Heptacodium miconioides - Seven Sons Tree
Family - Caprifoliaceae
Size - Large, multistemmed, arching shrub to approximately 15', spread is about 1/2 the height. Grows approximately 1 1/2 to 2 feet per year. Although it can supposedly be trained to a treeform it doesn't give me the impression it will lend itself to development easily. I think it would be easier to run the bulls of Pomplona.
Foliage - Parallel venation, about 3 to 5 inches in length and 1 1/2 to 2 1/2 inches in width. Glossy green in summer. Foliage is very similiar in appearance to Forsythia or Honeysuckle, relatives of Heptacodium. Fall color is insignificant.
Flower/Fruit/Seed - Flowers are creamy white, slightly fragrant, born in clusters of seven, hence the name, hepta = seven and codium = head. Flowering time begins approximately the second week of August through early to mid September. After flowering, the calyx turn a cherry red and persist until the first hard frost. This can be an attractive feature of the plant in a good year, but for the most part I find it fairly unimpressive.
Bark - Reddish-brown outer bark peeling away in thin narrow strips revealing beige tones underneath.
Pests and Diseases - I have noticed some dieback on large canes which makes me wonder if there is susceptibility to a canker disease. This has happened on several occasions, twice resulting in the death of the entire plant. I spoke with Don Shadow, Shadow Nursery, Winchester, Tennessee and he confirmed the same thing. In my opinion, the significant amount that this canker problem seems to occur could seriously limit the use of this plant. It also seems to be injured by late freezes.
Landscape Use - Mixed border, hedge, small tree if trained. Makes a nice addition to the landscape in the late summer and fall when practically nothing else is flowering.
Performance - 7 Tolerates a range of soils from dry and sandy, to wet clays. Needs full sun for optimum development and flowering. Supposedly hardy to zone 5. It's too early to tell how actually limited by and susceptable to canker problems that this plant actually is, but we do know that it occurs. Whether or not cultural changes could alleviate any problems is unknown. It's not well known or used frequently enough yet to get a broad voice of opinion.