How to Grow the Turtlehead Plant

Look at a turtlehead plant (Chelone spp.), and you know immediately where it gets its name -- from its flowers that closely resemble turtles' heads. Also called codhead, fish- or snake-mouth, or turtle bloom, the flowers surround short spikes. Each flower has two "lips" that open like small mouths when the flower is squeezed. A native perennial in a large part of the eastern United States, turtlehead plants come in several types, all attractive and easy-to-grow choices for a home garden.

Naturally growing in partially shaded, wooded areas, all types of turtlehead plants prefer partial shade, making a spot under tall trees that cast shifting shade ideal. But most species can tolerate full sun, especially when grown in a moist area. The white turtlehead (Chelone glabra), named for its white flowers, is the most sun-tolerant turtlehead species. This plant grows in U.S. Department of Agriculture plant hardiness zones 3 through 8, as does the pink turtlehead (Chelone lyonii). Another variety, called the red turtlehead (Chelone obliqua) because of its blossom color, grows in USDA zones 3 through 9.

If your plant gets some sun during the hot afternoon hours and tends to wilt, set a taller plant or a small shrub on the plant's sunny, west-facing side to provide some shade and help prevent wilting.

The turtlehead plant spreads slowly to form a dense clump, eventually become 1 to 3 feet tall and wide. It does best when given some room to spread, with about 18 to 24 inches between plants.

Naturally growing in bogs or other areas where moisture is ample, this plant thrives when its soil is kept evenly moist, especially when it's still young; once established, a turtlehead can tolerate some dryness, although this might slow its growth. For best results, provide extra water whenever the soil's surface is dry to the touch. Adding about 2 inches of organic mulch under the plant helps retain soil moisture while keeping down weeds, but keep the mulch back from the plant's center to discourage growth of fungus. When the plant's growth slows in fall and it becomes dormant, withhold water and allow the soil to dry out to give the plant a rest.

The turtlehead plant attracts butterflies but might also be eaten by deer.

This plant doesn't require fertilization to thrive, but you can spread an inch of compost under the plant each spring to boost your soil's overall fertility while also improving its ability to hold moisture.

Pinching back stems on a turtlehead early in the growing season helps the plant become bushy and full; use sharp shears, disinfecting the blades by wiping them with rubbing alcohol between each cut to prevent spread of plant diseases.

When planted in a shady spot, turtlehead tends to become leggy and might need to be supported by a stake driven into the ground or a circular wire support. Pinching back a shade-grown plant can produce a stronger, more erect plant and help avoid the need for support.

The turtlehead plant is usually free of any significant pest or disease problems. Slugs or snails might feed on the plant's foliage, especially in wet conditions; control these by hand-picking or using commercial traps.

This plant might develop powdery mildew -- white fluffy deposits on leaves -- or dark spots on leaves from fungal organisms. These are best prevented by watering at the plant's base with a soaker hose or drip irrigation to keep the foliage dry and by spacing plants well apart. It's also helpful to clear away plant debris regularly, because this can harbor fungus.