Ceanothus thyrsiflorus var. thyrsiflorus 'Louis Edmunds' (Blue Blossom) - A prostrate evergreen groundcover shrub to 6 inches tall by 6 to 8 feet wide with small dark green leaves and clusters of light blue flowers in spring.
Plant in full sun to light shade. Tolerates both heat and drought. This is the lowest cultivated form of Ceanothus thyrsiflorus var. thyrsiflorus (what has long been called var. repens).
It was given to Rancho Santa Ana Botanic Garden as Ceanothus griseus 'Louis Edmunds' in 1958 (RSA 9759) by Louis L. Edmunds who operated Louis Edmunds Native Plant Nursery in Danville. This same plant was planted at the Santa Barbara Botanic Garden at the base of the Porter Trail where it performs admirably in dappled shade. The Rancho Santa Ana Botanic Garden (now California Botanic Garden also had another accession of Ceanothus thyrsiflorus var. thyrsiflorus (RSA 18882) that grows to 3 feet tall. This second plant was originally distributed by the Saratoga Horticultural Foundation as Ceanothus thyrsiflorus var. repens and had been reportedly growing in Ken Taylor's native plant garden in Aromas, CA and he had in turn had received the plant from Louis. Edmunds. At some point both of these plants, though quite different, collectively became known in the California nursery trade as Ceanothus thyrsiflorus 'Louis Edmunds'.
Adding confusion to this is the existence of another Ceanothus cultivar that was long sold as Ceanothus griseus 'Louis Edmunds'. With the most current revision of the genus that reduces the Ceanothus griseus to a variety of Ceanothus thyrsiflorus (Ceanothus thyrsiflorus var. griseus) the likelihood of confusion with all of the Louis Edmunds cultivars is ripe. In the excellent book Ceanothus by David Fross and Dieter Wilken, this problem is partly addressed by renaming the taller Ceanothus thyrsiflorus var. thyrsiflorus cultivar 'Taylor's Blue', but they did not describe the lower form that was also called 'Louis Edmunds'. While we liked how this plant looked, we realized it would never be possible to sort out which plant was the real 'Louis Edmunds', so we decided not to continue to grow it after first propagating it in 2003.
The genus name comes from the Greek word keanthos which was used to describe a type of thistle and meaning a "thorny plant" or "spiny plant" and first used by Linnaeus in 1753 to describe New Jersey Tea, Ceanothus americanus. The specific epithet means flowers in a thyrse, which is a compact cylindrical or ovate panicle with an indeterminate main axis and cymose sub-axes.
The information about Ceanothus thyrsiflorus var. thyrsiflorus 'Louis Edmunds' displayed on this web page is based on our research conducted in the nursery's horticultural library and from reliable online resources. We also include observations made about it as it grows in our nursery gardens and other gardens we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments we receive from others and welcome hearing from anyone with additional information, particularly if they can share cultural information that would aid others in growing this plant. |