Lilies and Related Plants - RHS Lily Group

stemlets – peduncles – that dangle this plant’s lovely fruits before the creatures who
will devour, distribute or at least photograph them.
There may be 10 Streptopus species, give or take a taxon in Asia. They all look
broadly similar and dwell in wet, temperate climates (I was taken aback recently to
learn of S . chatterjeeanus, S. Dasgupta 2003, described from the Himalaya, but it
turns out to grow at rainy elevations).
In North America there are just three Streptopus species, all easy to grow, in my
experience.
Streptopus lanceolatus (“lance-leaved”, formerly S. roseus) is the only species
with pink flowers, and quite variable. Its berries ripen red to purple and it may
branch or not. Widespread in the northeast and in the far west, it prefers moist,
lower-elevation woods. On montane trails Near Whistler, BC, several beautiful
color forms of this species occur. I keep meaning to go back there and select not
only for color but for height and branching pattern.
Streptopus amplexifolius (“clasping-leaved”) is just as variable, with many forms
worth selecting. Its flowers are green to beige with red markings, its berries ripen
to purple-black and it always branches. Common in much of the east and west, its
range excludes the centre of the continent and the southern United States.
Streptopus amplexifolius in our garden grows perhaps 18in (50cm) tall. On the
west coast of Vancouver Island, in damp old forest along the Clanninick River, it
attains a similar height. In a wetland in the very rainy Columbia Mountains, however,
near Revelstoke, BC, I was astounded to see crowds of amplexifolius towering
above stupendous, 5ft (150cm) skunk cabbages (Lysichiton americanum). Again,
as a service to horticulture, I simply must go back.
Streptopus streptopoides (“Streptopus-like indeed”) is a charming, unbranched
creeper, usually shorter than your thumb though occasionally it bolts to 8in
(20cm). It has red berries and small, wine-and-green flowers that resemble
flattened turbans. Var. streptopoides, with hairless leaf margins, grows in scattered,
damp coniferous sites in an arc from BC through Alaska to Siberia and northern
Japan; var. japonicus, with hairs on its leaf margins, is native to northern and
central Honshu, Japan’s main island. I have grown var. streptopoides in a trough
with rock plants, but it should do well with rain loving lilies and frits too. For scale,
I think I’ll try the dwarf form of Fritillaria camschatcensis.
This was a bad year for seed of Streptopus amplexifolius, but I’m sending lots of
seeds of Prosartes hookeri to the lily-group exchange. Watch for them.
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