Lamb’s Ear is a popular perennial valued for its soft, silvery, woolly foliage. The dense hair covering its leaves often makes the plant unappealing to many common garden pests. When gardeners notice holes or discoloration, it signals that an animal, insect, or environmental condition has managed to overcome the plant’s fuzzy texture. Determining the exact source of the damage requires careful observation of the patterns left behind.
Primary Pests Causing Leaf Damage
Slugs and snails are common culprits, leaving behind characteristic irregular holes in the leaves. These pests feed primarily at night and leave a silvery slime trail across the fuzzy leaf surfaces as they move. They thrive in moist, shaded conditions, which can be created by the dense, low-growing nature of Lamb’s Ear itself.
Other small insects target the plant by chewing tissue or sucking sap. Caterpillars, such as cabbage worms, consume leaf material, often leaving larger, ragged holes and small black droppings, known as frass, on the leaves. Sap-sucking insects like aphids cluster on the undersides of leaves, withdrawing plant fluids and leading to distorted new growth and a sticky residue called honeydew. Root weevils are less common, but their adult forms create small, distinctive notches along the edges of the leaves.
Signs of Damage from Larger Animals
Damage from larger mammals is less frequent because the woolly leaf texture is unpalatable. If significant portions of foliage are missing, especially on the outer edges of the plant, a larger animal may be responsible. The pattern of the bite mark helps distinguish between species.
Rabbit feeding is characterized by clean, angled cuts on the stems and leaves, typically occurring close to the ground. Rabbits use sharp incisors to clip vegetation neatly. In contrast, deer lack upper incisors, forcing them to rip and tear foliage, which leaves behind ragged, torn edges on the remaining leaves and stems.
Distinguishing Pest Damage from Environmental Stress
The most frequent cause of decline in Lamb’s Ear is often an environmental stressor rather than a pest. The plant’s dense, velvety hairs trap and hold moisture, making it susceptible to fungal diseases and rot. When leaves appear brown, black, or mushy, especially in the center of the plant or where they touch the soil, it indicates rotting due to poor drainage or overwatering.
Moisture retention makes the plant vulnerable to fungal infections like powdery mildew, which manifests as a white or grayish, powdery coating on the leaf surfaces. Fungal leaf spots may appear as discolored blotches on the foliage, ranging from transparent to brown or black. These issues are prevalent during periods of high humidity and poor air circulation.
Targeted Management and Prevention
Addressing plant decline requires matching the management strategy to the specific cause identified. Since moisture is a primary contributor to rot and slug/snail issues, cultural controls are essential. Improving air circulation by thinning the plant and ensuring excellent soil drainage are effective preventative measures. Mulching the area beneath the leaves with a layer of gravel or grit can help keep the foliage dry and discourage mollusks.
Slugs and snails can be managed through hand removal after dark or the use of slug bait. Aphids can be dislodged with a strong jet of water or treated with insecticidal soap for severe infestations. If the damage is from larger animals, installing low fencing for rabbits or using commercial animal repellents will deter browsing.