Primroses are a part of a large family of flowers growing worldwide called Primula. They have been grown and cultivated for more than 500 years and grow wild along roadways in England. Primroses like cold and moist climates and emerge in early spring. Despite the many varieties, all of them grow a group of leaves at the base of the plant with flowers blooming above the leaves. The leaves on all are egg shaped or oblong, with the narrowest point at the stem.
Candelabra primroses are the larger type of primroses and the easiest to grow. Japanese primroses (Primula japonica) are a candelabra primrose and hardy in the warmer climates to USDA hardiness zone 5. Although Japanese primroses are hardy in warmer climates, they need to be planted in a shaded area. Japanese primroses have a rosette of leaves that encompasses a stalk, which has tiers of flowers. They look like a spoke on a wheel, and the tall flowers of this type reach up to 2 feet. Japanese primroses will multiply by dropping seeds on the ground.
Cowslips, polyanthas and oxlips are members of the vernales primrose family. They are considered meadow plants when growing wild along English roadways. It is an early bloomer and the stems have dozens of yellow flowers with green leaves. It is not as tall as the candelabra, growing up to 6 inches. Vernales primroses drop seeds to multiply. Some hybrids are cultivated from this type, giving hardier and more visually appealing primroses.
Denticulata primroses (Primula denticulata) are unusual in that they may have two to three flowering stems, as they grows older. This type also produces globe-shaped masses of flowers and the stalk, and are only 4 to 8 inches high. A type of primrose in this category is the drumstick primrose, because the leaves resemble the shape of a drumstick. Drumsticks emerge in early spring, and the flower stems sometimes emerge from the plant before the leaves develop.
There are no common names for the kisoana primrose (Primula kisoana). These plants have bright magenta blooms and grow in morning sun, with moist shade. They work well surrounding large trees. Plants send out runners to multiply and can cover a 2-foot-square area. After a couple of years, the kisoana primrose can completely surround a tree.