The Scaevola aemula, commonly known as the Fan Flower, is a popular ornamental plant recognized for its distinctive fan-shaped blossoms and cascading growth habit. Native to Australia, this plant is valued in gardens for its ability to thrive through intense summer heat and its continuous flowering display. For many gardeners, the primary concern when introducing this vibrant plant is whether it will become a food source for local deer populations. This article examines the plant’s palatability and outlines strategies for its protection in environments where deer are a persistent challenge.
Scaevola’s Status as a Deer-Resistant Plant
Scaevola is widely classified by horticultural experts as a highly deer-resistant plant. Deer are selective foragers, and they typically pass over the Fan Flower in favor of more palatable plant species. This designation applies even in areas where the animals are common, as they prefer tender, nutrient-dense foliage that lacks strong defensive characteristics.
The classification of “deer-resistant” is not a guarantee of safety, however; it simply indicates that the plant is not a preferred food source. Deer-resistant is distinct from “deer-proof.” If other food sources become scarce, such as during severe drought or harsh winter conditions, extremely hungry deer may sample or graze on Scaevola, especially new or young growth.
Plant Characteristics That Deter Deer
The unappealing nature of the Fan Flower to deer is due to a combination of physical and chemical defenses. The plant’s stems and leaves possess a slightly coarse or leathery texture, which provides an undesirable mouthfeel that deer tend to reject. These animals often prefer soft, smooth foliage and will avoid plants that feel tough.
More significant is the plant’s chemical composition, which often includes secondary metabolites that taste bitter. These chemical defenses, such as certain alkaloids or polyphenols, are known to activate the bitter taste receptors in a deer’s mouth. This bitterness acts as a natural deterrent, signaling to the animal that the plant is unpalatable, causing them to stop feeding immediately. This biological mechanism is a common evolutionary strategy utilized by many plants to discourage browsing.
Managing Deer in High-Pressure Environments
Even with the Fan Flower’s natural defenses, gardeners in areas with high deer density must take proactive measures. The most effective strategy involves the use of taste and scent-based commercial repellents that make the foliage actively unpleasant. These products often contain ingredients like dried blood, putrescent egg solids, or strong garlic oil, which are harmless to the plant but offensive to the deer’s sensitive sense of smell.
A successful repellent program requires rotation, as deer can quickly become accustomed to a single scent or taste, causing the product to lose its effectiveness. Switching between two or three different repellent formulations every few weeks prevents habituation and maintains a high level of deterrence. For newly planted Scaevola, temporary physical barriers, such as small wire cages or netting, can be placed around the plants until they establish themselves.