Dwarf Pyracantha Bonsai Care Guide
Commonly known as Firethorn, this species of evergreen is native to southeastern Europe and east to southeastern Asia. The shrub may grow to 20 feet tall in its native habitat. Cultivars commonly used for bonsai include Pyracantha angustifolia and Pyracantha coccinea. This species bears a resemblance to its relative, the Cotoneaster.
Called Firethorn for its flame-colored berries – yellow, orange, or red depending upon the cultivar, as well as for its one inch thorns which grow along all branches. The dark green leaves are ovate and in some varieties are toothed.
In P. angustifolia the leaves have gray fuzz on their undersides and the berries are yellow to orange. P. coccinea has toothed leaves with scarlet red berries. The flowers are usually white and bloom in summer, with the berries starting out green and turning color in the fall.
While these are generally considered hardy plants, certain cultivars should not be exposed to temperatures below 40 degrees and may be kept inside during the winter. If kept indoors Pyracantha should still be kept cool, however, and if outdoors should be given protection from freezing winds. This bonsai should be placed in full sunlight, with some protection provided during the hottest midday summer sun.
Firethorn should never be allowed to dry out completely, and should be planted in very well-draining soil. Water more frequently during the growing season, as the plant will need plenty of water to produce its flowers and berries. Add water until it starts to drip out of the drainage holes. During winter it will not require as much water, but still check the moisture level about once a week to ensure the soil is not drying out too much.
Use a high nitrogen fertilizer from spring through early summer, then switch to a lower nitrogen mix to encourage production of flowers and fruit. DallasBonsai.com carries a full line of bonsai fertilizers as well as the Dwarf Pyracantha bonsai.
Popular Styles – informal upright, cascade, single or double trunk, group plantings.
Firethorn is tolerant to aggressive pruning. In early summer new growth may be removed down to a couple of leaves. In the process of shaping your bonsai, some flowers and berries will be lost – do not worry about this in the first few years, as the trimming and shaping will ultimately result in even denser blossoming. In the late fall trim new growth down, leaving only two or three nodes. Buds form at the tips of shorter mature branches so this will tighten the shape up and keep energy conserved to the areas where you want blooms.
Even though the thorns can be difficult to work around, do not remove them as new branches – hence new flowers and berries – will grow from them. Remove old, dried up wood yearly. Some bonsai enthusiasts choose to remove all buds every other year as this prevents flowering, thus all the plant's resources are directed to development of the trunk and branches.
Pyracantha can be wired, just be sure to wrap new branches early enough, as they become stiffer and more difficult to shape as they age. By the same token, use caution with younger shoots as they can be somewhat fragile up to two years old. These new shoots will respond well to movement, whereas the harder branches can take a long time to adjust to repositioning.
Firethorn can be grown from seed in the fall. Remove the seeds from the berries and soak overnight before planting outside. Cuttings take easily, and should be rooted in the summer.
This should be done at most every other year, possibly every three. Firethorn does not like to be repotted yearly, and the root system should be disturbed as little as possible. When potting and repotting, a well-draining mixture should be used – 60/40 inorganic to organic works well. You may use a completely inorganic mix but the top layer should be plant-based fertilizer, as this bonsai will need some organic material in order to produce its signature fruits and blooms.
Insects/Pests & Diseases:
Dwarf Pyracantha is vulnerable to a variety of insects. One of the most common on these bonsai is the aphid. Aphids can often be rinsed off the plant with a gentle jet of water. If this does not completely eradicate the infestation you may need to use an insecticidal soap. Alternatively, predatory bugs have been known to control aphids on bonsai – these include ladybugs and aphid midges. Firethorn may also fall prey to scale, spider mites, leaf miners, or caterpillars. Application of insecticide or, in the case of scale and caterpillars removing the insects manually, can be effective for these pests.
One of the biggest threats to Pyracantha bonsai is fire blight, a fungus which is spread by leafhoppers. The major problem with fire blight is that once your bonsai has the disease, it can virtually never be cured. Prevention is the best cure for this problem – always wash your hands before and after handling your bonsai, try not to expose it to other Firethorn trees, and keep a very close eye out for insects, removing them as soon as you spot them.