Cosmos atrosanguineus 'Thomocha' CHOCAMOCHA
18th June 2014
Cosmos atrosanguineus was introduced to the UK in 1835. Seeds were sent from Mexico to Zurich Botanic Garden and also to William Thompson of Ipswich (later to become Thompson and Morgan).
The remarkble dark maroon flowers are produced through the summer and it produces a tuberous root that can survive the winter in a favoured location. Easily rooted from cuttings
but young plants need a whole seasons gowth if they are to produce tubers. Cuttings rooted later in summer do not usually survive.
For many years it was represented in cultivation by a single male-sterile clone and it was thought to be extinct in the wild. Fortunately in 1990 Russell Poulter,
a genetecist at Otago University in New Zealand, noticed a plant that had produced two seeds. Crossing among the plants produced a small population of fertile individuals
and eventually he introduced a strain called 'Pinot Noir'.
In 2006 Topmpson and Morgan introduced a hybrid with an unidentified species called 'Thomocha' (sold as CHOCAMOCHA). I planted it in the Agave house where it prospered for a couple of years,
often producing pinkish flowers at the start of the growing season, turning darker later in the year.
It is said to be less reliably perennial and less tuberous than the original clone. It grew well for a couple of years here but didn't appear again in the third.
12h October 2015