Grown for bright fruit, evergreen foliage (may be semievergreen in cold climates), versatility in the landscape, ease of culture. All grow fast and vigorously, varying in habit from upright to sprawling. All have glossy green, 1- to 4-in.- long, - to 1-in.-wide leaves that are generally oval or rounded at ends; all bear flowers and fruit on spurs along wood of last year's growth. Small, spring blooms are dull creamy white, carried in flattish clusters; they're effective thanks to their profusion. Nearly all species have needlelike thornsthus, the common name, firethorn.
The real glory of firethorns is in their thick clusters of pea-size, orange-red berries, which light up the garden for months. Selections with red, orange, or yellow berries are available; if color is important to you, buy plants when they are in fruit. Depending on selection, berries color up from late summer to mid-autumn; some types hang on until late winter, when they are cleared out by birds, storms, or decay. Dislodge old, withered or rotted berries with a jet of water or an old broom.
As shrubs and ground covers, firethorns look better and fruit more heavily if allowed to follow their natural growth habit. Prune only to check wayward branches. Plants can also be espaliered or sheared as hedges (though shearing comes at the expense of much fruit). Firethorns tolerate most soils but should not be overwatered. Two serious problems are fireblight (which can kill the plant) and scab (which causes defoliation and sooty-looking fruit); for best success, choose disease-resistant selections.
P. angustifolia 'Yukon Belle'. Zones US, MS, LS, CS; USDA 6-9. Selection of a Chinese native. To 810 ft. tall, 68 ft. wide. Bright orange berries. Quite cold hardy.
P. coccinea. SCARLET FIRETHORN. Zones US, MS, LS, CS; USDA 6-9 . From the eastern Mediterranean. Rounded growth to 810 ft. high (20 ft. trained against wall). Red-orange fruit. Best known for its cold-hardy selections, which include the following.
'Chadwickii'. Compact to 6 ft. high and spreading a few feet wider. Abundant orange-red berries.
'Red Cushion'. Spreading to 4 ft, high; 6 ft wide.
'Rutgers'. To 3 ft. high, 5 ft. wide, with orange berries. Good disease resistance.
P. crenatoserrata (P. fortuneana, P. yunnanensis). CHINESE FIRETHORN. Zones MS, LS, CS; USDA 7-9. From China. Vase-shaped plant to 15 ft. tall, 10 ft. wide. Limber branches make it a good choice for espalier. Orange to coral berries last through winter.
'Graberi'. More upright than the species, with huge clusters of dark red fruit.
P. hybrids. This category includes some of the most desirable rethorns. Plants vary in size, habit, and cold hardiness.
'Apache'. Zones US, MS, LS, CS; USDA 6-9. To 5 ft. high and 6 ft. wide. Large bright red berries last well into winter. Resistant to reblight and scab.
'Fiery Cascade'. Zones US, MS, LS, CS; USDA 6-9. To 8 ft. tall, 9 ft. wide; berries turn from orange to red. Good disease resistance.
'Gold Rush'. Zones MS, LS, CS; USDA 7-9. To 10 ft, high and wide. Orange-yellow fruit. Resistant to scab.
'Mohave'. MOHAVE PYRACANTHA. Zones US, MS, LS, CS; USDA 6-9. To 12 ft. tall and wide. Heavy producer of big orange-red fruit that colors in late summer and lasts well into winter. Resistant to reblight and scab.
'Navaho'. NAVAHO PYRACANTHA. Zones US, MS, LS, CS; USDA 6-9. To 6 ft. high, 8 ft. wide. Orange-red berries. Resistant to reblight and scab.
'Red Elf'. Zones MS, LS, CS; USDA 7-9. Densely branched plant to 2 ft. high and widegood in containers. Long-lasting bright red fruit.
'Ruby Mound'. Zones MS, LS, CS; USDA 7-9. Among the most graceful of ground cover rethorns. Long, arching, drooping branches make broad mounds 212 ft. high, spreading to about 10 ft. Bright red fruit.
'Silver Lining'. Zones MS, LS, CS; USDA 7-9. Grows to 3 ft. high and wide. Green leaves with white edges. In winter, leaves turn purple with pinkish-white edges. Few berries.
'Teton'. TETON PYRACANTHA. Zones US, MS, LS, CS; USDA 6-9. Very cold hardy. Columnar growth to 12 ft. tall, 4 ft. wide. Golden yellow fruit.
'Tiny Tim'. Zones US, MS, LS, CS; USDA 6-9. Compact, small-leafed plant to 3 ft. high. Few or no thorns. Red berries. Informal low hedge, barrier, tub plant.
P. koidzumii. FORMOSA FIRETHORN. Zones LS, CS; USDA 8-9. Unruly grower to 812 ft. tall and wide. Selections are better known than the species and include the following.
'Santa Cruz' ('Santa Cruz Prostrata'). Low-growing, spreading plant, branching from base. To 6 ft. tall but easily kept below 3 ft. by pinching out the occasional upright branch. Red fruit. Plant 45 ft. apart for ground or bank cover. Very resistant to scab.
'Victory'. Vigorous growth to 10 ft. tall, 8 ft. wide. Dark red berries color late in the year but hold on well. Resistant to scab.