Pyracantha flowers mainly on shoots produced the previous year. So when pruning try to retain as much two-year-old wood as possible.
Wear thick gloves when pruning; firethorn, as the common name of Pyracantha suggests, bears long and very sharp thorns.
Prune out shoots badly affected by Pyracantha scab. These are easy to spot as the leaves and often the berries too will be covered in unsightly black scabs.
Pyracantha usually responds reliably to very heavy pruning when overgrown plants need to be renovated.
Free-standing shrubs merely need unwanted, damaged or diseased shoots removed.
Pyracantha can be trained against a wall. See our advice on pruning climbers and wall shrubs on first planting for more information on how to establish a wall-trained plant.
Pyracantha can also be trained as an espalier. See our advice in espalier training trees for more on this technique.
In general, prune to make the berries more visible and to keep the plants in shape. Shorten all sideshoots that arise from the main framework branches in late summer, stopping just short of the clusters of berries (usually about two to three leaves from the base of the side shoot).
If you need to extend the plants, tie new leafy shoots into wires or trellis. While the shoots are still flexible they can be trained to frame doors or windows.
Trim Pyracantha hedges two or three times between spring and the end of summer. Aim to retain as many berries as possible but some will no doubt be lost as you strive to keep the outline.