Parallel regions

Jane McGary
Fri, 20 Nov 2009 11:38:03 PST
Jim SHields's list of plants that he considers diagnostic of his 
region (central Indiana) is a good example of how difficult it is to 
use the word "hardy" without qualifying it. Even though I live in an 
area that is warmer in absolute terms (i.e., winter lows) than where 
Jim is, I can't grow Crinum or Lycoris outdoors, and he mentions a 
number of species in these genera that do well for him. I think the 
difference is mainly summer humidity, which is low here in the West, 
resulting in sharp night temperature drops even when daytime 
temperatures soar into the 90s F (c. 35 C). I would not call these 
plants "hardy" in western Oregon, but obviously they can survive 
colder winters than we normally have, as long as they enjoy the sort 
of summer climate they evolved in. I've learned through the years and 
many killed plants to be wary of species from southeastern North 
America and East Asia, especially Japan. I expect I'll be able to 
grow them better once I move from my rural property in the Cascades 
foothills to a close-in suburb about 1200 feet lower down, and within 
the range of the "urban heat island," where night temperatures don't 
drop so sharply. I know that, for example, Iris cristata grows well 
in Portland though it fades away up here.

On the other hand, Jim's list contains plants that come from "my" 
climate rather than from "his" -- Chionodoxa, Colchicum speciosum, 
the crocuses, Narcissus calcicola, and Sternbergia lutea. They must 
thrive partly because Jim has given them special conditions, and 
partly because these are naturally very adaptable plants, much as the 
East Asia hostas adapt well to my garden despite their ancestral range.

Jane McGary
Northwestern Oregon, USA

Jim's list
>How about approaching this from the point of view of what species are hardy
>in a given location, e.g., central Indiana in my case?
>I can grow the following here, with survival times of several years or longer:
>Arisaema heterophyllum, stewardsonii*, triphyllum
>Chionodoxa lucilae
>Colchicum autumnale, byzantinum, cilicicum, speciosum
>Corydalis angustifolia, solida
>Crinum bulbispermum, variabile
>Crocosmia 'Lucifer'
>Crocus tommasinianus, nudiflorus, cartwrightinaus
>Fritillaria acmopetala, crassifolia kurdica, pallidiflora
>Galtonia candicans*
>Gladiolus caucasicus, imbricatus, italicus, oppositiflorus salmoneus
>Hemerocallis coreana, dumortieri, minor, thunbergii
>Iris delavayi, sanguinea, setosa, siberica cvs., tectorum, versicolor
>Lycoris caldwellii, chinensis, longituba, sprengeri, squamigera
>Narcissus calcicola*, obvalleris, large-cup cvs.
>Scilla siberica
>Sternbergia lutea
>Trillium sp.
>* indicates survives in restricted locations

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