Scutellaria ovata aka Heart Leaf Skullcap

Scutellaria ovata is a perennial in the mint family. Its common name is heart-leaved skullcap. It grows wild across the central and eastern United States. Its range extends south into northeastern Mexico. In Missouri, it grows in open woods and rocky glades. It also grows on ledges and steep bluff slopes. Plants vary in their traits across this wide range.

Garden plants often stand about 1.3–2 feet [0.4–0.61 metres] tall. Some reach 3 feet [0.91 metres], according to NC State. They spread to about 1.5 feet [0.46 metres] wide. The stems stand upright and have a square cross-section. Fine, pale hairs cover the green stems. The stems have no scent. Pairs of simple green leaves grow opposite each other. Each leaf has a heart-shaped base and a wrinkled surface. The edges have rounded teeth or sharper teeth. Leaves reach about 0.33 feet [0.10 metres] long. Their undersides are paler, with a variable coat of hairs. Hairs also grow on the leaf stalks.

The flowers form branched racemes at the stem tips. These clusters can reach 0.5 feet [0.15 metres] long. Each bloom forms a tube with two lips. The upper lip arches like a hood. The lower lip bears a white patch. Flower colour ranges from lavender to blue-purple. NC State reports bloom from May through July. Missouri Botanical Garden gives a longer season, through September. Bees and moths visit the plants. Brown capsules follow the flowers from June through September. Each capsule holds nutlets within two joined sections. The top drops away to release the seeds. The cup-shaped lower section stays on the stem.

Grow this plant in full sun or part sun. It suits well-drained soil with dry to moderate moisture. It tolerates drought and shallow, rocky ground. NC State also lists sandy soil, loam, and acid soil. The plant grows at a moderate rate and needs little upkeep. Its listed hardiness range is USDA zones 4–8. Underground rhizomes help it spread, and seedlings may appear nearby. Grow new plants from seed or divide existing clumps. Hot, dry summer weather can trigger dormancy after flowering.

Use it in borders, meadows, and gardens of native plants. It also suits cottage gardens and open woodland areas. Its blooms add colour and draw insects to pollinator gardens. Deer and rabbits tend to avoid its bitter leaves. Neither main garden source reports major pest or disease trouble. Powdery mildew and leaf spot can still occur. Aphids are another pest to watch for.