Chinese Juniper Bonsai Care Guide
China, Japan, Korea and wider over east Asia
Evergreen. Scale or needle-like foliage
Forms a small tree / large bush in the wild. Mature foliage is scale-like while immature foliage is more needle-like.
New plants can be cultivated easily from semi-hardwood cutting taken in the autumn. Heel cutting work well, placed into horticultural grit-sand.
Grown in a variety of sizes from very small to extra-large. When grown as very small bonsai, individual shoots are taken to represent whole branches.
Popular forms for bonsai include Shimpaku and Itoigawa, which tend to be available from bonsai nurseries.
Numerous other forms are available from garden centres and plant nurseries.
Juniper bonsai are frequently seen with areas of deadwood (jins & sharis) which are often bleached white.
Junipers are crafted into a variety of bonsai styles, included informal upright, slanting, semi-cascade, full-cascade. They are also found in twin and triple trunks, rafts and groups. Less commonly found in formal upright and broom styles.
Outdoors only. Grows well in full sun. Slight shade in full summer is suggested, as the strong sun causes the foliage to yellow a little.
Protection from frost is recommended where temperatures drop down below minus ten degrees. Being evergreen, they should not be over-wintered in sheds or other dark storage areas as it is believed that they still need light during the winter months.
I have found that they don’t like being kept in greenhouses in summer, the heat can affect the trees and cause them to develop yellow patches.
Water daily in hot weather. Keep evenly moist at other times. Rainwater is better in hard water areas, as the tree prefers a slightly acidic soil.
Pruning, Styling & Watering
Maintenance pruning is undertaken by pinching the scale foliage. Take the foliage between your thumb and forefinger and give it a gentle pull. The growth tips should come off between your fingers. You hold the branch with your other hand to reduce the chance of you snapping it. This process should be done every couple of months from spring to autumn. Don’t try to pinch out more than will come off relatively easily, as this will encourage the tree to respond by putting out juvenile needle growth.
Junipers can be wired at any time of year. The wires will need to be kept on the tree for some time – a year is not uncommon, though do keep an eye on the wires to ensure that they are not biting into the trunk.
We feed our junipers with a slow release fertiliser, which is not particularly strong at NPK 5-5-5, from spring to autumn.
Chinese Junipers are tolerant of tight root masses. The tree can cope with a dense root ball and does not need to be repotted very frequently. In fact keeping the tree almost pot bound helps to keep growth very tight. Please don’t take this advice as a recommendation to neglect the roots, we’re just saying that junipers can be grown slight more tightly than other bonsai trees.
Younger bonsai should be repotted every three to five years. For mature specimens, repotting is less frequent and only takes place when necessary.
Pot into a free-draining soil mixture, containing some clay granules mixed with harder media such as granular pumice, grit or kiryu. We use mixture of akadama, pumice and kiryu.
When repotting, remove about 30% of the root mass. Repotting should take place in the spring.