Grass
Blue Fescue
Festuca glauca 'Elijah Blue' · Poaceae
Also called: Elijah Blue Fescue, Blue Mountain Grass, Gray Fescue, Festuca ovina glauca (former name)
Blue Fescue (Festuca glauca 'Elijah Blue') is a low-water grass well suited to Tucson and the low desert. It's a slow to moderate-growing grass.
Blue Fescue at a glance
- Water use
- Low (established)
- Sun
- In Tucson, morning sun with afternoon shade or bright filtered light; full all-day desert sun will scorch and brown it. A cool-season grass that wants cooler conditions.
- Mature size
- 8-12 in tall and 8-12 in wide (slightly taller in bloom); compact tufted mound
- Growth rate
- Slow to moderate
- Bloom
- Tan to light-blue-green flower spikes aging to buff, Late spring to early summer (flowers are secondary; grown for foliage)
- Cold hardiness
- Cold hardy to about USDA zone 4; cold is not the issue in Tucson. Heat-limited rather than cold-limited here.
- Soil
- Well-draining, even gritty/sandy soil; must avoid wet feet. Tolerates alkaline pH but needs sharp drainage in Tucson.
- Native range
- Species native to Europe (and naturalized across temperate zones); 'Elijah Blue' is a cultivated selection
- Best used as
- Blue-foliage accent and edging, Rock gardens and containers, Mass planting for color contrast, Small-scale xeriscape detail
- Wildlife
- Low wildlife value; deer- and rabbit-resistant.
- Toxicity
- Non-toxic to dogs, cats, and humans. Safe, clumping, non-invasive.
How to grow Blue Fescue in Tucson & the low desert
Watering
Drought tolerant once established but, as a cool-season grass, it dislikes Tucson's summer heat. Water deeply 1-2 times per week in summer (more important here than the species' general drought tolerance suggests) and every 2-3 weeks in cool months. Sharp drainage is critical to prevent crown rot.
Fertilizer & nutrients
Very light feeder. A single light spring application of balanced fertilizer is plenty; lean conditions keep the best blue color. Avoid heavy nitrogen.
Pruning & care
Shear or comb out the clump in late winter/early spring to remove dead blades and refresh the blue mound. Divide every 2-3 years in spring or fall, as centers tend to die out, especially under heat stress.
Notes
The most heat-challenged of these five in Tucson. As a cool-season grass it looks best in fall, winter, and spring and tends to fade, brown, or go semi-dormant in peak summer; plant it in afternoon shade with excellent drainage and treat it as a cooler-microclimate accent. Often grown as a short-lived perennial (replace or divide every few years). 'Elijah Blue' holds color better than some blue fescues but still benefits from shade in the low desert.
Sources: University of Arizona Cooperative Extension / Pima County Master Gardeners; North Carolina Extension Gardener Plant Toolbox; Monrovia; Walters Gardens; Gardenia.net