As one of the 110 species included in the Pinus genus, the Japanese Black Pine bonsai tree is known by the scientific name of Pinus thunbergii. This beautiful plant is characterized by delicate needle-like green leaves that always grow together in pairs.

During springtime, the Japanese Black Pine will produce small reddish flowers. Later, it will also grow small brown cones. This hardy species can tolerate very strong winds and ocean spray. In Japan, the Japanese Black Pine has been one of the most popular plants to use in architecture.

If you are looking for a bonsai tree with striking appearance then the Japanese Black Pine may be the one for you. This is one of the most beautiful pine species of bonsai with characteristic delicate needle-like green leaves that grow in pairs.

The Japanese Black Pine looks lovely as it is but waits till you see its small reddish flowers which usually appear during springtime.

Native to Korea, Japan and north-eastern China, the Japanese Black Pine is quite striking in appearance. The irregularly shaped gray bark gradually transforms into black bark as it grows older.
Along the branches, the richly colored green leaves grow in needle-like shapes. Over time, the Japanese Black Pine can grow as tall as 100 feet. When kept in bonsai form, it becomes a miniature version of its larger brethren.

Each spring, the Japanese Black Pine produces red, egg-shaped female flowers. The male flowers produced are more of a reddish-yellow color and are mostly found on the branch tips. If users want to start new plants, they can use some of the tree’s seeds. Additionally, they can propagate it using cuttings or grafting techniques.
This sun-loving plant should always be placed in a mixture that contains 50/50 of pumice and akadama. Younger pines will like more pumice and older plants will generally prefer more akadama. No matter what, well-draining soils should be used that are between 5.5 and 6.5 on the pH scale.
In general, the Japanese Black Pine should be grown outside in full sun. This gorgeous plant can tolerate temperatures that reach above 100 degrees. Just remember—if the plant is kept in the sun all summer, it will transform into a greenish-yellow color.
This effect is perfectly normal, but if a user wants it to attain a different color they will have to put it in partial shade. Another thing to remember is to cover the roots. Although the plant can thrive in sunshine, a shallow pot combined with excessive sunshine can cause the roots to bake. Covering the pot with some kind of material can help the roots to stay protected.

It needs to be regularly watered, but the soil needs to dry out in between watering. This pine tree does not grow well in continuously moist soil. If users have to err with more or less water, choosing to water it a little less is better. It needs to be placed in a soil mixture and pot that promotes proper draining.

During the growing season, the Japanese Black Pine will need to receive extra attention. It will need to be watered and pruned more. Growers should use a sharp knife to do any pruning and put putty cut paste to stymie the wound. Pruning done in early fall often works better since sap bleeding is less of a problem during these months.

If individuals want to give it a more aged look they should bend the branches downward. To thin the leaves, gently pluck the needles that grow underneath and inside of the branches. Once this is done, the fissured bark will be exposed. The Japanese Black Pine can be grown in any bonsai style except broom.
This tree needs to be fertilized every two weeks during the growing season. Use a well-balanced liquid fertilizer for optimal results.
If it needs to be repotted, users should take advantage of a bonsai soil mix that drains quickly. Generally, this tree will not need to be repotted for at least two to five years. Growers can determine its repotting needs based off of the root growth and how old the tree is. If they do have to repot it, they should always be very careful not to remove too much of the tree’s roots.
These roots should be carefully rearranged so they can develop a strong surface root structure. After the tree has finished being repotted, it should be put in only partial sunlight instead of full sun. After three to four weeks have passed, it can be moved back into stronger sunlight.
If the grower wants to promote ramification, they can do this after the growing season is over by trimming the shoots. Winter is also a better time to wire the tree. During other seasons, the tree can suffer from sap leakage and be damaged.

Hardiness
Overall, the Japanese Black Pine is extremely hardy. Ideally, it should be grown in USDA Zones five through eight. During the winter, the bonsai tree will have to be protected from severe winter weather. It is susceptible to minors, root rot, blight, borers, rust and scales so growers should keep an eye out for any potential problems.
Growers should always take time and work slowly to train their tree. Successfully growing a Japanese Black Pine bonsai tree can take years. If growers prune too much at a time, it can cause too much stress for the tree to handle.
 
After the tree is pruned, it should always be put into partial shade for a couple of weeks to give it time to recover. If all of these steps are followed, users can enjoy having a beautifully, intricate bonsai plant at their disposal.