Primroses are a highly popular bedding plant. The blossoms of the plant, which can reach 2 inches in diameter, are grouped in the centre of the primrose and surrounded by dark green leaves. There are more than 400 species of the primrose (Primula) and in temperate climates they will winter over and bloom again each spring. Beloved for their vibrant and colourful early spring blooms, primroses will flower all summer long with proper care.
Plant your primroses in early spring. Choose a location that is partially shaded if you live in a climate that has hot summers, as primroses thrive in cooler temperatures. If you live in a cooler climate, you can place the plants in full sun.
Make sure the soil is well-draining but does not gather standing water, as this will cause the plants' roots to quickly rot. Primroses thrive in soil that has high organic content, so mix an organic compost or peat moss into the soil before you plant the flowers. Loosen the young plants from their temporary containers, and plant them in holes that are only as deep as the root balls. They should be 6 inches apart at the minimum. Surround the plants with mulch as this will help them retain moisture, and water deeply immediately after planting. Continue to water enough to keep the soil moist.
Remove spent blooms immediately and frequently. This is called "dead heading" and will encourage new flowers to grow. If you do this on a consistent basis, the primroses will continue to bloom all summer long. In addition, remove any leaves that begin to discolour.
Water primroses frequently, as they need moist soil, and especially if the weather is hot. Move container primroses to shadier areas during the hottest weeks of the summer.
Fall and Winter Care
Once the primroses have stopped blooming, mound the mulch around them to protect them from winter freezing. Although they can tolerate winter freezes, the mulch will help them overwinter better. Container primroses can be brought inside and treated as houseplants until the spring. Primroses grown indoors should be kept near a sunny window and exposed to temperatures in the 70s F. during the day and in the mid-50s at night.