Unlike evergreens, deciduous plants do not keep their leaves year round. Instead, they sprout their leaves in the early spring and lose them in the fall when the weather gets cold. Semi-evergreens can exhibit the characteristics of either evergreen or deciduous plants, depending on where they are planted and how severe the winter weather is.
There are two kinds of evergreens. Narrow-leafed evergreens have needle-shaped leaves, while broad-leafed evergreens display leaves of other shapes and sizes. White pines are an example of narrow-leafed evergreens. Rhododendrons and azaleas are broad-leafed evergreens. Although evergreens have leaves on their branches year-round, they shed old leaves periodically. Many semi-evergreen plants are of the broad-leafed variety.
Whether or not a semi-evergreen plant keeps its leaves depends partially on the climate. The National Gardening Association divides the United States into 11 different hardiness zones, which is determined by temperature. Each zone is approximately 10 degrees warmer (or cooler) than the zone next to it. Detailed descriptions in plant catalogs or on websites instruct on how to care for semi-evergreens in different hardiness zones.
Semi-evergreen plants include bushes, flowers, shrubs and grasses. The National Gardening Associations lists bamboo, holly, camellia, rhododendron and feather reed grass as examples of semi-evergreen plants. When planting, gardeners need to know which hardiness zone they are in to predict how these plants will perform. In some zones a semi-evergreen will keep its leaves year-round, and in other zones it will lose its leaves in the winter.