The pine or genus pinus has well over 100 species, most of which are responsive to bonsai art. The most popular species used is pinus thunbergii, commonly known as the Japanese black pine. Its historical home is throughout coastal regions of Asia. Masters of bonsai art revere this glorious pine and deem it challenging to grow due to its prolonged development and long, finger-like needles. It has various names in Asia; gomsol in Korean, hēisōng in Chinese, and kuromatsu in Japanese.
The beautiful pine leaves grow together in pairs. During the spring months, the Japanese black pine bonsai will produce small reddish flowers. It’s a hardy bonsai that can tolerate battering winds and salty ocean spray. It can also grow well in nutrient-deficient soil.
The tree, because of its hardy nature, is often used in architecturally designed or formal gardens. The trunk and branches boast spectacularly irregular shaped grey-hued bark; as it ages, it turns black, hence its eponymous name. The contrast of the black wood and the soft green-blue leaves makes it visually pleasing. In the wild, the Japanese black pine can grow in excess of 30 metres.
There are other popular pines used in bonsai, and the mountain pine retains its colour no matter the circumstances or how inclement the weather; it’s known for its spectacular purple blooms during the spring. In addition, the Scots pine is malleable and is easy to wire. Finally, the Japanese white pine is sought after by enthusiasts for its unusual and unique white-green needles.
During the spring, your pine bonsai will be covered in soft upright buds at the branch tips. These are known as candles and will grow in little clusters. The secondary candles protectively surround the largest and most prominent candle.
It’s possible to identify your pine bonsai by understanding their growth flushes. For example, the two well-known Asian species that produce two flushes of growth each year are the Japanese black and Japanese red pine. The coast loving Japanese black pine has hardened long, dark needles that grow as twins in clusters of two. In contrast, the red pine is more delicate and has softer, finer paired needles and looks more similar to the Scots pine; it likes to grow on hillsides away from the salty air.
Pines with only one flush of growth are used to much harsher conditions and will only have short growth periods. The Japanese white pine is a prime example of this mountain-dwelling tree. Its feminine, soft green needles grow in clusters of five. Enthusiasts regularly graft the white pine onto a black pine root system to promote stable growth. Dwarf cultivars of the white pine include kokonoe, myojo and zuisho species.
Scots pines grow from the UK, all over Europe and into the colder climes of Siberia. Its thin pairs of needles can be slightly twisted, and the bark is a deep red colour. In the same region, you’ll find the mountain pine, which is native only to European mountains and grows on rock layers as a shrub. Its short stature boasts chestnut brown wood, and its dark green needles are short and robust. The ponderosa pine is native to western North America and the Rocky Mountains. Its needles grow in clusters of three, and its pretty bark can be in hues of yellow, orange and even pink. Finally, the bristlecone pine is native to New Mexico and Colorado.
Care Guidelines For Pine Bonsai
Ideal Placement
Your Japanese black or red pine enjoy the full sun throughout the year. The bright sunshine helps to limit the needle length and develop the first and second flushes of growth. If the tree does not get enough sunlight, the needles will continue to grow. Although these pines are hardy, you’ll still need to protect them from cold winter weather and frosty snaps.
Water Requirements
Bonsai pines do not like to be overwatered or sit in a soggy pot, and you must ensure the drainage is adequate. Too much water can make the needles grow too long, mainly through the second flush of growth. The pines do not tolerate drought; take care to make sure that the soil does not become completely dry. Your plant will benefit from regular misting.
Soil And Fertilizing
In order to maintain a healthy pine bonsai, you should fertilise the tree from early spring to late autumn with a slow-release solid organic fertiliser. Give your bonsai time to rest in its dormant winter months. Avoid nitrogen-rich fertilisers.
Pruning Times
Pruning a pine bonsai requires patience and nimble fingers; as an enthusiast, you must resist removing too much growth and foliage. Pine bonsai are apically dominant, which means that vertical growth supersedes lateral growth in the tree. Your pine will grow at the top and outer reaches of the branches; you need to consider this carefully when pruning.
