In the last issue I discussed three vines recommended by Jim Knopf for serving the special needs of the Boulder-Dushanbe Teahouse arbors. These vines were Clematis tangutica, Bokaravine Fleeceflower, and Riverbank Grape. Because the legs supporting the arbors are 12’-15’ tall, only the most cold-hardy and vigorous vines could be used.
Now I am going to discuss the other three vines that we chose to fulfill those same requirements: Clematis ternifolia, the Sweet Autumn Clematis; Wisteria macrostachya, the Kentucky wisteria and Ampelopsis aconitifolia, Monkshood Vine.
Sweet Autumn Clematis is one of the small-flowered species varieties that blooms profusely with white flowers in the fall. Much variability exists and some are very fragrant and some have little fragrance. This variety is from China and Japan and is said to appreciate our summer heat. It is very vigorous to 30’ and has smooth, dark green, roundish leaves. The flowers are 4-petaled, star-like and white with a burst of yellow stamens and are borne in clusters called cymes. These are followed by fluffy silvery seed heads. In the past it has been known as Clematis paniculata and Clematis maximowicziana.
Wisteria macrostachya, the Kentucky Wisteria is growing in a few locations in Boulder. The vine is less vigorous than the Japanese or Chinese varieties, still growing up to 25’ and twining counter-clockwise (viewed from above). The flowers are 5-petaled and pea-like in clusters from 5”-10” long. They are pale violet with mauve, reddish purple and a little yellow, though many variations occur. The flowers bloom later than the other wisterias which is a mixed blessing since even though it means the flowers are less often destroyed by late freezes , they are also less visible since they bloom amongst the leaves. The fragrance in subdued compared to other varieties. The pods which follow are velvety, about 3”-5” long and twist open with a bang, throwing its seeds. It is said to be tolerant of wet soils.
Monkshood Vine, Ampelopsis aconitifolia is from northern China and is far more vigorous than its better-known cousin, the Porcelain Vine, growing to 30’. The beautiful leaves resemble Monkshood and whereas the flowers are indistinct, the berries when ripe are orange or yellow and in clusters. At the Teahouse, this vine is competing with the Riverbank Grape for most vigorous vine on the arbor.
Each year I have reduced the number of shoots in the lower half of all the vines and have lifted and tied the upper shoots to get them to grow taller faster.