Asclepias latifolia aka Broadleaf Milkweed

Asclepias latifolia is also known as broadleaf milkweed. It belongs to the plant family called Apocynaceae. This perennial lives for more than two years. It comes from temperate parts of North America. Its native range covers the west-central and central United States. It reaches south into Chihuahua and Coahuila in Mexico. U.S. records list Kansas, Nebraska, Oklahoma, Colorado, and New Mexico. They also list Texas and Arizona. Other sites lie in southeastern California and southeastern Utah. It grows wild on dry plains and prairies. It is not native to Britain or Ireland.

Broadleaf milkweed grows upright and suits garden beds. Plants For A Future gives a height of 2.6 feet [0.8 metres]. The sources give no width for a full-grown plant. Nor do they describe the leaves in detail. Chicago Botanic Garden lists white and green flowers. The recorded bloom season runs from May through June. Each flower has both male and female organs. Bees, butterflies, moths, and other insects pollinate the flowers. The evidence gives no fruit details for this species.

Chicago Botanic Garden calls for full sun and dry soil. It lists USDA hardiness zones 4–9 for this plant. Plants For A Future says it tolerates light shade. It lists sandy soil that drains well as suitable. The plant can also grow in soil with few nutrients. The stated soil pH range runs from mildly acid to mildly alkaline. That source lists both dry and moist soil as suitable. Taken together, these records support sun and soil that drains well. Chicago Botanic Garden suggests beds or borders as uses.

Plants For A Future describes sowing seed in a greenhouse. It gives autumn, late winter, and early spring as sowing times. Stored seed may need two to three weeks of cold treatment. It reports that seeds sprout in one to three months at 18°C. It advises keeping young plants under glass through their first winter. Plant them out while they grow in late spring or early summer. Its broader growing notes draw on the needs of milkweeds in general. They do not draw on trials of this species. Those notes do not show this species' pest risks. Nor do they show its hardiness in Britain.

Plants For A Future records no known uses as food. It reports past use of ground leaves and stems as medicine. People breathed in this powder as snuff for catarrh. This record does not show that the use was safe. Nor does it show that the treatment worked. Latex from the leaves and stems can supply rubber. The supplied evidence does not confirm whether this species is toxic.