You’ll find it necessary to begin shaping your pine bonsai at a young age so that you can establish an excellent strong branch structure. Poorly pruned trees can become top-heavy and establish fuller growth on the outer edges of the branches. In the spring and summer months, you can carefully prune old needles and elongated candles. Reserve heavier pruning until the autumn so that you don’t lose sap from the tree. You can seal all pruning wounds with petroleum jelly.
Repotting Times
An average repotting programme should be somewhere between two and five years. However, it is the extent of the root development that dictates when. You should repot your pine in the spring, as the growing season begins and should be potted into free-draining soil. You should carefully wash and gently prune the roots to prevent the tree from becoming root-bound. Ensure that you retain some of the old soil because it contains nutritious mycorrhiza fungi that help maintain a healthy plant.
There are several rules for successfully growing a bonsai. When choosing a pot, its height and width should not be more than two-thirds of the size of the tree; this will not only control its size but provide balance and form. Interestingly, it is also recommended that the colour of the pot should appear somewhere in the tree to increase its overall aesthetic appeal. The goal is to create harmony for the tree.
Propagation Management
If you want to propagate your pine bonsai, you can choose from several methods; the first is from seed, the second from a heal cutting and finally, for the more experienced bonsai enthusiasts, by a technique called air layering.
For a cutting, it’s best to do it early to mid-autumn; your bonsai wood will be hardening, and the tree will be looking forward to some rest in the dormant period in the winter. Ideally, your cutting should still be reasonably green but also have some darker woody looking areas. You will make a tiny cut where the stem meets the main branch. As you pull it away, it will leave a small diamond-shaped scar.
When preparing your cutting pot, use relatively fine volcanic sand (pumice) and make sure that it is level and compact enough to support your cutting. Before planting, dip the wound end of the cutting into a rooting hormone which will stimulate root growth. Use a dibble stick to make a hole so that you can insert the cutting without dislodging any of the rooting hormones.
Compact the sand to ensure the cutting is firm. Keep the pine bonsai cuttings nice and damp either by regular misting and watering or covering with a ‘greenhouse’ cover that will keep in the moisture. You should have healthy roots within a couple of months to start your bonsai training.
Potential Pests and diseases
Pine bonsai can be affected by aphids, spider mites, scale, caterpillars, root rot and occasionally fungal diseases. It’s essential to action treatment as soon as you see the first sign of disease. If you don’t want to use a regular insecticide formula, you can try neem oil, a centuries-old solution ideal for treating houseplants and bonsai alike. The wash-off also protects roots from fungal problems. All in all, pine bonsai tend to be healthy if they are well cared for and in a sunny location.
Wiring Your Bonsai
Your pine bonsai will respond well to wiring and should be carried out with care, little and often. The ideal time for wiring is just after you have pruned the tree through to mid-summer.
Pine bonsai trees, whilst beautiful, are notoriously challenging and are definitely not for the inexperienced novice. The trees are very taxing, and you should gain experience with easier trees before nurturing and training a pine bonsai tree.
Included in the one flush category are the white, Scots, ponderosa and mountain pine bonsai. You need to treat them differently.
Ideal Placement
The one flush pines also thrive in full sunshine. The sun supports healthy growth and helps inhibit needle growth. If the tree does not get enough sunlight, the needles will continue to grow. Although these pines are hardy, you’ll still need to protect them from cold winter weather and frosty snaps.
Water Requirements
Your pine bonsai does not like to be overwatered or have permanent soil moisture; it, therefore, requires regular attention and good drainage. The pines do not tolerate drought; take care to make sure that the soil does not become completely dry. Your plant will benefit from regular misting. Excess water during the development of the shoots will encourage needle growth.
Soil And Fertilising
So that you can maintain a healthy pine bonsai, you should fertilise the tree from early spring to late autumn with a slow-release solid organic fertiliser. Give your bonsai time to rest in its dormant winter months and try to avoid nitrogen-rich fertilisers.
