Mark McDonough pointed out the persistent nature of Tulipa tarda in his New England garden. It is the same here (until the voles find it). This isn't very good tulip country either, owing to the wet winter/spring weather, but some small species tulips seem relatively permanent and increase: Tt. urumiensis, hageri, humilis 'Lilliput' (I suspect that clone is not T. humilis, however), linifolia, eichleri, saxatilis, sylvestris, and clusiana. Most of these do best in a rock garden situation, but T. sylvestris likes a moister, more retentive soil. T. clusiana is well known for its adaptability to warm Mediterranean climates; I gave my mother some that spread nicely among really aggressive tree roots. A delightful tulip species that is not seen much in North American gardens is T. sprengeri, which flowers very late, usually in June here. It is a medium-sized bright red one that is apparently difficult to propagate in the usual way; I believe it makes very tiny offsets, perhaps on stolons. Seed is readily available, however, and I've raised a few that way. Jane McGary Northwestern Oregon, USA