This is a tree whose beauty is legendary, yet it suffers from some neglect as bonsai. There are many species of larch to choose from and available in Europe are Larix decidua, the European larch; L. kaempferi, syn. L. leptolepis, the Japanese larch and L. Eurolepis, the Dunkeld larch: a hybrid between the Japanese and the European larch. There are also various dwarf forms of the species that look promising.
- Common Name: Larch
- Genus: Larix
- Higher Taxon: Pinaceae
- Species: Decidua: leptolepis, etc
- Skill Level: Beginners to advanced
- Soil type: Larch is not keen on dry shallow chalk soils or boggy sites.
- Flowers: Trees are monoecious. Female strobili of red, pink, yellow or green, and the greater number of yellow male strobili, stud the branches in early spring. The cones that follow may consume the vigour of the tree causing dieback if they are not thinned out.
- Leaves are linear and borne in rosettes from short spurs. The fresh green of the spring leaves later turns a rich green and finally to a buttery yellow or reddish gold before they drop in autumn.
- Bark: The bark on new shoots is green, mellowing to brown and then grey with age. The old bark becomes coarse and fissured. Tree forms are diverse and branches become upswept and often have great character.
Tips: Go easy with the nitrogen and avoid a root-bound condition leading to the drying up of tissue and dieback in the branches. This reaction to root binding reflects the intolerance larches have to heat and their resultant unhappiness, so use light shade.
Nitrogen pumps the wood up like the physique of a steroid happy athlete! Use fish emulsion and seaweed, and if you want to use nitrogen, dilute it way down — quartering dosage is not a bad way to go.
Becoming far more easily obtainable these days, nursery stock is often a good source for material, particularly for single trunk and group styles. Forestry outlets are also good resources.
Aborted plantations, the Alps, and wet forestry areas are all good places to look. If you want your tree to have the best chance of survival you must have good aftercare — a humidity tent at least and shade on hand.
If taken in March,branch ends from bonsai will sometimes root well and yield magic little Shohin size plants. Otherwise, grow from seed.
Can be done using the wire tourniquet method, but it is liable to be slow.
Light shade is best in summer. Provide good light in spring, autumn and winter but protect from frost contact.
Pinch soft shoots back to two buds after they have grown out and extended somewhat. In August, tip branches back to side growth and if the tree has become ragged, trim branches hard back to force inner buds and compact growth. Sometimes deep pruning is used to arrange the branches and create interest in the overall shape. Deep pruning can lead to the production of a false system of tight bud rosettes like a witches broom. Always remove buds growing in branch forks.
Repot every two to three years. Older trees are repotted on demand, as root growth is slower. Repot as the buds are growing shiny and before you see green, NOT later.
Wire in winter and then keep frost-free. Wood is soft but old bark is easily marked, so wire loosely.
Avoid any soil likely to clog up the roots. An ideal mix would feature a lot of gritty gravel and light organic material in a ratio of around 70% to 30%.
Pests and Diseases:
Adelgids are the most common pests. The ones that attack larch are covered with white woolly wax and are associated with honeydew and sooty moulds. Treatment is by contact spray using malathion. A winter spray with dormant oil will take care of any over wintering insects.
Larches prefer ‘damp’. Avoid water logging, avoid drought and maintain a constant dampness. Larches need airflow and good light but not so much they dry out. Shade net is a useful device in providing optimum conditions to maintain dampness. Do not water spray young leaves if you want to avoid palm-sized foliage! Wait until leaves have ‘set’ before sprinkling them.
Formal, informal, leaning, windswept, driftwood, literati, semi cascade, raft, root- connected, twin trunk, triple trunk, group and miniature bonsai — larch is versatile!!
A must for any collector, easily trained and offering a pleasing image, even as a tiny plant. As an older tree, the larch is outstanding in the quality of age it can convey as bonsai. Overall, it is a very easy and rewarding tree as bonsai.
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