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There are approximately 50 to 70 unique species within the cypress family. Together, these make up the juniper genus and are all coniferous trees or shrubs.
You can find Juniper Bonsai trees in many large stores such as Home Depot or Walmart. This ease of purchase makes them a very popular choice.
Also known as Green Mound Junipers or Juniperus Procumbens Nana, most Juniper Bonsai trees you find in stores are Japanese Garden Junipers.
There are other popular species in this family such as the Japanese Shimpaku (Juniperus Sargentii), the Chinese Juniper (Juniperus Chinensis, the Japanese Needle Juniper (Juniperus Rigida), and two central European species known as the Savin (Juniperus Sabina) and the Common JUniper (Juniperus Communis).
And we can not forget the three American species: The Rocky Mountain Juniper (Juniperus scopulorum), The California Juniper (Juniperus Californica), and the Sierra Juniper (Juniperus Occidentalis).
All of these plants have very similar care guidelines which we are going to discuss today. Each Juniper Bonsai tree is characterized by its longevity and sheer sturdiness. The whole species is very well suited for deadwood designs and also looks very good thanks to their exceptionally fine needle pads.
Because Juniper Bonsai grows very slowly, the maintenance required is very low. Today, we will guide you through the different types of Juniper Bonsai and the best ways to grow and care for them from your very own home.
But, before we find out how to care for these special trees, let’s discover the different Juniper species available so you know what you’re dealing with.
Juniper Bonsai Species
Junipers tend to have two types of foliage:
A scale juniper’s new growth appears needle-like. This is until they mature and the scale-like foliage begins to emerge.
Scale juniper’s new growth is also known as juvenile growth. This needle-like foliage can also result from heavy pruning, bending, or even overwatering the plant.
If this occurs, the scaly foliage can stay for several years until the regular scale-like foliage grows and fresh needle-like foliage falls.
This foliage can vary in colors from light greens to dark bluey-greens. On rare occasions, you can be met with dazzling silver or gold hues.
A juniper’s berry-like cones are either oval or completely round. Inside are round or edge seeds that can measure from ⅛-inch to 1-inch (0.3 cm to 2 cm) depending on the species.
For these seeds to ripen, it generally takes around one to two years. However, the cones are regularly eaten by birds who then spread the germinable seeds through their droppings so the plant grows in different areas and regions.
Junipers are certainly very good for jin and shari or deadwood. Below dying or broken branches, the tree grows veins that eventually dry out and die.
The result is deadwood which can be peeled, polished, and then bleached by different environmental conditions. This makes the wood extremely durable.
And when you consider the combination of its reddish-brown or yellow-brown bark, its green foliage, and silvery-white deadwood, the Juniper bonsai becomes a very attractive plant.
As we mentioned above, there are different species of Juniper bonsai. Considering the two types of Junipers (scale-like foliage and needle-like foliage), there are some popular juniper species with both.
For bonsai with scale-like foliage, the two most popular species are Chinese Juniper and the Japanese Shimpaku. In fact, the Japanese Shimpaku is a variety of the Chinese Juniper, originating in the picturesque mountains of Japan.
Both species have scale-like foliage with varying colors. These range from yellowish-green to blue-green and even silvery-green hues.
Another very popular juniper for bonsai is the Itoigawa Shimpaku. Its eloquent yet delicate emerald-green foliage is a hit with many homeowners around the world.
The Chinese Juniper has multiple varieties and many of these are actually very difficult to distinguish from each other. The good news is that the care guidelines are very similar for all of these junipers.
Hailing from Southern Europe, North Africa, and some regions of Asia, the Savin is another juniper with scale-like foliage. However, this scaly foliage tends to be finer and or, sometimes, more coarse with different shades depending on its origin. Don’t go consuming any of the Savin though as all parts of it are poisonous.
Then, there is the California Juniper. As the name suggests, this is native to California and sports bluish-gray scale-like foliage. When left in nature, it doesn’t grow very large. It will usually reach the size of a small tree or shrub.
Growing in Western North America, the Rocky Mountain Juniper can grow much taller than the California Juniper. Reaching the heights of tall trees, the Rocky Mountain species has scale-like leaves that are coarse with a dark green or bluish-green coloring.
The Sierra Juniper is another species of the juniper bonsai. This is a shrub or tree native to the western regions of the United States. Growing in mountainous terrains, it can happily live at altitudes of 2,500 to 10,000 feet (800 to 3,000 meters).
This juniper’s leaves are scale-like with dark green or grayish hues and it generally grows quite densely.
Some popular juniper species boast needle-like foliage. One of these is the Japanese Needle Juniper which has sharp, stinging, dark green needles with thin white lines across their entire length.
Another needle-like species is the Green Mound Juniper Bonsai. Hailing from Japan, this juniper’s needles are much shorter and more compact with bluish-green colors.
Looking at it, it appears more like some other scale-like foliage junipers. When wild, this plant grows as a ground covering shrub unless it is shaped.
Lastly, we have the Common Juniper, native to Europe, Asia, North America, and North Africa. Although its needles are smaller and more delicate than the Japanese Needle Juniper, they are very sharp.
When growing in nature, the Common Juniper grows columnar or in the form of a depressed shrub.
Care Guidelines for Juniper Bonsai
There are many factors you need to consider when taking care of a Juniper Bonsai. Below are some of the key care guidelines to see your plant live a long and healthy life.
Where to place
You should place the tree outside, all year round. Find a bright area that has a great deal of natural sunlight. Junipers cannot live indoors and this includes the colder winter months.
If temperatures drop below 15 degrees Fahrenheit (-10 degrees Celsius), the tree should be protected. You could drop the tree under a garden bench and then cover the bench with bubble wrap. This will provide enough protection against the harsh climate.
