Clethra Barbinervis Great Star White Alder

Clethra Barbinervis Great Star is an upright deciduous shrub with white fragrant flowers and good autumnal colour. It’s best grown in a shady border or a woodland garden.

Clethra Barbinervis or White Alder is native to Japan and China where it grows in open mountain forests. The variety Great Star has dark green leaves that appear in spring and turns multiple hues of orange and red in autumn before falling with the frosts.
In late summer the branches are tipped with small white flowers in long slender spikes that reach up to 15 centimetres long. These flowers are sweetly scented, attractive to pollinators, and a good way to feed the bees as summer blooms fade. On mature specimens peeling bark adds winter interest.
Japanese Clethra Great Star is a compact shrub that doesn’t take up too much room. It’s a good choice for pollinator-friendly shady borders.

Height And Spread of Clethra Barbinervis Great Star
White Alder Great Star reaches a height and spread of 2.5 metres over 10 years.

How Hardy Is Clethra Barbinervis Great Star
White Alder is a hardy shrub down to freezing temperatures if it’s grown in a sheltered spot with well-drained roots. It is rarely affected by pests.

How To Use Clethra Barbinervis Great Star
This large shrub provides colour and height to mixed borders in a shady spot. It is modern enough to suit town gardens and pretty enough to fit into cottage-style gardens too. It’s very versatile and provides year-round interest.
You can grow it in large well-watered and fed containers to brighten up a patio or balcony garden, but be sure to weigh it down so strong winds can’t topple it.

How To Care for Clethra Barbinervis Great Star
Grow Japanese Clethra Great Star in moist but well-drained acidic soil. It needs a dappled or partially shady spot with some shelter from the prevailing wind to flower well. If your soil is alkaline, bulk the planting hole with ericaceous compost and apply a thick layer of bracken or pine-based mulch in spring.
It doesn’t need pruning, but you can remove crossed or wayward branches in the dormant winter season. Lack of water is the number one killer of new trees, so give Japanese Clethra Great Star frequent water until you see new growth.
Apply a thick layer of acidic mulch to the roots in early spring to boost nutrients for the growing year and the best fragrant flower spikes.