California fescue is a large, clump-forming bunchgrass native to oak woodlands, chaparral margins, and conifer forests from the Sierra Nevada foothills to the California coast and into southwestern Oregon. It forms arching mounds of blue-green to gray-green foliage with airy seed-bearing culms rising above in spring. One of very few ornamental grasses that performs reliably in dry shade, it occupies a niche that most grasses cannot.
A cool-season grass, it grows most actively in fall and spring and slows significantly in summer heat. It thrives beneath oaks and other canopy trees where summer drought is the norm. Clumps establish best from transplants or fall-sown seed. In late winter, comb out or lightly cut back dead foliage before new growth begins. Divide clumps every five to seven years when the center starts to die out. Low-fertility soil is preferred; excess nitrogen produces floppy, disease-prone growth. Excellent for erosion control on shaded slopes.
The dense clumping habit provides cover and nesting material for ground-nesting birds, and seeds are taken by sparrows and small rodents. Its deep fibrous roots contribute to slope stabilization and improve water infiltration in native plant landscapes.
Red Thread
Pink to red thread-like mycelial strands extend from leaf tips; affected blades turn tan or bleached and patches of grass appear water-soaked before drying to a straw color.
Improve drainage and air circulation around clumps. Avoid overhead irrigation, especially in the evening. Remove and dispose of heavily infected foliage. Apply a fungicide containing thiophanate-methyl or chlorothalonil if infection spreads; do not apply excess nitrogen, which favors the pathogen.
Crown Rot
Lower leaves yellow and wilt; the base of the rosette turns brown and soft, sometimes with white fungal threads at the soil line. Plants collapse in wet conditions.
Remove and destroy affected plants. Improve drainage and avoid overhead watering. Do not mulch directly against the crown. Space plants for airflow and avoid replanting in the same wet spot.
Rust
Orange to brown raised pustules on the undersides of leaves, with yellow spotting on the upper surface. Heavy infections cause leaves to yellow and drop.
Remove and destroy infected leaves. Avoid overhead watering and improve air circulation. Apply a sulfur or copper-based fungicide if it spreads. Clear plant debris in fall.