The American prairie onion, Allium stellatum,
is receptive to hybridization, readily
crossing among variable forms of the same species, with A. cernuum, and
surprisingly, with European and Asian rhizomatous alliums such as
and senescens. Such hybrids show a tendency for greater stem height,
fold increase in number of flowers in the inflorescence, densely arranged
and thicker and broader foliage revealing the obvious genetic influence.
Shown below is one of the first spontaneous crosses found in my garden,
is clearly a cross between A. stellatum and A. senescens. The florets are
numerous that they barely have enough room to open, in fact,
the flowers don't open properly and the flower head looks distorted. Stems
reach 24"-28" tall. Photo taken on the last day of July.
Allium 'Rosy Affair' is a another stellatum x senescens hybrid,
this one with neat growth and bright
rosy pink flowers on 16" stems , putting on a display from late July
and well into August. The gray
foliage twists, just like its parent, Allium senescens. Photo below
taken early August.
In the image below, we see a typical inflorescence of Allium stellatum on
the right, with the
sideways open spray of widely spaced starry florets. On the left are
two spontaneous seedlings
that appeared growing up among a swath of typical stellatum. The
flower heads have more
florets in a much denser knob-like head, showing the influence of nearby
beds of mixed
rhizomatous hybrids (nutans, senescens, and angulosum). They have
conspicuously larger green ovaries, typical in such interspecific
hybrids. I dubbed this plant
Allium "Tall Hobnob" (grows 24" tall or more), yet had
a similar hybrid appear that is
much smaller in growth, and only 8-10" tall, which I nicknamed
Allium 'Applemint' (stellatum x nutans/senescens) - newly selected in
2007. This robust stellatum hybrid has
27" tall stems, and over 90 florets per flower head, flowering for a
long period from late July through late August
(photo taken August 23, 2007). Unlike some hybrids where the
developing fertilized seed capsules turn brown,
here they stay a fresh green, which compliments rather than detracts from
the flesh flowers and developing buds.
The strong grayish foliage twists, showing close alliance with the many
nutans/senescens hybrids nearby.
Notice the three pairs of crests on the top each seed capsule, a strong
characteristic of A. stellatum.