Plant portrait: Centaurea jankae D. Brândză

Only about Centaurea jankae today; this species is too important to be mixed with other announcements.
Centaurea jankae is an endemic and extremely rare species, which can be found growing in steppe habitats only in Dobrogea, Romania and Bulgaria. In fact, two small populations exist in both countries.
It is a tall species with beautiful deeply-pinnately leaves and a multitude of large, magenta-red flowers, all summer long into late fall (the last flower was recorded in November).

I acquired very few, precious seeds by chance 5 years ago on the shoreline of Lake Razelm in Dobrogea, and understandably I was very happy for the chance to grow it.

Since then, it has flowered twice in my garden, every time as solitary plants. Despite the long flowering period and many pollinators visiting the flowers, no achenes were produced in both years. Self-incompatibility is often a problem in the Asteraceae family.
After flowering, it didn’t return in the spring, acting like a monocarpic species, and so the chances of maintaining it in cultivation were vanishing.

Update 2023: there are more plants now :) and of course more seeds. Not all plants behave monocarpic, it may differ if the garden location is suitable.

It is known that self-incompatibility is often exacerbated in very small populations, including for other Centaurea species, and in extreme cases it can even contribute to local extinction. In plain language, a very small population will contain too many ‘brothers’ and ‘sisters’ (of the same mother plant).

Luckily I had 2-3 seeds germinating every year; the germination is very easy (warm germinator) and the plants will flower after 2-3 years. This summer, 2 plants reached flowering stage. I was anxious, but…we got seeds (achenes)!

A lot of achenes can be empty and required very careful selection. However, a few seeds are all we need in most cases to perpetuate a species in cultivation.

Those having a sunny, well drained location in their garden, have the occasion now to follow me in growing the rare and beautiful Centaurea jankae! Conservation through propagation is one of our goals.

*The author of the species was Dimitrie Brândză, Romanian botanist and founder of the Botanical Garden of Bucharest.
**The specific epithet honors Victor Janka – Austrian military officer and botanist, which collected plants extensively throughout the former Austro-Hungarian Empire.