How to Grow Deergrass
Muhlenbergia rigens
Deergrass is a tough, drought-tolerant warm-season bunchgrass from the American southwest. Plant in full sun in free-draining soil, spacing plants 90-120 cm apart. It is slow to establish in year one but quickly builds into a graceful arching mound topped by tall slender flower spikes from late summer through autumn. Water occasionally through the first summer; once established it survives on minimal irrigation. Cut back hard to 7-10 cm in late February every one to three years before new growth begins. Avoid rich soils and excess nitrogen — lean conditions keep the plant compact and healthy.
Yearly Lifecycle
Care Essentials
Rarely needed. Deergrass thrives in lean, dry soils. Avoid nitrogen-rich fertilisers which produce floppy growth and reduce drought tolerance.
Watch For
- Aphids on young shoots
- Root rot in poorly drained soils
- Rust in humid conditions
Care Requirements
Light
Full sun
Thrives in full sun. Tolerates light shade but produces fewer flower spikes and looser growth without at least six hours of direct sun daily.
Watering
Drought-tolerant once established
Water regularly in the first season to aid establishment. Once rooted, deergrass needs only occasional deep watering during prolonged dry spells. Overwatering is the most common cause of decline.
Fertilizing
Minimal — avoid nitrogen-rich feeds
Little to no fertiliser needed. Rich soils and nitrogen cause floppy, weak growth. If required, a light top-dressing of compost in spring is sufficient.
Pruning
Cut back to 7-10 cm in late February every 1-3 years
Leave old growth standing through winter for crown protection and visual structure. In late February or early March, cut the whole clump back hard to 7-10 cm before new growth emerges. Cutting is only needed every one to three years, not annually.
Mulching
Light mulch after cutting back in spring
After the late-winter cut-back, apply a thin layer of gravel or coarse compost around the crown to suppress weeds. Avoid burying the crown — good drainage is essential.
