Ageratum houstonianum (Flossflower)

As a long-blooming, summer annual, this plant keeps a nice mounded shape throughout its bloom period. It is covered with clusters of small flowers. It comes in blue, pink, and white blooms. It generally grows about a foot high, though some dwarf varieties are available. Mass blue Ageratum is beautiful in beds with yellow marigolds for complementary colors, or with pink begonias to create a soft pastel carpet. Ageratum is very easy to grow in a sunny location.