Culture & Growth: Epimediums are easy to grow, long-lived shade perennials that thrive in well-drained, moisture retentive soils. Although many grow on limestone in China, they also have grown very well here in the acid soils of New England.
They can be planted in partial sun in northern latitudes; needing more shade further south. Too much sun will scorch the leaves. They are tough, and once established, most tolerate dry shady garden sites where other plants fail, making them good choices for planting under shallow-rooted trees and in gardens that experience periodic drought. Epimediums grow by underground woody rhizomes, and do not tolerate poor drainage. The length of their annual rhizome growth determines whether they will colonize an area, or remain in a clump. In the description we list the typical annual rhizome growth under optimal conditions in our climate (central Massachusetts). Growth varies in different parts of the country, depending on conditions and length of season. Although some spread, they are not invasive. They are also not favored by deer. Heights range from 6” to 2.5’, but are most commonly from 12″ to 18″. Clump forming types usually mature to a plant that is as wide as it is tall. Use this general rule to help you with spacing the plants out in your garden when planting.
Hardiness: Unless otherwise stated in their descriptions, ALL plants offered here have thrived in our nursery (USDA Zone 5b), although we usually have snow cover. Many of these species/varieties are new to cultivation and have not been tested as to their environmental limits elsewhere. Customers in extreme weather areas often ask for suggestions as to which Epimediums will grow in their climate. For those gardening in USDA Zones 8 & 9, we suggest you first try plants categorized as heat-tolerant as they are native to warmer regions of the world. Heat tolerance is not the only issue for growing epimediums in warm climates. Many of them also need a minimum period of cold dormancy in winter to initiate bloom. Those in Zones 3 & 4 are advised to start with plants categorized as cold-tolerant. On the Home Page, click on Find Plants, then click on Growth & Habit to see selections that are especially heat or cold tolerant.
Epimediums do not tolerate rapid freezing and thawing, especially if their rhizomes are exposed. This is especially important when using them in trough plantings. We recommend at least a few inches of mulch in the garden, and caution against holding the plants in pots over winter—it is very risky!