Golden Larch Bonsai Care Guide
Pseudolarix amabilis is not a true larch, but does share some of the same traits. Sometimes called by its old Latin name Pseudolarix kaempferi, it is native to southern and eastern mountain regions of China and may reach over 100 feet in its natural habitat. Golden Larch is the only species in the Pseudolarix genus. Parts of the tree are used in Bach homeopathic flower remedies, and it is one of the 50 herbs used in traditional Chinese herbology.
The small bright green leaves turn a vibrant golden yellow in autumn before falling off the tree. They lie in a spiral arrangement with wide spaces between them on the long shoots, and fall in dense whorls on shorter shoots. Small greenish-purple cones turn to golden brown in autumn. The red-brown bark turns grayish-brown over time, with ridges and furrows developing as the tree ages. This deciduous is favored by bonsai enthusiasts for its beautiful fall colors and low maintenance.
This species does well with heat and humidity, and in winter should have cool protection like an unheated shed or cold frame. The needles will grow longer in hot climates and stay shorter and more compact in cooler locations. It may be kept outside in summer, with afternoon shade provided to prevent scorch to leaves. The Larch can be kept inside if its environment is humid enough and provided with enough light (a south-facing window works well).
This conifer is ideal for those who find themselves over-enthusiastically watering their bonsai. It loves moisture and should typically be watered daily from spring through fall, and sometimes twice a day in summer. A humidity tray is the perfect way to keep the Golden Larch happy without having to soak the roots too often, risking root rot. On the flip side, this tree is not tolerant of drought so you cannot leave it for long periods unless you arrange for someone to care for it while you're gone.
From April to mid-July you should fertilize Pseudolarix once a week with a liquid organic feed mixed at a quarter of the normal strength. In late summer switch to a low-nitrogen formula in order to get the tree strong for winter.
Styles – this specimen is suited to most shapes except broom.
Pruning should be carried out in spring just as the buds are ready to sprout, but the branches can still be clearly seen and worked with. Just be cautious not to knock off any new bud growth in areas that you want to keep intact. Many experts believe that pinching needles is superior to clipping because it prevents browning of the tips, so use pinching to provide shape where you want it.
The Larch takes to wiring quite readily, just be sure to inspect the branches frequently as they thicken up fast and the wire could cut into them. Wrap older branches with raffia to protect the distinct, rough bark during wiring.
Seeds can be sown in moist soil in the early spring. In late spring you can try air layering – remove a small strip of bark from the chosen branch and wrap the cut area with a small bag of moist peat and sphagnum. Keep consistently moist for 6-12 weeks, then check for roots. Remove the cutting once the root system is developed enough to sustain it in a pot of its own. Leave the peat mixture in place when transplanting.
Unlike many bonsai, the Golden Larch will need to be repotted once a year. It does not like being root-bound and should be transplanted in late February to early March, as soon as the dormant buds get shiny at the tips (this means the needles will break out soon). Prune any discolored or unhealthy looking parts of the root ball and transplant into an all-purpose bonsai soil rich with organic matter.
Insects/Pests & Diseases
While this is a hearty bonsai that doesn't succumb easily to diseases or pests, most bonsai can become vulnerable at some point especially if weakened from stress. Aphids or scale are potential concerns.
Keep an eye out for tiny, soft, pear-shaped bugs grouped in clusters on foliage – these are aphids and can sometimes be removed with a firm but gentle spray of water, or a mixture of one teaspoon dish liquid to 32 oz. of warm water, sprayed on until runoff occurs. Rinse with plain water and repeat if necessary.
Scale are little black or brown bumps on branches or leaves and must be removed manually with the tip of a sharp knife. They may also be dabbed with a cotton swab that has been dipped in rubbing alcohol. Repeat to remove the eggs that were harbored under the shells.
A bi-monthly treatment with a non-toxic insecticide spray can help keep pests away. Feed, water, and expose your bonsai to proper light levels and it will be better able to stay healthy and resistant to problems.