Garden phlox is an erect herbaceous perennial that may grow 2 to 4 feet tall and is clump-forming. Flowers come in various colors and bloom mid-summer to mid-fall. It mixes well with other perennials, attracts hummingbirds, and is a good selection for a bird garden. This popular flower has escaped gardens and naturalized into areas beyond its original native range. Garden phlox prefers sun to partial shade and moist, fertile, and well-drained soils. Good air circulation (adequate spacing and thinning of stems as needed) will help combat powdery mildew. Overhead watering should be avoided. Phlox needs to be watered in dry summers and mulched to keep the root zone cool. Removing faded flower panicles will prolong blooming and prevent self-seeding as cultivars do not come true from seed. In winter, plants should be cut to the ground and removed from the garden to minimize possible powdery mildew infection for the following season. Taller stems may need staking. The cultivar 'Jeana' was selected as the 2024 Perennial Plant of the Year® by the Perennial Plant Association for its floriferous habit and pollinator-friendliness. Insects, Diseases, and Other Plant Problems: This plant has numerous pest and disease problems and is not always an easy plant to grow well. Phlox bugs, powdery mildew, and root rot can be serious problems. Spider mites can also be a problem, particularly in hot, dry conditions. More information on Phlox .
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt)
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 4 ft. 0 in. | Width: 2 ft. 0 in. - 3 ft. 0 in.
Growth rate
Medium
Maintenance
Medium
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Erect; Multi-stemmed; Pyramidal
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Elliptical; Lanceolate; Ovate
Leaf margin
Entire
Leaf feel
Smooth
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
Deep green leaves are 4-6 inches long with conspicuous veins and are opposite, acute, cuneate, simple, pointed. The leaves are ovate to elliptic to lanceolate. The veins branch off the center vein then curve toward the tip of the leaf near the edge and connect with the next vein, forming what appears to be a vein along the edge of the leaf. Upper leaves are subsessile to clasping.
Flower color
Blue; Pink; Purple/Lavender; Red/Burgundy; Variegated; White
Flower value
Fragrant; Good Cut; Long Bloom Season; Showy
Flower form
Panicle
Flower shape
Tubular
Flower size
< 1 inch
Flower detail
Garden phlox has fragrant, tubular, pink-purple, blue to lavender to purple to white florets (to 3/4” diameter) that are densely packed in large, tiered, domed terminal clusters (to 6-8"). Florets have a long corolla tube and five flat petal-like lobes. The calyx is tubular, ribbed, with 5 lobes, and is subulate. The corolla is salverform and 5-lobed. Flowers bloom from July to August.
Bloom time
Summer
Stem detail
Stems are stiff and erect.
Wildlife & Ecology
Native status
Native
Origin
Eastern United States
Distribution
New York to Iowa south to Georgia, Mississippi, and Arkansas.
Phlox Plant Bug and Other Lopidea Plant Bugs; Fourlined Plant Bug; Oriental Beetle
Disease problems
Phytophthora Root and Crown Rot in the Landscape; Black Root Rot on Ornamental Plants; Phytophthora Blight and Root Rot on Annuals and Herbaceous Perennials