South Dakota Native Plant Research
Polemoniaceae : Phlox pilosa

Polemoniaceae : Phlox pilosa


Download Seed: The black seed of phlox is 1.5-2 mm long. (34 KB)

Download Seedling:Three month old phlox seedling growing in research greenhouse at SDSU. (449 KB)

Download Vegetative: The leaves can be up to 4 inches long. (85 KB)

Download Flowering: Flowers are found at the top of the stems in rounded clusters. (824 KB)

Download Flowers and flower buds (486 KB)

Download Fruiting: The fruiting is a capsule. (992 KB)

Family Name


Common Name

Prairie phlox, Downy phlox


Phlox pilosa is a perennial herb from a stout rootstock, with I-several branching stems with 6-12 nodes, growing 20-75 cm tall, covered with simple and/or glandular hairs. The simple, alternate, sessile leaves are narrowly lance-linear, 30-100 mm long, 3-30 mm wide and hairy, especially along the entire margins and the midvein. The inflorescence is a panicle with up to 100 flowers with pedicels usually les than 10 mm long and covered with glandular hairs. The calyx is 8-15 mm long, the tube and 5 lobes about equal in length and covered with glandular hairs. The white, pink or purple corollas have a tube 8-16 mm long with 5 reflexed oblanceolate to obovate lobes 10-12 mm long and 6-8 mm wide. The style is 3-lobed and 1-3 mm long. the fruit is an ovoid capsule. Prairie phlox blooms from May into July in open woods and meadows in eastern South Dakota.

Additional Notes

Prairie phlox is beautiful when in bloom, with large clusters of flowers that can have an assortment of colors, and that attract many different butterfly pollinators. They are fairly easy to grow and can be quite tall and robust in good soil with full sun. Starting them in a greenhouse will improve seed germination success.

Horticulture Notes

Seed collection: Collect brown capsules in July and August and allow them to dry in a paper bag.

Germination: Seeds need a 60-day cold moist treatment for spring planting or do well with fall sowing.

Vegetative propagation: In good locations the plants spread by short rhizomes and can be propagated by separation new plants.

Light: Full sun to partial shade.

Soil: Rich loams, clay loams, sandy loams and some rocky soils.

Water: Medium wet to medium dry.

Polemoniaceae : Phlox pilosa