Silphium integrifolium (Wholeleaf Rosinweed)

Silphium integrifolium (Wholeleaf Rosinweed) is a coarse perennial with erect stems sparsely clad with pairs of rough, oval to lance-shaped, medium green leaves, 6 in. long (15 cm). Blooming for 4-8 weeks in midsummer to early fall, clusters of showy daisy flowers, 2-3 in. across (5-7 cm), with yellow rays surrounding a yellow central disk, appear above the foliage. Each blossom is subtended by bracts with reflexed tips and borne on reddish to green stems. Attractive to butterflies and birds, the flowers are followed by large, flat seeds that can be carried several feet by the wind. Rosinweed has a fragrant resin while in flower, which was chewed as gum by Amerindian children, hence the common name. Silphium integrifolium is a stout perennial for the back of the perennial border and a great choice for prairie reconstructions or other natural plantings.

• Grows up to 2-6 ft. tall (60-180 cm) and 1-3 ft. wide (30-90 cm). Will self-seed where happy.
• Performs best in full sun or light shade in average, mesic to dry, well-drained soils. Tolerant of a wide range of soils, including sandy soils or clay soils. Drought tolerant once established.
• No serious pest or disease issues. Keep an eye out for downy mildew, leaf spots or rust.
• Great for prairies or meadows, cottage gardens, wildflower gardens.
• Propagate by seed. Sow unstratified seed in fall or stratified seed in spring.
• Native to the central United States and Ontario in Canada