Cypripedium californicum - plant of the month May 2014
With 47 known species, the Genus Cypripedium has a widespread distribution throughout much of the temperate regions of the northern hemisphere. The genus is divided into 13 sections in which C. californicum is the monotypic member of section Californicum (Z J Liu, P J Cribb & Y B Luo). C californicum has an extremely narrow distribution being confined to southwestern Oregon and northern California in wet places by steep mountain streams and springs, usually at elevations between 450 and 1600m and often in the company of the carnivorous pitcher plant Darlingtonia californica.
Distinguished by its many-flowered stems of bicoloured, dove-egg like flowers, some with a pronounced red/pink flush on top of the more normal white pouch with greeny-brown petals, dorsally pubescent sepals and petals and convex staminode making it impossible to mistake with any other species, though many man-made hybrids are flooding onto the market and who knows what the future may bring. Well grown specimens can reach over a metre in height forming large clumps which flower anytime from June to August in the wild.
First introduced into cultivation in the British Isles in the late 1800's, it is said to be a rather difficult species to grow and even more challenging to flower well. It requires plenty of moisture during the growing season but will not tolerate a wet, cold winter - some advocate a frost-free environment but I have found it to be OK if kept cold and sheltered ( against a north facing wall with a glass cover to protect from winter rains). The compost requirements vary according to which of the above treatments are chosen - I prefer a mix based on leaf mould, bark and perlite using plastic pots.
'Cyps' are now becoming more readily available with the advent of plants arriving from the European continent, C californicum being amongst them but it is probably best to say that this species is not really one for the beginner.