A poppy mallow is a genus of nine species in the Malvaceae, or mallow family, known as Callirhoe. They are all native to North America, generally growing in prairies or in rocky, disturbed soil. These perennials and annuals are often recommended to gardeners as heat-tolerant, low-maintenance, drought-resistant flowering plants. They generally form spreading mats and can be grown in a range of sunny situations, ranging from flower borders to rock gardens to prairies. Poppy mallows have extremely deep taproots.
The most commonly grown species is the purple poppy mallow, Callirhoe involucrata. This perennial plant only grows up to 1 foot (0.3 m) tall. It can spread to form a mat up to 3 ft (0.9 m) wide, however, that appears lacy due to indentations in the leaves. The flowers are purple and look like those of poppies, although they close during the night. They can grow to be 2.5 inches (6.3 cm) wide, and are produced from spring through fall.
If the stems are trimmed back in the middle of the summer, this encourages the production of new flowers. In cold weather, the plants die back to the crown. They species will re-grow in the spring, however.
Also known as winecup, the purple poppy mallow is easily grown in soils with good drainage. The soil can be dry or slightly moist, but if it is too wet, the plants are likely to succumb to crown rot. This is more likely to happen in soils with poor drainage.
The long taproot of the plant helps it to survive drought conditions. It makes established plants difficult to transplant, however. Native Americans ate the roots, which are reported to taste like sweet potatoes. This species of poppy mallow flourishes in hot weather. In deserts, the plant requires some shade and regular watering, however.
Poppy mallows can be planted from nursery starter plants or grown from seed. The seeds should be planted in the fall. If they are grown in a favorable environment, they often self-seed to produce additional colonies.
Another popular species of poppy mallow is the fringed poppy mallow, or Callirhoe digitata. Instead of growing as spreading mats, this plant grows upwards to 5 feet (1.5 m) high. It produces rose-colored flowers with fringes, usually in July.
A rare species is Bush’s poppy mallow, or Callirhoe bushii. Unlike the other Callirhoes, this species will grow well in light shade. The plant grows to 2 feet (0.6 m) tall. It typically starts producing its magenta flowers in the summer.