Asclepias incarnata 'Ice Ballet' (Swamp Milkweed)
Outstanding native that grows to about 4-5' tall and rather than the typical pink flowers, this one is a clear white, with an unusual cinnamon/vanilla scent. One of the very best plants for attracting and supporting not only monarchs but a long list of native butterflies. Likes sunny moist settings. Deadhead for repeat blooms. Makes a great cut flower too.