Japanese White Pine Bonsai Care Guide
Japanese White Pine, or Pinus pentaphylla, is also known as Japanese Five Needle Pine (Pinus parviflora). This native of Japan can grow in nature to be 50 feet tall and is a favorite bonsai subject around the world as well as in its homeland.
The needles of the White Pine are approximately one to one and a half inches in length and grow in groups of five in bright green to blue-green tufts on the branch tips. The textured brown bark is another desirable feature making this a favored bonsai species.
This evergreen craves a temperate climate where it can experience all of the temperature changes that are required for it to thrive. It prefers to be an outdoor tree with exposure to full sun.
Pinus pentaphylla can be permitted to become dryer than some bonsai. The roots should not be saturated when the plant is watered; instead, water from the top of the soil so that the moisture can work its way through the pot gradually. Well-draining soil is vital to pine trees. In addition, you will want to take into consideration the local climate – factors like humidity, direct sunlight, and temperature – when settling on a watering routine. You can also use a moisture meter to take the guesswork out of watering your bonsai.
Once new growth appears in the spring, give your White Pine bonsai an organic, slow-release fertilizer. Continue this feeding regimen throughout the growing season. Chelated iron may be administered two or three times per year. Alternatively, if using a chemical fertilizer, choose an acidic formula, feeding it bi-weekly and diluted to half-strength.
Popular Styles – this species can be shaped into many different bonsai forms, however it is most frequently seen as formal or informal upright. The natural lean of the White Pine trunk lends itself to slant. A striking canopy can be made of the dense foliage that adorns this tree.
Pluck needles by hand throughout the growing season. In autumn the branches may be pruned. Pinch new growth in the spring, removing to a third of the original length of the growth. Every other year in late spring, pinch off all new growth in order to encourage new buds to form and as a way to force growth in specific areas to achieve your desired shape.
Wiring may be done on the Japanese White Pine, and it should be carried out in autumn at the same time as hard pruning. The wires can remain on the tree for six to eight months, with close monitoring to make sure they aren't cutting into the bark.
Japanese White Pine can be propagated by way of layering or sowing seeds. To grow from seed, soak them for a couple of days and throw out any seeds that float in the water, as they are impotent. Place the good seeds in a moist rooting medium like sand and keep in a cool place for a couple of months before potting.
Trees that are younger than ten years old can be repotted every two or three years. If older than ten, the bonsai can be repotted every three to five years. This should be carried out in the spring, prior to the candles opening, or after the hottest summer weather is over – late summer to early autumn. Pines have a more extensive root system than some species and so need a deeper pot than other bonsai. The deep pot also helps prevent strong winds from uprooting the tree due to its dense foliage.
Do not be too aggressive with root pruning. Pines like a judicious, conservative root pruning approach. They also should not be bare-rooted due to their symbiotic relationship with Mycorrhiza, a fungus that is necessary to the health of the tree. Repot the White Pine into a coarse, well-draining soil. One that is made up of most to all inorganic material works very well.
Insects/Pests & Diseases:
Pinus pentaphylla can be vulnerable to the typical range of pine enemies, such as aphids, mealy bugs, and red spider mites.
Aphids and mites can be washed off in a stream of water, or if necessary a gentle insecticide may be used.
Mealy bugs may be seen at the bases of leaves, appearing as little white masses, or they may be seen on the roots during repotting. Mealy bugs should be treated with insecticide designed solely for that specific pest.
White Pine, like most pines, may also fall prey to the fungus called needle cast. This condition may cause browned needle tips or discoloration in a ring pattern around the shafts of the needles. While the disease may be successfully treated with special products, it's much better to use a year-round preventative spray to completely avoid this problem.