Weekend Plantings: Potato Tree, Native and Exotic Milkweeds, The Well-Named Stinkhorn

Among the largest and most ornamental grasses for our landscapes is tiger grass (Thysanolaena maxima), an 8-to-10-foot-tall species native to Nepal, India and Bhutan. Introduced from Sumatra to the United States by plant explorer David Fairchild, this tightly clumping perennial grass serves as an accent, screen or part of a shrubbery border. It's a fast-growing species that resembles bamboo but is neater in appearance.

Tiger grass, wonderfully tropical in appearance, features slender stems topped by wide leaves that arch languidly to produce a fountain effect. In addition, lovely purplish flowers — made into brooms in Southeast Asia — are displayed much of the year. Native to hilly, well-drained regions, tiger grass thrives on fast-draining sites in full or part-day sun. Young specimens should be fertilized two or three times annually during the growing season. Irrigate juvenile plants thoroughly on a regular basis during dry periods in spring and autumn. In Central Florida, tiger grass is evergreen unless there's a freeze or extended period of frosty nights. Regrowth in spring is rapid. Propagate by division.

POTATO TREE

You don't need a potato peeler or other kitchen paraphernalia for the potato tree: It's strictly ornamental. Native to Bolivia and Brazil, the potato tree, a relative of the Idaho potato, is a 10-to-20-foot-tall evergreen tree that bears clusters of 2-inch-wide, star-shaped flowers from spring into autumn. The blossoms, borne at the tips of prickly stems that carry large-lobed leaves, open purple and fade to white. This sun-loving tree (Solanum wrightii) requires well-drained sites that are moderately enriched with organic matter. Early-spring fertilization is recommended. Propagate with seeds during the warm season.

NATIVE AND EXOTIC MILKWEEDS

The most widely sold and cultivated species of milkweed (Asclepias) is Mexican milkweed (A. curassavica), a short-lived perennial that grows 2 feet tall and bears fleshy flowers that can be orange and yellow, or all scarlet, or yellow. This plant requires sandy, fast-draining soil and bright light. Mexican milkweed has received some negative publicity because of a single-cell parasite that lives on old leaves and attacks monarch butterflies. But researchers have found this parasite on the older leaves (at least a year old) of all species of milkweeds, including natives. Therefore, all milkweed plants should be cut to the ground each spring so they can grow new, parasite-free foliage.

THE WELL-NAMED STINKHORN

If you spend much time gardening, you've probably seen — and smelled — a stinkhorn fungus or two. This harmless fungus lives on decaying organic matter, where it grows from a spore into an egg-shaped membrane that eventually tears to expose a reddish mushroom. The short-lived mushroom quickly turns into a smelly, gelatinous blob that attracts flies, which spread the stinkhorn spores and perpetuate the cycle. To interrupt that cycle, dig up and bag the mushrooms as soon as you spot them.

[ Charles Reynolds has an associate's degree in horticulture and is a member of the Garden Writers' Association of America. ]