspicuous, pendulous, yellow/green flowers which develop into green samara fruit in summer, falling in autumn. The leaves are divided into three leaflets, each dark green on top and silvery-grey with hairs underneath. In autumn the leaves turn bright red and orange. The falling of the leaves in the autumn reveals the spectacular stems, which have orange-brown, papery bark that peels off and looks fabulous when caught in midwinter sunshine.
What to use it for
A great feature plant for a focal point, particularly to add winter interest. Is good for a low maintenance garden, once the work has been done to train it to a good shape.
How to look after it
When first planted the tree should be trained to form a well-shaped single or multi stemmed plant – we have given it a ‘moderate’ skill rating to reflect this work. It would also benefit from a balanced fertiliser being applied as top dressing in the spring while it is establishing.
Once established, however, little work is required to maintain it.
How to prune it
This tree can either be trained as a central- standard until it reaches 1-1.5m in height, or as a multi-stemmed tree. Once established it will require minimal pruning, just to remove diseased, damaged, dead, weak or crossing stems. Any pruning should be done in winter when the tree is fully dormant – maples bleed sap profusely at other times of year. Minor cuts can be made in late summer or early autumn.
How to propagate it
Softwood cuttings can be taken in early summer.
If several Acer griseum are planted together then it may set viable seed (if you have a sole specimen then the seed is unlikely to germinate) which can be sown fresh outside or in a cold frame, or stored in moist vermiculite, coir or peat in the refrigerator for spring sowing (if doing the latter, check regularly and sow any which germinate in the fridge). Seeds will germinate at 10-15°C. It is not uncommon for them to germinate in the second year after sowing, rather than the first.
Simple layering can also be carried out in mid/late autumn or early spring if the ground nearby the tree is suitable.
Common problems
Acers may be prone to infestations of aphids or horse chestnut scale. They may also be susceptible to tar spot, sooty bark disease, verticillium wilt and winged cork.
Other useful information
This Acer is named ‘griseum‘, meaning grey, due to the silvery-grey appearance of the leaf undersides.
Acer griseum has been given the Award of Garden Merit by the RHS.
