Witch hazels are among the best winter-flowering shrubs, forming spreading plants given space, but can be grown in small gardens with suitable pruning
In time most Hamamelis make spreading shrubs up to 6m (20ft) in height and spread. As mature plants they are best displayed in situations where their attractive form can be appreciated. They are, however, slow growing and usually make little more than 3-4m (10-13ft) in 10 years, so it is quite possible to enjoy them for many years even in small gardens. Where space is more of a premium, they can be pruned annually to restrict growth. Most cultivars seem quite happy in full sun or partial shade, but in deep shade growth can be straggly and flowering sparse.
Pruning to restrict size
Where there are no restrictions on space, witch hazels need little pruning other than to remove dead or damaged growth. Where pruning is necessary, do it in early spring as the flowers fade but before the leaves open.
As with any shrub, remove congested, crossing growth or any weak or diseased shoots. To restrict an established plant but maintain the natural form, take back two or three longer branches to a well-placed side branch. This thinning of the longest growth reduces height and spread, but be careful not to remove too many branches. Pruning encourages the formation of flowering sideshoots.
Where shrubs are pruned harder to restrict their growth (see below) it is important to distinguish leaf buds with their longer, narrower shape from the fatter, more rounded flower buds.
Witch hazels can also be grown against fences and walls as fan-trained shrubs. Tie in the main shoots of a bushy plant to horizontally-placed wires. Leave the best-placed shoots to extend the framework uncut, cutting strong sideshoots to two growth buds after flowering each year.
Dealing with suckers
Most cultivars are propagated by grafting onto a rootstock of Hamamelis virginiana. This may produce suckers, but these are fairly easy to recognise as they hold onto their leaves longer in autumn. Follow such shoots down and carefully pull off at their point of origin on the rootstock.
To avoid problems, do not plant too deeply or cover the graft union. Annual feeding and mulching, with additional watering in dry spells, promotes strong growth and discourages suckering.
Tony Dickerson