Primula (polyanthus type)

Common Name: polyanthus 
Type: Herbaceous perennial
Family: Primulaceae
Zone: 5 to 7
Height: 0.50 to 1.00 feet
Spread: 0.50 to 7.50 feet
Bloom Time: Seasonal bloomer
Bloom Description: Most colors except green
Sun: Part shade to full shade
Water: Medium
Maintenance: Medium
Suggested Use: Annual, Ground Cover
Flower: Showy
Tolerate: Rabbit

Culture

Primroses provide you with early spring blooms in almost every color of the rainbow. They prefer cool temperatures, a rich humus soil (lots of compost and leaf mold) and partial shade. They appreciate full sun in the spring, but must have semi-shade as the temperatures warm. They are quite tolerant of being transplanted, even when they are in bloom. They should be planted in a cool, partly shady area in the garden with rich, well-draining, slightly acid soil (pH 6.5). Primroses need to be planted so that their crown is right at soil level and at least six inches apart.

Primroses may be grown indoors if you are able to provide them with cool night temperatures of 50-60° F, high humidity, filtered sun and moist soil. Daytime temperatures must remain below 80° F. These are thirsty plants and they like having cool roots. To prolong indoor blooming, primroses should be kept in a cool environment. Another way to prolong bloom is to give regular doses of half-strength fertilizer solution. When they have finished blooming in the house it is best to plant them directly into the garden, or summer them outdoors in their pots and move back to the house at the end of the summer.

Noteworthy Characteristics

Polyanthus primroses are a naturally occurring hybrid between Primula veris and P. vulgaris. Both species are native to Europe and have overlapping ranges. These hybrids have been cultivated by humans for centuries and are available in a large variety of colors. Other species have been introduced into hybrid lineages and the parentage of most cultivars is not fully known. The foliage of polyanthus primroses is dark green, hairy, and deeply textured. Clusters of 4-12 flowers are held on stout stalks above the foliage in spring. Occasionally given the hybrid name P. × polyantha.

The genus name Primula means "little earliest one" and is the feminine diminutive of the Latin primus.

The common name polyanthus and the hybrid name polyantha both mean "many flowered" in reference to the floriferous nature of these hybrid primroses.

Problems

Watch for aphids, mealybugs, mites and whiteflies. Excessive fertilizer buildup in soil can also be a problem. Plants do not like to be potbound.

Garden Uses

Primulas are a delightful indoor plant, a true harbinger of spring. They also will grow in the garden, but will not thrive in the heat of summer.