Moss roses (Portulaca grandiflora) are popular annuals cherished for their vibrant, cup-shaped flowers and ability to thrive in hot, dry conditions. This low-growing, semi-succulent plant is a common feature in garden beds and containers. Gardeners often wonder if these colorful plants are safe from local wildlife, particularly rabbits, which are notorious for sampling vegetation. Understanding this interaction requires looking at the animals’ foraging behavior and the plant’s chemical makeup.
The Rabbit’s Diet and Moss Rose Appeal
Rabbits are herbivores whose diet primarily consists of grasses, broad-leaf weeds, and tender new growth. They seek out plants that are readily available and easy to consume, especially those with soft textures and high water content. Rabbits are drawn to young annuals and seedlings because their tissues are soft and rich in moisture.
Moss rose fits this profile due to its semi-succulent nature; its fleshy stems and leaves store water, making the plant appealing to rabbits, especially in dry weather. While not a preferred staple like clover, horticultural experts frequently list moss rose as an annual that is “moderately to severely damaged” by rabbits. When palatable food sources are scarce, or the rabbit population is high, they will readily consume the moss rose.
Safety and Toxicity Concerns
The primary concern regarding the safety of moss roses for rabbits centers on the presence of oxalates, compounds found naturally in the Portulaca genus. Moss rose contains soluble oxalates, which can be absorbed into the bloodstream. There, they bind with calcium, potentially leading to hypocalcemia.
Excessive consumption of oxalate-rich plants can also lead to the formation of calcium oxalate crystals, which may be deposited in the kidneys. While the plant is sometimes listed as non-toxic, this classification often assumes the rabbit consumes only a small quantity. Rabbits are highly susceptible to urinary tract issues and stone formation, making the chronic intake of high-oxalate plants a risk. Ingestion in quantity can cause digestive upset, and prolonged consumption may contribute to serious kidney damage.
Identifying and Preventing Rabbit Damage
Identifying rabbit damage on moss roses is straightforward due to the animal’s unique feeding pattern. Rabbits possess sharp incisors that leave a clean, angled cut on stems, typically at a 45-degree angle. This damage is concentrated low to the ground, usually within the first foot of the plant’s height. Damage from rabbits can be distinguished from deer browsing, which leaves a ragged, torn edge on stems because deer lack upper incisors. Finding small, round droppings scattered near the damaged plants is another sign of rabbit presence. This damage requires mitigation to protect the moss roses.
Effective prevention relies on physical exclusion, as no plant is completely rabbit-proof. Deterrents must be reapplied frequently.
Physical Barriers
Constructing a small fence around the garden bed using chicken wire or hardware cloth with a mesh size of 1 inch or less is the most reliable strategy. The barrier should be at least two feet high and buried six to twelve inches into the ground to prevent rabbits from burrowing underneath.
Cultural and Chemical Controls
Taste-based repellents containing capsaicin or sulfur compounds can be applied directly to the foliage to make the moss rose unappealing. These deterrents must be reapplied after rain or watering. Cultural controls also help, such as removing nearby brush piles or tall grass that rabbits use for shelter and nesting. Planting companion plants that rabbits dislike, such as those with strong scents like marigolds or alliums, can help create a protective perimeter.