I love discovering more about plants! My students seem to have this notion that I am a walking botanical encyclopaedia. But this is, of course, far from the truth.
Yes, I am quite au fait with plants growing in the average garden, but whenever I visit a botanical collection or a plantsman’s garden my camera and my field book will be working over-time!
Yes, the more you know the more you come to realise you have not scratched the surface!
There is, however, one plant that I have noted on more than one occasion in late summer and early autumn, always meaning to find out more about it…
A deciduous shrub of 3 metres or so, often growing in a light woodland type area and looking like it would not normally stand out from the crowd – except at this time of year when it is adorned with bunches of fat broad-bean-like pods of a most wonderful blue (pictured).
But although well intentioned, I had never got round to looking it up – until this week when a fellow gardener bought me some pods. No excuse now!
The plant in question is called Decaisnea fargesii, and common names include the, not surprising, Blue Bean Shrub and Blue Sausage Fruit. A more freaky name, however, is ‘Dead man’s fingers’ – as the finger-like fruits are soft to the touch and covered with an eerily cold, skin-like peel. So sorry I could not have written this in time for Halloween!
Even more surprise when you split open the fruits – they unzip a little like a banana, except only on one side. Inside is a translucent gelatinous pulp into which the flat black seeds are embedded. The jelly-like pulp is edible, a bit like a sweet cucumber or melon. Apparently it has been enjoyed as a delicacy for centuries by the Lepcha, the indigenous people of Sikkim, northeast India. At home in much of East Asia and West China it happily grows at altitudes between 900 and 3500 metres above sea level, which is why it is quite hardy here in the UK.
The fruits may be eye-catching, but the same cannot be said of the flowers. Six narrow star-like petals of greenish-yellow, borne in dropping racemes of separated male and female flowers. Unusually each female flower contains three separate carpels, but these separate after successful pollination into three individual fruits – correctly called ‘fruitlets’ as they are derived from the one flower. So a dead man with only three fingers. Uurgh!
Seeds from fleshy fruits, such as these need to be cleaned of all the fruit before saving. The easiest way is by using a kitchen sieve to wash the pulp away before thoroughly drying any seeds we wish to store. These will be kept in a cool, dry place – actually in an airtight container in the fridge, until spring.
We will also be sowing some of the seeds now, covering them with grit and placing them in the unheated greenhouse. Consider their natural habitat – they are not going to require a heated propagator!
n Manea School of Gardening (RHS approved centre). Plant sales on Saturdays 10am-4pm.