Leadplant

Size, growth and what to expect

Leadplant is slow above ground, and our growth estimator models it at a few inches a year on an average site, slowing as it nears full size. Restoration researchers report slow growth because the plant puts its effort into a root that reaches 7 to 20 feet down. Mature plants stand 1 to 3 feet tall and spread 2 to 2½ feet. The stems die back each year and sprout again from a woody crown. Seedlings take about 4 years to reach flowering.

A grown plant can carry up to 30 flowering stems and 3,000 flowers in late June and July. Solitary bees are its main pollinators, and the endangered Karner blue butterfly takes its nectar. Each small pod holds one seed. The name comes from the leaves, which look dusted with lead under their fine gray hairs. Cattle and browsing wildlife find it highly palatable, so it needs protection.

It grows wild across most of the Great Plains, from Manitoba south to Texas and from Indiana west to Wyoming and New Mexico, on well-drained prairies, rocky bluffs and open woods.

How to grow Leadplant

Leadplant is a full sun, dry soil plant and nothing else will do. It needs drainage above all. A bed that stays damp, or one watered with the lawn, rots the crown. It belongs at the front, 2 feet apart, among low neighbors.

Saplings ship bare-root or potted. Plant while dormant. Small plants take hold better than large ones, because the taproot goes down early and hates being cut. Dig a little wider than the roots, set the crown at grade, and refill with the soil you removed. Use a thin gritty mulch or a scatter of gravel, kept off the crown. Nothing this size needs a stake. Nick the hard coat and sow seed in fall in a screened bed, expecting slow, uneven germination.

Water the first summer, then stop. Deer and rabbits find leadplant delicious, so cage every new plant two years at least, longer where deer press hard. Cut old stems back to a few inches in late winter to keep it tight.

Leadplant sets seed only with pollen from another plant, so plant two or more seedlings from different parents. Almost nothing shows above ground for two or three years while the root drives down, and that is normal rather than failure. Rich soil and fertilizer only make it flop.