Hello all bonsai devotees. How are you? My name is Suhendra. I want to tell you my experience on how to keep, treat and create black pine bonsai. Perhaps this experience is only suitable for tropical area and I hope those who plant black pine will also have different experience to share. I have tried to plant black pine since 5 years ago (around 1980) when I got the seed from a friend traveling abroad.

I have known and fallen in love with black pine bonsai, since I had learn about bonsai for two years from a foreign book on how to treat and create bonsai by practicing directly, so that I gradually master it. When I learned that book, I saw a picture of black pine and Cemara (Juniperes) bonsai that were so beautiful and robust. Even more so the black pine with its cracked bark so that it looked old, antique and elegant. According to Taiwanese bonsai grower, black pine could live in both winter and summer. In those seasons, its leaves are still green and thriving, so that we can call it evergreen tree. From books I have read, I’m sure that this tree could grow in tropical area. From that time, I had been determined to get that kind of tree and tried to plant and grow it in Indonesia.

In the mids of 1980 I and my elder went to Taiwan to attend an international exhibition of bonsai. While looking for special new trees to enrich the variety of bonsai in Indonesia, from Taiwan I brought home some kinds of bonsai that I’d been always seen on some foreign bonsai books that we couldn’t find in Indonesian market (before 1985). They are: Hokkian Tea (Carmona mycrophylla), Pyracanta (Pyracanta Grenulata), Ulmus (Ulmus Parfiflora), Karet Kimeng (Ficus Microcarpa). After buying those bonsai, one thing I shouldn’t forget to be my prime target of searching is Black Pine. Setting aside my pocket money for returning home, I spent the rest to buy various kinds of pine, starting from seeds, young trees, half-grown bonsai, and grown-bonsai.

Some Taiwanese bonsai grower told me that Black Pine (Pinus Thumbergii) grows best compared with any other kinds of pine they plant. There are three kinds of Black Pine:

1. Those with long leaves (which is generally spread out in the market).
2. Those with short leaves (Seu Sung).
3. Those with mini leaves (Zuen Sau Hei Sung).

The three Black Pines are the most preferred by Taiwanese bonsai grower to be dwarfed. Beside that, I have learned some techniques on how to plant and treat black pine that I want to share with you.

PROCESS BEFORE PLANTING

Coming home, I had all my trees washed because it’s forbidden to bring the soil from Taiwan. This is the regulation among countries to prevent the spread of plant pest. Then I opened the plastic cover of mos (soil substitute covering the root so it stays moisturized along the trip) one by one. After that all the roots that had been cleaned from mos was soaked with plant vitamin or organic fertilizer liquid for about one hour. Last thing to do was to keep the plant out of soaking liquid and planted it on the pot.

MEDIUM FOR PINE (Suitable for Casuarina=Juniperus too)

3 bg sand of 1-2 mm (do not use powder sand) +
1 bg loose soil (Do not use sticky soil such as clay, etc.) +
1 bg humus (or compost to substitute humus).

After being mixed well, it can be used to plant (you can see how to plant in a pot on article of Loa Variegata). I’ve got a little story about sands. In around 1990 in Indonesia there has been found a kind of pit sand (pasir gunung) from perimeter of Malang, so that it is called pasir Malang (Malang pit sand). This kind of sand was found by hobbyist and raw-material (bakalan) bonsai hunter in the nature. The specialty of this sand is clean and has no powder or waste. We may say that it’s been free from pests and germs that are usually found on soil or pit sand. So there’s no need to have it washed it anymore and it has pores to keep water and air. There are several kinds of plant that are better being planted on this sand rather than any other media, i.e. Santigi (Phempis Acidula), Cemara Udang (Casuarina Equisetifolia), Black Pine, Cemara, etc. Naturally Malang pit sand is beneficial for bonsai hobbyists and some devotees of ornamental plants such as cactus, adenium, sansivera, etc. Then I use this pit sand as composite for media to plant Black Pine and other bonsai.

PROCESS AFTER BEING PLANTED

After black pine is being planted in a pot, the trunk always has to be tied tightly into the pot so that the tree is more stable. It’s because any repotting tree is in critical period. Its root hasn’t been converged with its new media so that it hasn’t been normally functioned. Moreover when we cut some of the roots and new roots grow, the latter is still easily snapped off if it is shaken, and the tree will be possibly died. After being tied, put it in the shade then water it perfectly (until the water comes out of the pot bottom hole). Let it be there for about two, but please not to let it be too wet or too dry. We’d better to keep it a little bit dry than to keep it too much wet, in order to prevent its root from getting rotten. This will be different from what we should do to growing black pine (see the description below on watering). After two weeks the trees will look healthy and strong with its green leaves. Now it’s time for the tree to have sun bath gradually. Then wait until new bud comes up, which is a sign that its new root has grown and the tree is ready to have a full sun bath.

