The firethorn is not only a really useful plant in the landscape but also a reliable source of color to brighten up gardens in early winter. The only downside is the plant’s sharp spines, but these can also be used to the gardener’s advantage. Read on to learn how to care for the firethorn, and if it is the right shrub for you and your garden.
What Is A Firethorn
Firethorn, Scarlet firethorn, or Pyracantha as it is often known is a medium to large evergreen to deciduous shrub from the Rosaceae family. The plant’s generic name is actually derived from two words, which literally mean fire-thorn.
This plant is reliably evergreen in mild climates, but semi-evergreen to deciduous in areas with colder winters. These plants are very similar in appearance to Cotoneaster but are easily identified by their sharp thorns.
The firethorn has a firm, semi-woody arching form and grows up to 18ft (5.5m) tall and equally wide. It is native to Western Asia, as well as the southern parts of Europe. There it is found in woodland, rocky areas, riverbanks, and the edges of grasslands (1).
Firethorn bushes have dark green, glossy leaves up to 1.5 inches (38mm) long. They are simple and alternately arranged, with serrate margins. The stems of this plant are a rich glossy brown color when young and the plants are armed with needle-sharp spines to nearly an inch (25mm) long.
Firethorns are showy when in bloom in the spring to early summer, producing masses of small white flowers in corymbs that measure 2-3 inches (5-7.5cm) long. Each flower measures about ⅓ inches (8mm) across.
If there is any downside to this bright floral display, it is the pretty unpleasant fragrance these flowers are known to have. Fortunately, perhaps, the flowering period is pretty short in this species.
The Pyracantha bush is most celebrated for the incredible amount of fruits (pomes) it produces each year. This display can last right into the winter adding valuable color in the cold months. These small round pomes vary in color from yellow through bright red and measure about ¼ inches (6mm) in diameter.
Each pome contains many small, dark seeds. The fruits are said to be edible, but the seeds are mildly poisonous. Considering the size of the fruits and the amount of effort it takes to remove the seeds, it is probably not worth the time unless you wish to make a sauce or jelly.
How To Grow A Firethorn
Firethorn is a fast-growing plant that can grow over 2 feet (0.6m) in a single growing- season. They can be grown from seeds, collected in the winter, or from cuttings. Take semi-ripe or greenwood cuttings in summer to early fall. Cuttings of around 3 inches (7.5cm) in length usually root well, with results taking just 4 to 6 weeks (2).
Pyracantha shrubs grow best in dry to medium moisture garden soils with a mildly acidic to neutral pH. They will do best in well-drained, fertile substrates, but they do tolerate clay soils.
These plants have moderate water needs. Supplemental watering is usually only necessary in hot, dry periods or climates. Young or newly planted specimens will also need regular water until established and growing well. Do not overwater, however, as this can cause root rot.
Applying a layer of organic mulch over the soil around the root zone will help to keep the soil moist and suppress competition from unwanted weeds. Just be sure to leave the area around the plant’s crown free of mulch as keeping this area wet can result in crown rot.
Position this shrub in full sun if you want to bring out the best colors and display. They will grow in partial shade if that is the only space you have available though. USDA hardiness zones 6-9 provide the perfect climate for growing firethorn plants and they are fairly salt tolerant.
Firethorn Care and Maintenance
Firethorn shrubs are very tolerant of shearing and pruning and can be made into a very neat formal hedge. These plants can be pruned at any time of the year, but if you want to avoid shearing off the berries, prune these plants in the early spring before they flower.
One downside to this plant is its sharp spines. This can make working with firethorns pretty tricky, and rather painful if you are not prepared. The thorns can even cause a nasty reaction in some people, so wear heavy clothes and gloves when pruning or working on this plant and take your time.
Fertilizing is not usually necessary in good to average garden soil. An application of a balanced fertilizer like 8-8-8, worked into the soil around the root zone can certainly improve plant growth and vigor, however. Avoid fertilizing after Spring though because new growth can obscure the colorful fruits.
Firethorns, like many plants from the Rosaceae family, can be quite susceptible to a number of common pests and diseases. These include the hawthorn lace bug, aphids, scale, root-rot, fireblight, and leaf blight.
Pests that are not removed by strong watering can be treated with neem oil. Some forms, like ‘Golden Charmer’, can be more disease-resistant than others.
Firethorn bush can be a very useful plant if you employ its defenses to your advantage. The thorns of this plant make it pretty much impenetrable, which is great for creating a security hedge to keep people or animals out of the yard.
Its tolerance for trimming and shearing means this species can be kept as a formal hedge or even used for topiary. It can be trained or espaliered against a wall and is more than showy enough to make a good specimen or accent plant.
Remember the thorns when choosing a position though, because pathways, doorways, and high traffic areas should be avoided. This plant’s dense and thorny nature works in its favor when planted as a security hedge. Alternatively, you can simply allow this plant to naturalize as a large, tall, and colorful groundcover for bare slopes.
Firethorn berries are edible but nothing to rave about. The flesh is described as similar to an apple’s, but rather powdery in texture. The seeds are mildly poisonous, resulting in the release of hydrogen cyanide in the body.
The berries are an important fall and early winter food source for fruit-eating birds. The thorny branches also create an excellent protected nesting site for birds. Bees and other pollinators visit the flowers of this plant. Fortunately, the firethorn is generally deer resistant.
If you’re looking for a large, showy evergreen shrub for zones 6-9, the firethorn could make a great choice. The long-lasting color these plants provide, often well into the winter months can really brighten up the landscape. The most important thing to consider before planting this species is its sharp thorns, however.
*image by ivusakzkrabice/depositphotos
- Vélez-Gavilán J. Pyracantha coccinea (scarlet firethorn). Invasive Species Compendium.
- Plant Propagation: The Fully Illustrated Plant-By-Plant Manual Of Practical Techniques.