I've had 'dahlia imperialis' (double whites and single lavenders) in my garden for a few decades. From seemingly out of nowhere, the garden is sprouting healthy, prolific dark purple singles with bright yellow boss--and I've been at a loss as to what kind of dahlia they are and how they just appeared miraculously. I did just watch a YouTube video that showed ones that look just like my new ones, calling the variety 'excelsa' and remarking how "promiscuous" they (all dahlias?) are--Is that what I have in my garden? Is the 'excelsa' a variety of the 'imperialis'? See pic--
Thanks-- Torbie in San Francisco
