How To Grow and Care for Pine Tree Bonsai

Pine trees, turned into pine tree bonsai, are popular for use in growing ornamental miniature plants in containers, but it is not a great option for beginners of the bonsai art. Bonsai is the ancient Japanese art form of growing artificially dwarfed trees in containers using cultivation techniques to mimic the shape and scale of full-sized trees. Since pines grow in many different shapes, sizes, and colors, pine bonsai can be shaped into nearly every known bonsai style successfully. If you are up for the challenge, several different species of pine, including many of the rocky mountain pine types, can be successfully used for bonsai cultivation.

Pine Bonsai Care

Pine bonsais are often considered to be a more advanced type of bonsai that are not ideal for beginners. They are one of the most difficult types of bonsai to understand, style, and prune since factors such as individual climate can greatly affect the requirements of the tree.

An important part of growing and shaping a healthy pine bonsai tree is proper wiring. Wiring is the practice of wrapping a wire around the branches of the bonsai tree to bend and reposition the branches to achieve the desired shape.

When practicing pine tree bonsai, it's important to know the type of pine you are growing. This way you can know how many growth flushes it has in a year (one or two), and when to do candling, or pruning of the tree's candles (the pine's upright buds at the branch tips during its growth flush) for correct wiring and shaping.

Wiring also promotes energy distribution throughout the tree. Avoid doing too much wiring at one time with pine bonsais to avoid damaging the tree. Wiring is best done in the winter months from late autumn to early spring.

Light

For best growth, pine bonsai trees require full sun for several hours each day. The more light the tree receives, the shorter and more compact the needles will be. Leggy, elongated needles on a pine bonsai are indicative of the tree needing more sunlight.

Soil

As with most bonsai species, pine bonsai require well-draining potting mediums. Commercially available bonsai soils/mixes are usually best. These contain a mixture of akadama (clay granulate mined in Japan), pumice, organic potting compost, and fine gravel/grit. Pine bonsais appreciate a soil pH between 5.5 and 6.5.

Water

Pine bonsai trees prefer to be kept consistently moist, but they cannot tolerate being waterlogged. As a general rule of thumb, water whenever the top inch or two of soil is dry.

Temperature and Humidity

Pine bonsai are not suitable for growing indoors and should be grown outside year-round. Pines are hardy, frost-tolerant trees, although, when planted in containers, they should be placed in a sheltered location so they are protected from the worst of the winter weather.

As with most bonsai, pine bonsai appreciate moisture and can benefit from regular misting if your climate is not naturally humid.

Fertilizer

Healthy pine bonsai trees require regular fertilization to achieve the best growth and appearance. Fertilize a pine bonsai from early spring to late autumn with an organic bonsai fertilizer for best results. Avoid nitrogen-rich fertilizers.

Types of Pine for Bonsai

The Pinus genus is extensive with over 100 different species. The following are some of the most popular pine trees for bonsai cultivation:

• Pinus thunbergii (Japanese black pine): This two-flush evergreen pine grows a thick, twisted central leader rather than a straight trunk, growing into a flat-topped tree with droopy branches.
• Pinus mugo (Mountain pine): Mugo pine is a single-flush pine that grows wider than taller, including 'Mops', a true dwarf perfect for bonsai.
• Pinus sylvestris (Scots pine): The long-needled single-flush pine is pyramidal in shape and boasts a very long life.
• Pinus parviflora (Japanese white pine): This popular and common single-flush pine has a spreading branch pattern, flat top, bluish foliage, and purplish-brown bark.
• Pinus aristata (Rocky Mountain bristlecone pine): This long-living single-flush pine, typically found in harsh landscapes, is slow to grow and drought-tolerant, but it is a popular bonsai choice.

Pruning

Proper pruning is essential to the aesthetic and health of a bonsai tree. It is necessary to begin shaping pine bonsai from an early age to establish a strong branch structure.