You could also take the trees out of their pots and plant them in your garden.
You may notice that your tree’s foliage color changes during frosty periods of the year into a purplish-brown hue.
This is no cause for alarm as it is part of the tree’s internal frost protection mechanism. When spring crops up again, the foliage will turn green once again.
You need to be careful how much you water your Juniper Bonsai. A juniper’s roots do not like soil wetness so do not overwater the plant. Before you water, you should ensure the soil is slightly dry.
You can also mist the tree frequently, especially once it has been re-potted.
You should only use normal organic fertilizer pellets. During the growing season, add these pellets every month or you can use a liquid fertilizer every week. For stronger growth, you can also apply some higher nitrogen levels during the springtime.
The foliage pads need all the help they can to develop properly. For effective development, the long shoots that stick out of the silhouette can be cut or pinched at their base during the growing season. You will need sharp scissors to do this. You should not trim the juniper as you would with a hedge.
If you remove the growing tips, the tree will become weaker and the cutting will force the needles to turn brown. If the foliage pads become very dense, you must thin them out with sharp scissors at their base.
Overall, the Juniper Bonsai is a strong tree. It can easily withstand aggressive pruning so don’t be afraid of tackling it with force. However, it is unable to bud again from bare tree parts. Therefore, you have to take utmost care that you leave some foliage on every branch which you want to keep alive.
When junipers are grown for Bonsai, they are usually thoroughly wired at a young age. Think of a Bonsai tree and you can probably picture strange, dramatic shapes coming from its branches and trunk.
These twisted shapes are very popular but they are actually similar to the natural shapes that you see grow in Japanese mountains.
Junipers are tough. They can be twisted aggressively and with force. However, when you use wire to move the branches, make sure you wrap the branches with raffia or tape for extra protection.
You must use caution when bending certain areas of deadwood as these tend to break easily. If the wood is quite large and old, it is possible to split the deadwood so it becomes more flexible to bend.
You should wire the foliage pads and fan them out after thinning. This is to let air and light in. If insufficient amounts of light and air are provided, the inner sections of the foliage pads will probably die and denser pads will also increase the chance of an infestation of various pests.
Every two years, a Juniper Bonsai tree should be repotted using a regular, basic draining soil mixture. If the tree is very old, it can be repotted after a longer interval. Just, do not prune the roots too aggressively as this could damage the whole tree.
Buying a Juniper Bonsai
You can usually find different juniper species of different sizes in most nurseries. This is the best place to generally find suitable raw material for Bonsai. If you’re looking for older Bonsais, you should look in gardens, cemeteries, or concrete pots. If an old grave needs to be cleared, you could ask for the Bonsai.
There are also specialized Bonsai traders who can provide young plants, Pre-Bonsai, and even pre-styled juniper trees as well as highly sought-after Bonsai coming in various shapes and styles.
The best method of propagation is to use seeds or cuttings. As long as you place the plant in a suitable area (as discussed above), then it should thrive and continue to grow into a strong, mature Bonsai.
Pests and Diseases
With proper maintenance, care, and being placed in an ideal location, junipers are usually very resistant to pests. You must ensure the foliage pads do not become too dense to avoid the risk of pests settling in.
During the winter months, junipers must be kept in a space with enough light. Even during this cold season, you should inspect the plant regularly for any pests.
They can be prone to infestations from spider mites, juniper aphids, juniper scale, juniper webworms, and juniper needle miners. You can tackle this problem with insecticide or miticide.
However, if you wish to get rid of the pests, once and for all, we suggest investigating why the tree was so prone to such an infestation in the first place.
As well as pests, fungal diseases can be a significant issue for junipers but different species of juniper have varying levels of susceptibility to rust fungus. A handful of junipers are thought to be resistant to fungal rust diseases.
In general, blue-green junipers are more resistant than junipers with yellow-green foliage. Moreover, Japanese junipers tend to get infested less regularly than others.
Rust fungus can permanently infest junipers. If your juniper has become infected, there is no way of curing it. This fungus can cause swelling in the tree that then erupts with brown gall-like parts on the plant.
During the colder months, particularly when it’s raining, these galls produce large, gelatin-like tendrils that are orange in color and full of spores. These spores infect the leaves of hawthorn/crabapples or pear trees.
Some signs of the fungus include orange spots on pear leaves and, during late summer, brownish markings grow quickly from the bottom sides of the plant’s leaves. These release spores that go on to infest juniper plants.
Pear trees are very rarely fatally affected. They are infected with a new spore every year or so and can even be treated and cured successfully with a fungicide. Unfortunately, infected junipers can not usually be treated.
The branches that have been infested tend to die while the fungus spreads and emerges on other parts of the tree. Even if you remove the branches with swellings and galls, there is little chance of the fungus not reappearing.
Nevertheless, some believe they can be saved. But we recommend burning a rust-infected juniper as soon as there are signs it has been infested with pests and diseases. You could also place it in your garbage rather than your compost heap for safe disposal.
The Benefits of Juniper Bonsai
There are some excellent benefits to owning a Juniper Bonsai. Some of these include:
- Juniper Bonsai are frost-tolerant and very hardy outdoor bonsai. They can be left outdoors during winter and survive quite cold climates.
- It is a perfect species for dramatic deadwood bonsai styling (Jin and Shari).
- When a Juniperus bonsai has been planted in a bonsai pot, it is usually very easy to care for.
- These trees can tolerate mid-summer sunny locations with very high temperatures. They can even withstand short periods of dry weather too.
- Juniper Bonsai live a very long time and are rarely affected by pests and diseases.
Juniper Bonsai is a great plant to own. Easy to grow and care for, both novice gardeners and experienced green fingers can enjoy the ownership of these unique bonsai.