Lithospermum incisum aka Fringed Gromwell

Lithospermum incisum belongs to the borage family, Boraginaceae. It is a perennial, so it lives for years. People call it fringed puccoon or narrowleaf stoneseed. Kew places its native range in the central and southern United States. This range extends into northern and western Mexico. PFAF gives a wider range, including parts of Canada. It grows on dry plains, foothills, and mountain ridges. These sites reach about 6,890 feet [2,100 metres] above sea level.

The plant grows upright to about 1 foot [0.3 metres] tall. Its small size suits beds and borders. Yellow blooms give the main spring show in gardens. Chicago Botanic Garden lists bloom from March through June. PFAF gives June as the month it blooms. The first flowers are large and showy. Later, many small flowers form but stay shut. These fertile flowers, called cleistogamous flowers, can set seed while closed. Insects pollinate the open flowers. Each open flower has both male and female organs.

Give this plant a warm spot in full sun. PFAF says it does not grow in shade. It needs soil that drains well, with a moderate level of nutrients. Both sandy soil and loam suit it. Choose neutral soil or soil that is slightly alkaline, not acid. Chicago Botanic Garden says it prefers dry soil. PFAF says moist soil also suits it if it drains well. Chicago lists USDA hardiness zones 5–7. PFAF gives a separate UK zone rating of 3. This is not a rating on the RHS H-scale.

PFAF lists cooked roots as a minor food use. People have boiled or roasted them and made root tea. PFAF also records how Indigenous North American peoples used it as medicine. They used root preparations for colds, stomach pain, and kidney complaints. Other records describe eyewashes and use as an oral contraceptive. These past uses do not prove that treatments are safe. PFAF lists no known hazards. This does not mean every use is safe.

The plant has craft uses as well as garden uses. Its roots have supplied red and blue dyes. People have used the seeds as beads. They have burned the dried tops as incense, too. PFAF does not flag this plant as weedy. It lists seed, cuttings, and division as ways to grow new plants. It says to sow seed in spring in a cold frame. Young plants spend their first winter under glass. They then go into the ground once frost has passed.