Turtlehead

About Turtlehead

Turtleheads are native wildflowers of stream banks, wet woods and marshes, with glossy toothed leaves and tight clusters of hooded flowers shaped like a turtle's head with its mouth open, from late summer into fall (NC State, Wisconsin Extension). White turtlehead grows wild from Newfoundland to Minnesota and south to Georgia and northeast Arkansas; pink turtlehead is from the southern Appalachians, and red turtlehead from the Southeast and central U.S. (Wildflower Center, NC State). Bumblebees, butterflies and hummingbirds visit the flowers, and it is the favorite caterpillar host of the Baltimore checkerspot butterfly (Wildflower Center, Wisconsin Extension).

White and pink turtlehead are hardy in zones 3-8; red turtlehead in zones 5-9 (NC State, Wisconsin Extension). Native to the eastern half of the U.S.; red turtlehead is rare in North Carolina.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Plant nursery-grown plants or divisions in spring, or divide dormant clumps in early spring or late fall and set them about 18 inches apart (Wildflower Center). From seed, sow outdoors in fall or chill moist seed for 6 weeks to 3 months and sow it on the surface, since light helps it sprout; germination can take months and plants take about two years to flower (Wildflower Center, Wisconsin Extension).

Soil

Rich, humus-heavy soil that stays moist to wet; a pond or stream edge, rain garden or low spot suits it, and mulch helps hold moisture (NC State, Wisconsin Extension).

Mix plenty of compost or other organic matter into the bed; turtlehead wants fertile, humus-rich soil that stays moist (NC State, Wisconsin Extension).

Feeding

• Early spring, before new growth, only if a soil test shows a need: compost, or a complete slow-release fertilizer such as 12-6-6. Top-dress with compost each spring, or without a soil test use about 1-2 lb of 12-6-6 per 100 sq ft (Clemson), kept off the leaves and watered in.

Don't let the soil dry out: dry soil invites powdery mildew. Too much shade makes it tall and floppy (NC State).

Harvest

Flowers open from the bottom of each spike upward from midsummer or late summer into fall, roughly July to October (NC State). Pinch stems in spring for shorter, bushier plants, and leave the seed pods to brown if you want seed (Wisconsin Extension).

Varieties (6)

Extension sources document 6 cultivars across the three species.

Good neighbors

Shasta daisy

Wisconsin Extension suggests pairing it with Shasta daisy 'Becky' or monkshood for a late show; this is a design pairing, not a pest-control one.

Diseases and problems

Powdery mildew

In the kitchen

Safety: None of the sources we checked report it as poisonous, but it is not a food plant. Its old use as a bitter tonic and worm medicine is history only (King's American Dispensatory, USDA Forest Service); don't use it as a remedy.

Pets: Not listed by the ASPCA.