Cotton Candy Grass (Muhlenbergia capillaris) is an ornamental grass known for its unique aesthetic. Also called Pink Muhly Grass, Gulf Muhly, or Hairgrass, its most striking feature is the development of ethereal, airy plumes of pink or pinkish-purple flowers. These plumes resemble delicate cotton candy floating above its foliage, appearing in late summer and continuing through fall.
Planting Cotton Candy Grass
Plant cotton candy grass in spring after the last frost or in early fall. Choose a location that receives full sun for optimal growth and flowering.
When planting, dig a hole twice as wide as the root ball and of similar depth. Loosen the roots, then place the plant so the crown rests at or slightly above the soil surface. Backfill the hole, firming the soil to remove air pockets, and water thoroughly. If planting multiple grasses, space them 2 to 3 feet apart for mature spread and air circulation.
Essential Care Practices
Light Needs
Cotton candy grass thrives in full sun, needing at least six hours of direct sunlight daily for optimal growth and vibrant blooms. While it tolerates some partial shade, insufficient light can reduce flowering and cause leggy growth.
Watering
Once established, cotton candy grass is drought-tolerant and requires minimal supplemental watering. During the initial establishment period, consistent moisture aids root development. Water deeply when the top few inches of soil are dry. Avoid overwatering, as saturated conditions can lead to root rot.
Soil Preferences
Cotton candy grass adapts to various soil types, but well-draining conditions are essential. It performs well in sandy, loamy, or clay soils, tolerating poor soil quality. The plant prefers a soil pH from slightly acidic to neutral. Ensure the site does not have standing water to prevent root rot.
Seasonal Maintenance
Fertilizing
Cotton candy grass is a low-nutrient plant and does not require frequent fertilization. Over-fertilizing can lead to excessive leafy growth at the expense of blooms. If the soil is poor or the plant shows signs of stunted growth, a light application of balanced, slow-release fertilizer in early spring can provide a boost.
Pruning
Prune cotton candy grass in late winter or early spring, before new growth emerges. Cut back the previous season’s foliage to 4 to 6 inches from the ground. This encourages fresh, healthy growth and maintains the plant’s mounding form. Avoid pruning in mid-to-late summer to ensure the development of its flower plumes.
Winter Care
Cotton candy grass is a hardy perennial that goes dormant in winter, its foliage turning tan or brown. Minimal special care is needed beyond late winter or early spring pruning. Leaving dried flower plumes and foliage through winter offers visual interest and some insulation. This grass is tolerant of cold temperatures, hardy in USDA Zones 6 through 10.
Common Issues and Solutions
Cotton candy grass is resistant to pests and diseases, but some issues can arise. A lack of flowering is often attributed to insufficient sunlight or excessive fertilization; ensure the plant receives at least six hours of direct sun daily and avoid heavy fertilizer applications. Poor growth can stem from inadequate drainage or overly wet soil conditions, which may lead to root rot; this grass prefers well-draining soil and is drought-tolerant once established, so excessive watering should be avoided. Fungal diseases like tar spot or rust may appear in humid conditions or if air circulation is poor; providing adequate spacing between plants can improve air circulation and help prevent such issues.