"Upon finding that I work as a professional bonsai artist, many people will remark that they once had a bonsai, but it died and with some regret, they gave up".
Based on the Bonsai Basics section of the hugely successful Bonsai4me.com website and an e-book of the same name, 'Bonsai Basics: The Foundations of Bonsai', written and developed over the past 15 years is out now!
All copies are signed by the author.
Acer campestre is the only truly native maple in Europe and is often found growing in broad-leaved woods on lowlands and hills. Field maples are very vigorous growers up to around 8metres in height and can quickly form stout trunks with heavily patterned, rough bark. Leaves are 3-lobed, dark-green above and blue-green underneath and grow to around 9cm in length on specimens grown in the ground. However with bonsai cultivation, leaves can be dramatically reduced to a 1/3 of this size. Acer campestre develop impressive autumn colouring (as with most other Acer species) as leaves turn bright yellow and orange. New leaves in Spring and (to a lesser extent) through the year have a red hue to them. Flowers appear in May but are insignificant and are followed by small red fruit.
Bark is a buff brown/grey and is smooth when young but develops light coloured fissues with age. Field Maples are very long-lived trees, reaching ages of 400 years or more. New growth sometimes develops narrow ridges or cork 'wings' running the length of the trunk (very similar to some Ulmus and Euonymous species).
Growth is coarser than Acer palmatum or A. buergerianum. However in the UK, the Field Maple is the strongest and most vigorous of the three species. Thick trunks can be developed very quickly in the ground; it is not unusual to see an increase in trunk girth of over 1" a year in field grown material, with new shoots reaching over 6-7ft within the space of a growing season. As with A. palmatum and A. buergerianum, wounds heal over very quickly, particularly on field growing trees.
campestre can be difficult to locate in UK garden centres but
are very often found at hedging nurseries as well as from the
BONSAI CULTIVATION NOTES
POSITION Full sun throughout the growing season. Field Maples have much stronger leaves than Acer palmatum. Weak rooted specimens may suffer from leaf scorch in Summer and should be afforded some protection from the sun.
Very tolerant of frost but some frost protection is required when temperatures drop below -10°C or for trees in very small pots.
tolerant of quite dry soils, Field Maples prefer damp conditions
in a well-drained soil for maximum health and vigour. Do not overwater.
FEEDING Feed every two weeks from bud-burst to leaf-fall. Trees in development can be heavily fed to increase growth rate and trunksize but feed developed bonsai gently to reduce the coarseness of new growth.
REPOTTING Every one to two years as buds extend. Developed Field Maples are repotted less frequently in an effort to reduce leaf-size and the coarseness of new growth.
Field Maples are
very tolerant of heavy root pruning and easily form dense, fibrous
root systems suitable for bonsai cultivation.
PRUNING Trim back new shoots to one or two pairs of leaves throughout the growing season unless branch extension is required. Remove all shoots with long internodes. Shoots normally regrow after only 2 or 3 weeks.
Prune large branches or trunk-chop either after leaf-fall to avoid excessive sap-bleeding in early Spring or at midsummer to take advantage of very quick wound-healing times.
Twig denseness and ramification can be increased dramatically using defoliation techniques and by removing large leaves and coarse growth throughout the growing season.
further pruning details please refer to the Advanced
Acer palmatum article at Bonsai4me.com. The guidelines on
Trumming, Defoliation,Branch Pruning, Pinching Back, Internode
Distances, Use of Sapdrawers and Positioning as all as equally
applicable to Acer campestre as they are to Acer palmatum.
WIRING As with all Acer species, the bark of A.campestre is very sensitive and marks easily. Field Maples also thicken relatively quickly and wire should be checked on a weekly basis to make sure it is not cutting in.
Growth is surprisingly
brittle; particularly that of new, green growth and care must
be taken when bending branches.
PROPAGATION Sow seed outside as soon as ripe in Autumn. Softwood cuttings in Summer, very easily air-layered in late-Spring; branches/trunks of 3-4" or more will root with ease.
PESTS AND DISEASES Aphids, mites, scale insects, caterpillars and leaf scorch.
STYLING The Informal broom form is closest to the species' natural habit, also suitable for all other forms except Literati. Medium to large sizes are preferable but can be grown in smaller sizes with leaf-reduction.