LINARIA. Toadflax. Widely distributed, mostly in the Northern Hemisphere. In spite of the images conjured by their common name, the linarias are a group of showy annuals and mostly short-lived perennials, usually easy to grow and offering generous displays of bright, cheery blossoms. They usually have slender stems, lined with brushes of narrow leaves and tipped with spike-like clusters of small flowers. These resemble the related snapdragons in form, except for a more conspicuous spur at the base. They often self-seed in gardens but offer little competition to neighboring plants. Sun, well drained soils, moderate to occasional watering. Hardiness varies.
alpina. This is my personal favorite, and certainly one of the most suitable for the rock garden. It makes a low mat, with slender stems and tiny bluish green leaves. From late spring to fall the recent shoots are tipped by tight clusters of violet flowers, marked with orange. It may live only a single season but is easily restarted from seeds.
purpurea. A perennial with erect 2-3 stems, closely set with bright bluish green leaves. In summer and fall they are dressed with spikes of 1/2" blossoms, purple in the typical form but varying to white. Canon Went is a seed strain with consistently light pink flowers. Below 0oF.
supina. A mounding perennial similar to L. alpina, above. It forms a loose mound under 1' high and perhaps 2' broad in time. Both stems and leaves are colored light bluish green. The plant is nearly everblooming, provided spent flower clusters are removed from time to time, and displays bicolored blossoms painted purple or maroon to yellow in small clusters. Probably 10oF or less.