Argemone albiflora aka Bluestem Pricklypoppy

Argemone albiflora is known as white prickly poppy or bluestem pricklypoppy. It belongs to the poppy family, Papaveraceae. Its native range runs from the southeastern United States to eastern Texas. Kew lists it as a plant of subtropical climates. It grows as an annual or biennial, rather than a long-lived perennial. Records place it on roadsides, fields, beaches, dunes, and coastal plains. It also grows on waste ground, from sea level to about 984 feet [300 metres].

This upright plant reaches about 1.6–3.3 feet [0.5–1 metre] in height and spread. It takes one to two years to reach full size. Its dark blue-green leaves have a prickly, thistle-like look. The foliage is deciduous. Crushed parts release a milky sap, which can irritate skin. Wear gloves and other protective clothing when handling the plant. Its spiny leaves and upright shape give it a clear presence in mixed planting.

Large white flowers open in summer, with yellow to red centres. Their form recalls that of other poppies. Each bloom lasts only a short time. New flowers keep the plant in bloom as older ones fade. The pale flowers stand out against the dark leaves. RHS suggests it for cottage gardens and other informal settings. It also suits prairie planting, wildflower meadows, and wildlife gardens. Plants can grow in cultivated beds as well.

Choose a sheltered site with sun or partial shade. Sandy soil with good drainage suits this species. RHS lists both moist, well-drained soil and freely drained soil. It accepts acid, neutral, and alkaline conditions. RHS rates its UK hardiness as H4. Plants For A Future lists USDA zones 6–9. Raise plants from seed; they also seed themselves readily where they grow. They need no pruning. RHS reports few routine problems with either pests or disease.

This is not an edible plant. Plants For A Future gives it an edibility score of zero. All parts, including the seeds, contain toxic alkaloids. The same source records past medicinal uses for leaves and plant infusions. These include treatments for skin complaints, wounds, colds, and jaundice. Such records do not establish that home use is safe. The source warns that seed oil can cause glaucoma and swelling. Its value in the garden lies in its flowers and form, not food use.