Linaria vulgaris (Yellow Toadflax)

Linaria vulgaris (Yellow Toadflax) is an erect perennial boasting masses of bright yellow or cream snapdragon-like flowers from late spring to the first frosts. They are borne in terminal clusters on stiff stems bearing narrow, pale green leaves arranged in a spiral. Each blossom features an orange spot on its lower lip and a small straight spur. Attractive to bees, butterflies, and other insects, the flowers are followed by round, dark-colored seeds that may disperse over a long distance in the wind, or may be moved by water and ants. Yellow Toadflax also spreads aggressively by runners. The roots of a single plant can extend 10 feet (3 m) and give rise to other plants every few inches, making it difficult to eradicate. This handsome perennial weed is listed as a noxious weed in several western US states and Canadian provinces. It should be used with caution.

• Grows up to 2 ft. tall (60 cm).
• Thrives in full sun in moderately fertile, light, well-drained soil. Prefers sandy soil.
• After flowering, plants can be cut back to prevent self-seeding.
• Keep an eye out for aphids, and powdery mildew. Yellow Toadflax is deer-resistant.
• Propagate by seed in pots in a cold frame in early spring. Propagate by division or softwood cuttings in spring.
• Native to Europe, southwestern Asia.
• Find where this species is invasive in the United States.