Pyracantha is also called firethorn. The three most popular species, scarlet firethorn (Pyracantha coccinea), Formosa firethorn (P. koidzumii), and Roger’s firethorn (P. rogersiana), vary mostly in berry size and color.
Despite its fierce thorns, pyracantha is an important shrub in the South Carolina landscape.
This broadleaf, evergreen shrub grows to 10 to 15 feet and spreads 10 feet. All species have glossy green leaves, which are ½ to 1 inch wide and 1 to 4 inches long. All bear flowers and fruit on spurs along the wood of last year’s growth. Flowers appear in spring. They are small, white and have an unpleasant smell. The red berries are the main reason for the shrub’s popularity. They appear in thick clusters and are orange to red in color, depending on the species and variety. Most berries last until late winter.
Pyracantha grows very fast, sometimes more than 2 feet a year.
Pyracantha makes an excellent hedge. The shrub can also be used as a barrier or as cover for slopes in hot, dry areas. Pyracantha grows well in containers. It is not recommended for planting around the foundation of a single story building, because it grows too large, too fast.
Pyracantha prefers full sun to partial shade and well-drained soil. Planting in highly fertile soil will produce rampant growth, which makes the plant more susceptible to fire blight and decreases berry production.
It is best to plant pyracantha bushes in the fall. If berry color is important, buy the plants when they have fruit. Pyracantha resents transplanting. Once you plant it, leave it alone.
Even though pyracantha is resistant to heat and drought, it is a good practice to mulch around the shrub to reduce stress from dry weather.
Pruning can be done during almost any season, but winter or early spring pruning is recommended. If you wait until early spring when flowering occurs, you can selectively prune to leave some flowers so you will have berries in the fall. Flowers and berries are produced only on growth that is at least one year old. Always leave some of the growth made each year so that you will have flowers and berries.
Dislodge old withered or rotted berries with a broom at the end of winter.
Two serious problems on pyracantha are fire blight, a bacterial disease that can kill the plant, and scab, a fungal disease which causes defoliation and turns fruit a dark, sooty color.
To minimize problems, choose disease-resistant selections such as ‘Apache,’ ‘Fiery Cascade,’ ‘ Mohave,’ ‘Navaho,’ ‘Pueblo,’ ‘Rutgers,’ ‘Shawnee’ and ‘Teton. ‘
Insect pests include aphids, scales, spidermites and lace bugs. Some selections that are resistant to lacebug are ‘ Variegata’ and ‘Aurea.’
Hybrids of pyracanthas include some of the most desirable firethorns.
- ‘Apache’ grows to 5 feet high and 6 feet wide and has large, bright red berries that last well into winter. This selection is resistant to fire blight and scab.
- ‘Fiery Cascade’ grows to 8 feet tall and 9 feet wide, has orange berries that turn red during the winter and has good disease resistance.
- ‘Gnome’ is very cold hardy and grows to 6 feet high and 8 feet wide. The berries are orange. This selection is very susceptible to scab.
- ‘Lowboy’ is a spreading plant, which reaches a height of only 2 to 3 feet. The berries are orange, and this s election is also prone to scab.
- ‘Mohave’ grows to 12 feet tall and wide and has many, big orange-red berries, which last well into winter. This selection is resistant to fire blight and scab.
- ‘Teton’ is very cold hardy and grows to 12 feet high and 4 feet wide. The berries are golden yellow. This selection is also resistant to fire blight and scab.
- ‘Tiny Tim’ is a compact plant to 3 feet high with small leaves and few or no thorns. The berries are red.