Pruning Times
The spring should see you pruning the candles, the tender upright bunches of shoots that grow from the end of each branch. Typically there is one central candle surrounded by several shorter ones. The candles should be short and evenly cut throughout the spring and summer, and in the autumn, cut away all of the candles apart from two. Also, in the autumn, before the dormant period, carefully pluck excess needles to balance the appearance and growth of the tree
Repotting Times
An average repotting programme should be somewhere between two and five years. However, it is the extent of the root development that dictates when. You should repot your pine in the spring, just as the buds begin to grow. Carefully wash and gently prune the roots to prevent the tree from becoming root-bound and pot the bonsai into free-draining soil. You can also repot your bonsai at the end of the summer, be sure to allow enough time for the bonsai to start growing new roots before the winter.
Propagation Management
If you want to propagate your pine bonsai, you can choose from several methods; the first is from seed, the second from a heal cutting and finally, for the more experienced bonsai enthusiasts, by a technique called air layering.
Potential Pests And Diseases
Pine bonsai can be affected by aphids, spider mites, scale, caterpillars, root rot and occasionally fungal diseases. It’s essential to action treatment as soon as you see the first sign of disease. If you don’t want to use a regular insecticide formula, you can try neem oil, a centuries-old solution ideal for treating houseplants and bonsai alike. The wash-off also protects roots from fungal problems. All in all, pine bonsai tend to be healthy if they are well cared for and in a sunny location.
Wiring Your Bonsai
Your pine bonsai will respond well to wiring and should be carried out with care, little and often. The ideal time for wiring is just after you have pruned the tree through to mid-summer.
Pine bonsai trees, whilst beautiful, are notoriously challenging and are definitely not for the inexperienced novice. The trees are very difficult, and you should gain experience with easier trees before nurturing and training a pine bonsai tree.
Frequently Asked Questions
Q. Why Is My Pine Losing Leaves?
A. A pine tree should not lose its leaves. If it is shedding its leaves, you are likely watering your tree too often. By not offering sufficient drainage, your bonsai can experience root rot. You may also be watering it too little, and a pine bonsai doesn’t react well to drought conditions. You may be over or under fertilizing your bonsai, which will also cause the tree to weaken and shed leaves.
Q. Why Is My Pine Bonsai Turning Brown?
A. There are a couple of reasons why your bonsai might be turning brown. The most common will be that you are over or underwatering your pine. Pay attention to the browning leaves. If the leaves appear to be soggy and brown, that is a prime indicator that you are overwatering the tree; however, if the leaves look dried and wilted, you have likely subjected your pine to drought. Hopefully, you will not have caused irreparable damage. You can improve the tree’s health by improving your watering techniques, examining the root ball and repotting where necessary.
Q. Which Pine Species Is Best?
A. Pine bonsai, whilst typically challenging to grow and maintain, are hardy and trainable trees. The pine can be trained into traditional and contemporary styles. There are over 100 species to choose from and characterised by their blue-green needles that appear in pairs or bundles of up to five. The bark can come in various colours, from yellow and pink through to the deepest black. The favoured species include the Japanese black, Japanese white, mountain and Scots pines.
Q. How Often Should I Water My Pine Bonsai?
A. This is a million-dollar question and an art. To gauge your bonsai’s water needs, you’ll need to feel the soil once or twice a day. When the soil is barely moist but not drought dry, you can completely submerge the entire pot in a bucket of water for about one minute. Remove the pot and let the excess water drain away. You can also flood the pot, ensuring that you water the entire surface of the soil.
If you have access to rainwater, use this; it doesn’t contain any intentionally added chemicals that could harm your tree. Your bonsai will also require some humidity, so either use your layered humidity tray or mist the leaves regularly.
Q. When Should I Work On My Pine Bonsai?
A. You can work on your bonsai little and often. It’s best to prune and repot during the spring so that the bonsai can benefit from complete regrowth and repair itself from any accidental damage. It would be best if you wired the pine during the late autumn or early winter months. The cambium layer of your tree is a green layer that lies just below the bark.
During the spring and summer, the cambium cells work tirelessly to divide and create new phloem and xylem cells constantly. During the winter, the process halts. This process is what creates a tree ring. There are two schools of thought about wiring. Some enthusiasts only recommend wiring during the summer months to repair any damage quickly during the growing process.