Nth. Am. Lilium
Jane McGary (Thu, 17 Jun 2004 19:32:05 PDT)

Perhaps it will help with Jim's and other people's approaches to western
American lilies to consider that the various species grow at quite a large
range of elevations. That is, some of them are effectively alpines (such as
L. washingtonianum, although there were at one time lower populations). The
timing of snowmelt, therefore, affects their growth cycles. And where they
don't get snow, they may get confused.

Even some of the southern Californian species are mountain plants. SOme
species, however, have an altitudinal range down quite low, such as L.
columbianum. L. pardalinum is another that can be seen from, I would guess,
about 2000 feet up to about 7000 feet.

Thus, just thinking about "Pacific Coast climate" is not much help when
approaching bulbs that may be restricted to habitats above the winter snow
line. (e.g., Erythronium grandiflorum and E. montanum, as well as some
lilies.) I pointed this out a bit when talking about the differences Ken
Hixson and I experience, when his garden is probably about 1200 feet lower
than mine, and I'm still below the alll-winter snow cover level.

Jim is right in supposing that spring in the Pacific Northwest is cooler
than in the Atlantic states. It's 90 F today, but two days ago the high was
65, and it had been chilly and wet for two weeks. A cool, variable spring
is typical of this region, and many bulbs take this in their stride.

So, the reason west coast growers have problems with west coast bulbs
generally lies in elevational differences and in where one resides relative
to the coast. For a good description of these factors, and for
corresponding chapters on other parts of North America, see the "regional"
section of "Rock Garden Design and Construction" (Timber Press, 2003).

Jane McGary
Northwestern Oregon, USA