Leptinella squalida 'Platt's Black'
Common Name: brass buttons 
Type: Herbaceous perennial
Family: Asteraceae
Zone: 4 to 10
Height: 0.00 to 0.25 feet
Spread: 0.25 to 1.00 feet
Bloom Time: June to July
Bloom Description: Yellow
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Ground Cover, Naturalize
Flower: Showy

Culture

Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Prefers acidic, organically rich loams. Intolerant of drought. Tolerates light shade, particularly in hot summer climates. Plants spread indefinitely by rhizomes/runners. In large plantings, spent flowers may be removed by a lawn mower if desired. Container plants may be spaced 9-12” apart when planted as a ground cover. Propagate by division in spring or fall. Foliage is evergreen in USDA Zones 9-10.

Noteworthy Characteristics

Leptinella squalida, commonly called brass buttons, is native to New Zealand. It is a rhizomatous, mat-forming perennial that grows to only 2” tall but spreads indefinitely by runners. Button-like yellow flowers in early summer are followed by tiny fruit. Neither the flowers nor the fruit are considered to be particularly ornamental. Delicate, soft-textured, fern-like, oval green leaves (each to 2" long and 1/2" wide) are evergreen in USDA Zones 9-10, but deciduous in the St. Louis area. Foliage will tolerate some foot traffic. Synonymous with and formerly known as Cotula squalida.

Specific epithet means dirty.

‘Platt’s Black’ is a cultivar in which the unusual near black foliage is the real attraction.

Problems

No serious insect or disease problems. Some susceptibility to verticillium wilt, leaf spots and stem rots. Aphids, mites and leaf miners are occasional visitors.

Uses

Small area ground cover for sunny spots in the landscape. Rock gardens. Species plants (green foliage) are sometimes grown between stepping stones or used as a turf substitute, particularly in areas where plants are evergreen. The dark foliage plants are perhaps better grown ornamentally in gardens.