Pyracantha, or firethorn, is a popular wall shrub grown chiefly for its fire-coloured berries, although itsare not unattractive. It is evergreen and hardy, so does not need the protection of a wall, but it does seem to go naturally with a wall, being slow growing and easy to train, and having dense vegetation which can be used to cloak an unsightly support. P. coccinea is the most popular species. It grows to a height and spread of 3.6 m (12 ft), and white in June and July are followed by bright red berries in the autumn ‘Lalandei’ is the most popular cultivar, and with its erect habit of growth it is more suitable for a wall or fence. It can go to 6 m (20 ft). Its are bigger than those of the species, and its berries more orange.
P. crenulata Rogersiana’, generally known as P. ‘Rogersiana’, grows to 3m (12 ft). Its large white flower dusters are borne in June, and are followed by orange berries. Among its cultivars is ‘Flava’, which has yellow berries. P. angustzfolia, up to 3m (loft), has the advantage that its orange berries seem to be disliked by birds, so they last all winter. Another cultivar is P. atalantioides, a vigorous grower with an erect stance which takes it to 5.5m (18 ft) in height, given the right conditions. P. ‘Mohave’ is an American hybrid with orange-red berries from mid-August onwards. Another very popular hybrid is the Dutch one, P. ‘Orange Glow’ which makes an excellent specimen plant, very vigorous and free-fruiting. Both these are said to have some resistance to scab.
General care: Pyracantha are happy with any soil, induding chalk, but not heavy clay. They will grow in shade or semi-shade, and dislike a sunny south-facing wall. Plant-grown specimens in March, in well and making sure that they do not dry out. Tie to wires or trellis as they grow up the wall. Trim back the current year’s growth in June.
Propagation: Pyracantha will grow readily fromharvested in the autumn, but if the is from hybrids the resulting plants are unlikely to grow true. It is safer to take semi-ripe of the current year’s growth in the summer, and strike in a 50-50 sand and peat mixture.
Pests and diseases: Birds take the berries, especially of P. coccinea. Try cotton strung between the shoots.should be sprayed with diazinon when seen. Pyracantha scab causes a brown coating on leaves and fruit. Spray fortnightly with captan. Fire-blight, a bacterial disease causing leaves to turn dark brown and wither, is on the increase. Cut away the shoots well beyond the infection and burn, and disinfect the secateurs. (Fireblight is a notifiable disease.)
The firethorns are often planted against walls and they can be trained in such places very effectively, but they are not climbers, they will make big bushes in the open and are perfectly hardy. They have clusters of white flowers in early summer followed by red, orange or yellow berries in autumn and winter and all are evergreen. They will grow in sun or shade, but flower and fruit best with plenty of light. They are not fussy about soil and do especially well on chalk and limestone. All can be pruned in spring or summer, the most convenient time for doing this usually being immediately after flowering when it can be seen where the berries are forming and care be taken not to cut them off.
Good kinds are Pyracantha atalantioides, scarlet berries; coccinea lalandei, orange-red berries; Orange Glow, similar to lalandei but more resistant to disease; rogersiana flava, yellow berries, and watereri, red berries.