Finally got it in a pot. This is clematis ligusticifolia, 'Western White Clematis', blooms in midsummer. Its a perrenial, so am I right to assume I can treat it like any other perrenial and whack off any bits that get out of bounds? That would be any attempt to overgrow my neighbor's shed. Mobile home lots are small and close, donchano. Now to figure out exactly WHEN midsummer might be around here, I guess it will be whenever the clematis blooms. Reading this forum is making me want more of them.