Stachys byzantina, commonly known as Lamb’s Ear, is a perennial cherished for its soft, silvery foliage that adds unique texture to a garden. The plant is hardy, thriving across USDA hardiness zones 4 through 8, and is known for its drought tolerance. However, this perennial’s greatest vulnerability is not the cold winter temperatures, which it tolerates well, but rather the wet conditions of winter and early spring. The dense, fuzzy hairs covering its leaves trap moisture, leading to crown rot and various fungal diseases when combined with sustained cold. Specific care focused on minimizing moisture exposure is necessary to ensure the plant successfully overwinters.
Late Fall Preparation Steps
Preparing the plant in late autumn is a preventative measure focused on improving air circulation and removing potential sources of disease. The dense, low-growing mat of foliage can easily harbor moisture and debris as temperatures drop. Before the ground freezes or heavy winter precipitation begins, clear the area around the plants.
Carefully remove any dead, yellowing, or decaying foliage that has fallen onto or is pressed against the soil surface. This cleanup is important because old, damp leaves can become a breeding ground for pathogens that cause rot and fungal infections. A light pruning of overgrown sections can also be performed to open up the plant’s center, further increasing airflow to the crown. Use clean shears for any cutting, focusing on removing any stems or leaves that look overly tattered or mushy.
Managing Moisture and Drainage
The plant’s distinctive soft, woolly leaves make it susceptible to winter rot. The dense pubescence acts like a sponge, holding water from rain and snow, which then encourages the growth of fungal organisms near the plant’s base. Poor drainage is the single largest cause of winter loss for Stachys byzantina.
The best defense is ensuring the plant is established in soil that drains rapidly, preventing water from pooling around the crown for extended periods. If your garden soil is heavy clay, amending the planting site with coarse sand, grit, or organic matter like compost can significantly improve soil texture and water percolation. Planting Lamb’s Ear on a slight slope or in a raised bed naturally assists with drainage, directing excess water away from the plant’s root zone. Once the plant enters its winter dormancy period, supplemental watering should cease entirely, as the plant is drought-tolerant and requires minimal moisture.
Insulating Against Extreme Temperatures
While moisture is the main threat, physical protection becomes necessary in the coldest regions, typically USDA zones 4 and 5, where temperatures can drop below 15°F. The goal of insulation is to stabilize the soil temperature and shield the foliage from harsh winter winds. A thin layer of organic mulch, such as shredded leaves or pine boughs, can be applied to the soil after the ground has frozen.
It is important to apply any insulating material loosely, maintaining distance around the plant’s central crown. Covering the crown can trap humidity, negating efforts to prevent rot and potentially suffocating the plant. In areas with minimal snow cover or prolonged extreme cold, a lightweight horticultural fabric or burlap cover draped over the plants may offer additional windburn protection, but this should be removed during warmer spells to allow for air circulation.
Springtime Recovery and Cleanup
As the weather begins to warm in early spring, the Lamb’s Ear patch may appear tattered, with some leaves looking brown, mushy, or flattened from the winter conditions. This appearance is normal, as the plant often experiences dieback in colder climates, but it is resilient and will send up new growth from the crown. The first task is to remove any heavy winter mulch that was applied to the ground to prevent the plant from becoming excessively damp as the snow melts.
Next, perform the cleanup by carefully removing all the dead or damaged foliage. You can easily pull away dead leaves by hand, or you can use a light leaf rake to gently “comb” through the patch, removing debris without disturbing the growing crowns. Cutting back severely damaged foliage down to the crown encourages the emergence of fresh, silvery leaves. Once this cleaning is complete, a light application of compost can be spread around the base to provide a nutrient boost for the season’s new growth.