kreemoweet said: That's odd, because I've been growing tarragon outdoors in various locations in Seattle for close to 30 years, in the open and in pots. It always comes back from the underground parts in the Spring. It gets no special treatment. Sometimes it's been difficult to keep it going in locations that get too dry in Summer. Perhaps you've just been getting clones that are especially frost-tender.
kreemoweet, that's wonderful to hear! Hadn't really considered planting it outside so will try that this year. Do you have any recommendations as to the conditions it seems to do best in?
French tarragon (the culinary variety) doesn't set seed (it's got some sort of chromosome anomalies compared to the "wild" species), and must be propagated vegetatively. No doubt there are many different cloned strains.