Stems grow three to ten inches tall from a slim, segmented rhizome where there are tooth-like projections on the root. Distinctly divided lance-shaped leaves arise in whorls of three with three to five narrow lobes and teeth along the edges. These hairless leaves are greyish green to medium green. Each leaf is about three inches long and across. One of the earliest-blooming spring ephemerals, the white, three-quarter inch flowers appear in a small cluster on the tip of an erect stem. Each four-petal flower is about a three-quarter-inch across with four green or purple sepals, several stamens that have yellow anthers, and one pistil. While characteristically white, the fragrant flowers can be tinted pink or light purple. Fruits are long, thin two-inch long pods. Within each pod, ovoid, somewhat flattened seeds come in a single row. Roots create a system of fleshy yet fragile rhizomes that are jointed, running shallowly parallel to the ground. By spreading these rhizomes, the Cutleaf Toothwort plant usually forms vegetative colonies. While much happens under the surface, this perennial is known as “a true ephemeral species” because it only puts on a show for a little more than a month above ground before the foliage turns yellow and the plant goes dormant. Hardy in USDA Zones 3-8, it is native to most of the eastern half of North America west. It appears in late April or early May in northern climates and a bit earlier in the south. Cutleaf toothwort has hybridized with large toothwort (Cardamine maxima) to produce Cardamine x incisa in northern and central states. This member of the mustard family will attract the first of the season’s bees. Sometimes, its nectar will even bring early spring butterflies. Unfortunately, Flea Beetles can also be attracted to the leaves.
Light
Find a spot that offers part shade. This plant blooms in dappled sunlight before the trees fill out and then requires part shade to full shade in summer.
Soil
Give Cutleaf Toothwort moist to mesic, humusy, well-drained soil. To mimic its native rich deciduous forests, add decaying leaves for extra nutrition. Other habitats include floodplain woodlands, wooded bluffs and upland savannas where likely the soil has never been plowed or disturbed by construction. Still, this plant can survive a few animals paws passing through or the occasional human seeking to harvest its tubers.
Water
Medium watering is recommended. In the proper environment, this perennial should receive enough water to thrive independently.
Propagating Cutleaf Toothwort
Cutleaf Toothwort will naturalize by rhizomes and form colonies. Dig up the fragile rhizomes carefully and divide or sow seeds freshly. Seeds need a period of cold stratification. Blooms appear in three to four years from seedlings.