English ivy (Hedera helix) is a woody, evergreen vine that covers the ground densely in shade. It also climbs any nearby trees or structures, so control is necessary. Many English ivy cultivars are available with leaves in different shapes, sizes and color combinations. The leaves on the fruiting branches are not the typical lanceolate shape, but oval with no lobes. This vine is quite adaptable, but grows best in rich, humus. It likes to be kept moist, but can succumb to fungus without good air circulation. Varieties include Glacier with gray and green variegation, Conglomerata, a dwarf variety that is slow growing; and Minima with tiny leaves only 1/2 to 1 inch across.
Baltic ivy (H. helix var. baltica) is the most cold hardy of the English ivies, hardy to U.S. Department of Agriculture plant hardiness zone 5. Its leaves are almost indistinguishable from English ivy. A variant, Thorndale, has slightly larger leaves and is hardy to zone 4. It requires the same growing conditions as English ivy.
Algerian ivy (H. canariensis) resembles English ivy except for its distinctive, red leaf stems. Its foliage is slightly shinier than English ivy with five to seven lobes. It is very salt tolerant and prefers moist, rich soil, but adapts to other soil types. Algerian ivy is hardy to zone 6, but is damaged at temperatures below 15 degrees Fahrenheit, making it a desirable ground cover in warmer climates. It grows more rapidly and becomes established more easily in warmer zones than does English Ivy. The cultivar Variegata has yellow leaf edges.
Persian ivy (H. colchica) has the largest leaves of any ivy, growing to 10 inches long and 3 to 7 inches wide and is one of the more cold-hardy species. Varieties include the slightly toothed Dentata, Dentata Variegata, with cream-white, deep-green and gray-green marbled leaves and Sulpher Heart with a streak of gold down the center of each leaf.