The small, tubular, blue-violet flowers of Blue Vervain bloom from the bottom up in July’s heat. The numerous crowning spikes of blossoms give a candelabra-like appearance to this graceful, widely-distributed plant. As the alternative name Swamp Verbena suggests, this Vervain likes wet, even soggy, conditions but also will grow in medium soils. Full sun to partial sun are its preferred sun conditions. It is a rough, clump-forming perennial with a stiff, upright habit which typically grows 2-4′ tall (less frequently to 6′) on square hairy stems which typically branch above. Features candelabra-like inflorescences of erect, slender, pencil-like spikes (2-6″ long) of tiny, tubular, 5-lobed, densely-packed, purplish-blue flowers (1/8″ wide) which appear over a long July-September bloom period. Flowers on each spike bloom bottom to top, only a few at a time. Lance-shaped, sharply toothed, green leaves (to 6″ long).
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