There are some bonsai hobbyist who don’t know the media and the planting process, or don’t have much patience in planting and treating black pine (which is different from maintaining ficus or any other kind of bonsai). Doing treatment improperly will lead to the death of black pine. When this happens, they will easily say that black pine could not be planted in Indonesia or will be dead if it’s being re-potted. The worst is when there are bonsai hobbyists and sellers who has just seen black pine picture on bonsai books tell the same things. This makes bonsai newbies or collectors being defrauded and don’t want to treat black pine.

TREATING GROWN BLACK PINE BONSAI

The pruning (cutting the leaves), can be done when we see the old leaves has been grown yellow or looked a little bit dull. We can do it in two ways: shearing or pulling out. The best way is the second one, that is gradually pull out the old leaves. To prevent pulling out the whole group of leaves, use your left hand to hold the lower end of the leaves group, and use your right hand to pull out the old leaves one by one, and leave the young ones. If you prefer the first way, shear the old leaves at about 1 cm higher from the leaf stalk. This is to provoke the new bud from the rest of those old leaves. Unfortunately, shearing will leave brown traces, and these unsightly traces will stay there for months before they disappeared.

To keep the twigs and the leaves short and dense (to avoid disfigured or to keep the good shape), do the following:

1. Gradually pull out the old leaves every year.

2. Cut the twigs, small twigs, and new buds once every two or three years. This is to keep the shape from being undesirable. Two or three new buds usually come up once a year naturally. Cut off the very thriving (big) bud and the very weak (small) bud by shearing from the lowest part. Leave the moderate growing buds until they release their new leaves. Then cut it at the length we intend to. Two weeks later, there will come up the second bud from the trace of cutting. If it is needed, do the same to the second bud, so that we will get the third bud. The second and the third buds will create the short twigs and leaves. This theory is he same with bonsai tree that will have big leaves in the country but after making it bonsai planted on the pot by cutting its leaves several times, the leaves become small such as Sancang (Phemna Microphylla), Beringin Karet (Ficus Ratusa), etc.

3. When the leaves of the new bud have grown, do not cut off too many twigs when the leaves of the new buds has blossomed because in this phase, the trace of cutting will release much turpentine (sap) that will possibly kill the tree. The best time to shape and shear the twigs is when we start to see its old leaves (looks yellow and dull). This shows that this tree is stop growing temporarily and is saving energy before releasing its new buds. It’s the safest time to prune black pine by pulling out or shearing, and cutting the twigs too, because it’s the strongest period of the tree.

THE WAY OF REPOTTING / CHANGING THE SOIL OF BLACK PINE BONSAI

The process of repotting bonsai to be black pine can be done once in three or four years, because black pine’s root grows slowly. Do not repot before two years because its roots haven’t been old enough. If we repot after 4 years, the roots will be too dense in the pot, and this will retard its growth and fertilization.

Please repot this way. After pulling bonsai out of the pot, we may see the lump of root that has been converged with the soil. Throw 1/3 part around the lump by scraping the soil and shearing the roots that is too long. Then put it again into the pot with the medium described above, by scraping, so the tips of the old roots can directly penetrate into and converged with new medium. This will guarantee its life after repotting. Don’t even repot by cutting or sowing the lump of soil and root flat as if we’re slicing the cake and then plant it again. This way make the old root lump covered by the new medium, causing an undistributed heat in the lump and will finally make the root rotten.

According to my experience in planting black pine, we shouldn’t do pruning while repotting. Once my gardener didn’t follow my instructions. When I went out of town and didn’t supervise him, he was repotting and pruning at the same time. This caused some half-grown black pine trees died.

In Indonesia which has two seasons, the best time to repot black pine is between the end of dry season and the beginning of rainy season (around the beginning of September), but pay attention to black pine condition too. Repotting should be conducted when new bud has just come up before the leaves blossom. When the leaves have blossom, then the tree will be weak and the risk of repotting will be bigger.

Well, that’s my experience on treating black pine bonsai. Hope it’ll be useful for those who want to treat or collect black pine bonsai.