Purple Fountain Grass (Pennisetum setaceum ‘Rubrum’) is a popular ornamental grass known for its striking burgundy-red foliage and graceful, arching plumes. While gardeners value its color and texture, those in areas with white-tailed deer populations often worry about browsing damage. Fortunately, Purple Fountain Grass is widely considered a plant that deer generally avoid, making it a practical choice for landscaping success.
How Deer React to Purple Fountain Grass
Purple Fountain Grass is rated as highly resistant to deer browsing by wildlife experts and nurseries. This resistance stems from the physical characteristics of the grass, not a foul taste or toxic compound. Ornamental grasses are generally not a preferred food source because their blades are fibrous and tough, making them difficult for deer to chew and digest compared to softer broadleaf plants.
The primary deterrent is the presence of silica phytoliths within the leaf blades. This mineral compound makes the plant material abrasive, acting like tiny shards that can irritate the mouth and digestive tract of grazers. This tough, gritty texture, combined with the low nutritional value and moisture content of the mature grass, means deer rarely find consuming it worthwhile. Deer typically seek out plants with high moisture and protein content, making the dry, fibrous Purple Fountain Grass a last resort.
Why Deer Resistance Varies
While Purple Fountain Grass is deer-resistant, no plant is completely “deer-proof.” The resistance level can fluctuate significantly based on external factors, as deer are opportunistic feeders influenced by the availability of more palatable food sources.
When natural habitats face environmental stress, such as severe drought or heavy snow cover, preferred food becomes scarce. In these conditions, particularly during late winter and early spring, hungry deer will consume plants they would normally ignore, including fibrous ornamental grasses. High local deer populations also increase feeding pressure, forcing animals to expand their diet to include less desirable plants. Deer may also occasionally nibble on new, softer growth out of curiosity before moving on.
Managing Deer Activity in the Garden
If deer are browsing on your Purple Fountain Grass despite its resistance, a layered approach to management is the most effective strategy. This involves using both chemical deterrents and physical barriers to protect the plants.
Chemical Repellents
Taste and scent-based deterrent sprays can make the plant unappealing. It is important to rotate the type of repellent used to prevent deer from becoming acclimated to a single product. Repellents utilizing putrescent whole egg solids or capsaicin are common options. These should be reapplied regularly, especially after rain, to maintain effectiveness.
Physical Barriers and Environmental Control
Physical barriers offer the most reliable protection, particularly for young or newly planted grasses. A temporary wire cage or mesh netting placed around the plants can block access while they establish themselves. For broader protection, motion-activated sprinklers can startle deer with a sudden burst of water, discouraging them from entering the garden space. Removing other attractants, like fallen fruit, also helps keep the deer moving past your ornamental grasses.