22 August 2014
Try Garrya Elliptica for Winter Interest
If you are looking for a wall shrub which will provide winter interest, then the silk tassel bush - Garrya elliptica - could be what you need. It's evergreen leaves and long, silvery catkins make it a striking sight. It can have a height and spread of 3-4m (10-12ft) when grown against a wall, but it also works as an informal hedge or as a shrub.
Garrya is dioecious, meaning that it has separate male and female plants, and although both male and female plants produce catkins, the male catkins are considered more attractive. Make sure you buy a named cultivar that is guaranteed male, though if you want to breed them you will need both male and female plants.
Garrya needs a sheltered site, as it easily suffers leaf scorch in windy or exposed sites, but works well as a wall shrub, where it benefits from extra shelter and warmth. It is shade tolerant, so is happy growing against a north – or east-facing wall, but is best not planted in the coldest parts of the UK or in frost pockets.
Garrya should be planted between autumn and spring, and prefers well-drained soil.
Your Garrya would appreciate an annual feed of 50-100g per sq m (1˝-3oz sq yd) of general-purpose fertiliser every late winter, though if you are growing one in a container it will need feeding from early spring until late summer. It would also benefit from mulching to suppress weeds, provide nutrients, improve soil conditions and conserve moisture. Shrubs are usually mulched in late winter, after any fertiliser application, but can be mulched any time between autumn and late spring provided the ground is damp.
Newly planted shrubs will need careful watering, but once established they usually need little water.
Where pruning is required, it should be carried out in early spring, as the catkins start to fade, but before new growth starts.
Garrya is well suited to being grown as a fan or an espalier against a wall, and should be treated as follows:-
Cut the plant back to one or two framework branches before planting. Tie these framework branches to bamboo canes, which are then attached in a fan shape to horizontally-placed wires on the wall or fence. Cut back any side shoots which grow out from the wall, and tie in well-placed new shoots to the framework, extending and filling in the fan framework. Use extra bamboo canes if necessary.
Where Garrya is grown as a hedge, it should be trimmed with secateurs or hand shears, not with a hedge trimmer, as a hedge trimmer will damage the leaves, causing ragged edges and scorching.
Free-standing shrubs are best left to grow un-pruned where there is space, but if pruning is required you should remove any crossing, rubbing or badly placed shoots, as well as any dead, diseased or damaged shoots. You can renovate your plants if required by cutting them back gradually over three to four years to a low framework of branches. Re-growth is vigorous and will need thinning out, selecting the strongest, best-placed shoots and removing the others.
Species plants can be raised from seed, but named cultivars are best propagated from semi-ripe cuttings taken in summer as they won't come true from seed.
Recommended cultivars are:-
G. elliptica ‘James Roof’ – male cultivar with dense clusters of silver catkins to 20cm (8in) or more. Height 4m (12ft).
G. × issaquahensis ‘Pat Ballard’ – male cultivar with upright, narrower shape; red-purple shoots and purple-tinged catkins to 20cm (8in) long. Height 4m (12ft).