Eranthis pinnatifida - plant of the month January 2018
Eranthis pinnatifida is one of eight (possibly nine) species of plants collectively known as 'winter aconites' and like Aconites they are poisonous in all their parts.
E. pinnatifida is endemic to Japan and according to Ohwi, distributed on Honshu westwards from Kanto. Known erroneously as Shibateranthis pinnatifida and Eranthis keiskei, E pinnatifida has large white flowers with broad slightly overlapping sepals and bifid petals tipped yellow. The bracts of the involucre are pinnatifid and the rhizome (tuber) is globose.
Above: First year and second year seedlings - flowering should commence in the third year.
Like most Eranthis species, E pinnatifida responds well to being grown in a sharply drained, humus-rich compost kept evenly moist. Propagation by seed is the easiest, usually flowering in the third year from sowing - beloved by slugs and snails, its best to take preventative measures against them. Division is possible but tricky as the growth points, or 'eyes 'are difficult to see prior to root initiation when the rhizome is best left undisturbed.
Despite its appearance, Eranthis pinnatifida is extremely tough and needs to be grown 'hard' to keep it in character; too long under glass leads to thin, etiolated growth where much of its charm is lost. It does however make a good subject to brighten up dark winter days when brought into in the alpine house when in flower. In late seasons, it also makes for an eye-catching display as a show plant.