Clethra barbinervis seed (Japanese Summersweet)


An uncommon rounded flowering shrub with highly fragrant flowers loved by bees and butterflies.  Put it near a shaded moist pathway and you will love it too.

2 in stock

SKU: clethra-barb Categories: , , Tag:


Also known as Japanese Pepper Bush,  this gorgeous shrub received the Award of Garden Merit of the Royal Horticultural Society and for good reasons.  Sweetly fragrant 15cm long racemes of small white flowers clothe the new twig tips in mid-late summer, its rich cinnamon coloured bark, and the lovely dark green leaves that turn scarlet bronze in the fall.  Very few if any pests or disease bother it, but it does not like full sun and dry sites. Grow in fertile humus-rich moist but well-drained acid soil, best in part or dappled shade.

  • Seed Count: 20-25
  • Collection Date: Dec 2022
  • Hardiness Zone: 5-9
  • Height and Width: 2-3m x 2-3m
  • Germination test type: hand sort
  • Family:  Clethraceae

How to germinate Clethra barbinevis seeds:

No pre-germination treatments required. Surface sow; spreading seeds thinly over the prepared medium surface. Gently tamp seed into soil surface and mist. Seed needs light to germinate so don’t cover seed with medium.  A clear plastic cover to maintain humidity will greatly enhance germination and seedling survival. Give indirect light. Germinate at 25C. Medium should be humus rich and well draining. Should germinate quickly. Don’t let seedlings dry out as this is fatal until a better root system is formed after the 4th true leaf stage then gradually expose to normal conditions…that is wean them off the clear plastic cover.

Additional information

Weight 2 g