Cardamine angustata aka Slender Toothwort

Cardamine angustata, or slender toothwort, belongs to the mustard family, Brassicaceae. This herbaceous perennial comes from the eastern United States. In North Carolina, it grows mainly in the northern Piedmont. There, it lives on lower slopes in mixed hardwood woods. It grows from a rhizome and has an upright form. Its leaves and stems give it a fine texture.

Garden plants reach about 1.2–1.3 feet [0.36–0.41 metres] tall. They spread about 1–1.5 feet [0.30–0.46 metres] wide. The green stems often have a red tint. Most stems feel smooth, though some bear hairs. The leaves at ground level differ from those on stems. Each basal leaf has three broad, oval or diamond-shaped leaflets. Their edges have teeth. Basal leaves reach 0.75 feet [0.23 metres] long. Two or three stem leaves grow in a whorl. Each divides into three narrow leaflets with toothed or smooth edges. These leaves reach about 0.21 feet [0.064 metres] long.

The basal leaves may emerge as early as January. Flowers follow from late winter into early spring. Short racemes hold the blooms at the stem tips. Each flower has four petals and a star-like outline. White petals often carry a pink-purple tint. Blooms measure up to about 0.08 feet [0.025 metres] across. Slender green pods follow the flowers. The plant produces seed during April and May. Its above-ground growth then dies back, leaving a gap after spring.

Grow slender toothwort in partial or deep shade. It suits soil rich in humus that stays moist. NC State describes a preference for slightly acidic soil. Its soil table also lists neutral conditions. The plant grows fast and needs a medium level of upkeep. Gardeners can raise it from seed or divide established plants. Its small size suits borders and planting in small groups. Native plant gardens and shaded woodland beds also suit it. It can grow beside shaded ponds and streams.

The early flowers provide the plant's main seasonal display. Its low growth also suits small garden spaces. NC State reports no major pest, disease, or other plant problems. The supplied sources give no hardiness-zone range for this species. They also provide no evidence about edible parts or toxicity.