In general, pine tree species are apically dominant in terms of their growth habit—meaning that they grow vigorously at the top and outer reaches of the tree. A poorly pruned pine bonsai will become top-heavy at the expense of the lower branches, and it will also establish fuller growth around the outer edges of the branches—which is unsuitable for the aesthetic of bonsai.

A pine will have either one (single) or two flushes of annual growth, depending on its type. In the spring and summer, elongated candles of pine trees that experience two flushes of annual growth should be shortened and excess old needles should be plucked from any areas with dense growth. Reserve any heavy pruning of the main branches for the fall months to avoid excess sap loss in the spring and summer. the candles of one-flush pine trees should not be fully removed.

Propagating Pine Bonsai

Bonsai are grown from regular trees and can be propagated from cuttings, but be aware that the process can take quite a while, even years before you can start to see a resemblance of one of these miniature plants. Growing bonsai from seeds can be done but it is an even longer process. Here's how to propagate with cuttings:

• Take a cutting with disinfected pruning shears, about 2 to 3 inches long, from a regular pine tree of your choice. Cut it at a 45-degree angle.
• Plant the cutting about 1 inch deep in a pot prepared with bonsai potting soil and water.
• Put the cutting in a sunny location.
• Keep the soil moist and the roots should develop in approximately three weeks.
• Then the waiting begins to be able to prune and wire the cutting into the shape desired.

Potting and Repotting

Regular repotting is not a requirement for pine bonsai. Depending on the age of the tree, pine bonsai usually only requires repotting every two to five years. This will be to refresh the soil and root prune to prevent the tree from becoming root-bound.Repotting pine bonsai is best done in the early spring, just after the buds begin to swell.

When choosing a new pot for your bonsai tree, there are several things to take into consideration. According to the rules of bonsai, a pot's height and width should not be more than two-thirds of the tree, both for function (root restriction) and for aesthetics and design. Color is another important factor in choosing a bonsai pot, and the general rule is that the color of the pot should appear somewhere in the tree. The overall goal is to create harmony between the tree and its pot.

Whether you decide to follow the traditional rules of bonsai or not, bonsai trees can technically be grown in many different containers. Keep in mind that the pot should offer adequate drainage, and the size and depth of the pot relative to the tree are important in controlling its size.

Common Pests and Plant Diseases

Unfortunately, pine bonsai species are susceptible to a number of common pests and diseases. Keep an eye out for aphids, spider mites, scale, and caterpillars, along with common diseases such as root rot (usually due to overwatering or lack of proper drainage), as well as fungal diseases.

Common Problems With Pine Bonsai

Pine tree bonsai can be challenging to grow, and that's usually due to their growth flushes, which means it takes longer to style the specimen than it does a ficus tree, for example. Other than that, be on the lookout for other issues with pine bonsai:

Yellowing Needles

There are plenty of reasons for yellowing needles on a pine bonsai. In addition to old needles that naturally turn yellow, here's a host of other reasons:

• Newer needles that are yellow more towards the base than the tip may mean the plant is being overwatered, so it's best to let the tree dry out.
• It may mean the tree needs more fertilizer.
• Yellow bands on the needles may mean physical damage or the presence of a fungal disease.
• Yellowed needle tips could mean the bonsai tree is getting too much sunlight.
• The quality of the water could be poor with too many salts or the water's pH is too high preventing the pine tree from taking in nutrients.
• The soil is not draining well, which requires repotting.
• There could be an insect infestation.

Leggy Needles

Leggy, elongated needles on a pine bonsai are indicative of the tree needing more sunlight. Better light shortens needle length, which is preferred for a pine tree bonsai.

Dying Individual Branches

Branches may have been physically damaged resulting in a yellow portion of the tree, and there may not be an underlying reason for the problem. Or, some branches may not get enough light resulting in blackening or dying off. The final reason could be tree boring beetles or flathead borers causing havoc with your pine bonsai. If there is borer damage, the tree may not be worth saving. Prevent future infestations with wound paste after pruning.

From: thespruce