Ann wrote:

: They grow as far north as Middleton, NH, which is zone 5a, I believe.
: I don't think you need to do anything to them to keep them, they grow
: where they're happy ) I've seen them in several places around here
: in New England, all in moist, woodsy soil, and while I've never done a
: pH test, I'm sure the soil is very acid.

I have seen it in Finland growing on dry limestone cliffs.
Unfortunately, it is not an weed in Europe.

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Erkki 'Örkki' Aalto "Life is divided up into
Internet: the horrible and the miserable"
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