Common Name: garden phlox
Type: Herbaceous perennial
Zone: 4 to 8
Height: 2.00 to 2.50 feet
Spread: 1.50 to 2.00 feet
Bloom Time: July to September
Bloom Description: Lilac blue with white central star
Sun: Full sun to part shade
Flower: Showy, Fragrant
Attracts: Birds, Hummingbirds, Butterflies
Tolerate: Deer, Clay Soil, Black Walnut
Grow in moderately fertile, medium moisture, well-drained soil in full sun to light shade. Best in full sun. Prefers rich, moist, organic soils. Needs good air circulation (space well and thin out stems as needed) to help combat potential powdery mildew problems. Intolerant of drought and needs to be watered in dry spells. Avoid overhead watering however. Appreciates a summer mulch which helps keep the root zone cool. Remove faded flower panicles to prolong bloom period and to prevent unwanted self-seeding (cultivars generally do not come true from seed).
'Katherine' is a garden phlox cultivar which typically grows in an upright clump to 2-2.5' tall. Fragrant, tubular flowers (1/2" to 1" diameter) with long corolla tubes and five flat petal-like lobes are lilac blue with white central stars. Individual flowers are densely arranged in large, terminal, pyramidal clusters (panicles to 6-9" long) atop stiff, upright stems which seldom need staking. Long mid to late summer bloom sometimes extends into early fall. Narrow, opposite, pointed, lance-shaped leaves (to 5" long). Good fresh cut flower. The name Phlox is derived from the Greek word for flame.
Phlox is not always an easy plant to grow well. Powdery mildew and root rot can be serious problems. Spider mites and plant bugs can also be a problem, particularly in hot, dry conditions.
Garden phlox is a staple of the perennial border. Mixes well with other perennials and provides long summer bloom. Regardless of flower color, garden phlox is attractive to hummingbirds and is a good selection for inclusion in a bird garden.