The flower stalks, 18 inches to 5 feet tall, emerge from lush clumps of straplike foliage and are topped in bloom clusters in several shades of blue. White varieties also are available.

Ageratum (Ageratum houstonianum), also called floss flower, is a unique, warm-season annual with fuzzy flowers in blue, pink, purple, or white. “Ageratum has cute little fuzzy blooms that add a nice ...

After it flowers, deadhead lion's tail and prune the flowers a bit to make them look their best. Do this in late winter so that they'll be able to grow well once spring rolls around.