Garden phlox (tall phlox)

Phlox paniculata · Phlox family (Polemoniaceae)

At a glance
Hardiness zones	4 to 8
Sun	full sun to part shade
Water	moderate
Life cycle	perennial
Frost	Hardy: takes frost
Spacing	12 to 36 inches

About Garden phlox (tall phlox)

Garden phlox is an eastern US native with big, fragrant clusters of flowers from midsummer into fall. Hummingbirds, butterflies, moths and bees all visit. Older kinds are known for powdery mildew, so choose one of the many mildew-resistant cultivars that trials have found, like 'Jeana', 'David' or 'Shortwood'.

Native from New York to Iowa and south to Georgia and Arkansas; hardy in zones 4-8.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Grow from divisions or cuttings; named cultivars do not come true from seed. Give plants space and sun so air moves through them, which helps keep powdery mildew down (Penn State; UVM). Divide crowded clumps to open them up (Iowa State).

Soil

Moist, well-drained soil rich in organic matter; it grows in clay or loam (NC State).

Follow a soil test; work 2-3 inches of compost into the top 4-6 inches of soil and aim for pH 6.0-6.5 (Clemson).

Feeding

early spring, before new growth starts: slow-release complete fertilizer such as 12-6-6. Scatter 1-2 lb per 100 sq ft and water it in (Clemson).
about 6 weeks after the spring feeding: slow-release complete fertilizer such as 12-6-6. Repeat the spring rate if you want more growth (Clemson).

Crowded, shaded plants get powdery mildew; give them sun and air (UVM; Penn State).

Harvest

Blooms from July into September. Cut off faded flower clusters to keep blooms coming and to stop self-sown seedlings, which revert to dull pastel colors over time (Penn State).

Varieties (19)

Variety	Type	Notes
Babyface	Mildew-resistant	Pink flowers with a dark eye.
Blue Flame	Mildew-resistant	Light blue flowers on short 12-20 in plants.
Coral Creme Drop ('Ditomdre')	Mildew-resistant	Salmon-pink flowers; about 3 ft tall.
David	Mildew-resistant	White flowers; about 34 in tall.
Delta Snow	Mildew-resistant	White flowers with a purple to soft pink eye; about 4 ft tall.
Dick Weaver	Mildew-resistant	Magenta flowers; about 4 ft tall.
Frosted Elegance	Mildew-resistant	White flowers with pink centers over white-edged (variegated) leaves.
Glamour Girl	Mildew-resistant	Coral-pink flowers; about 3 ft tall.
Goliath	Mildew-resistant	Purple flowers; 26-30 in tall.
Jeana	Mildew-resistant	Fragrant lavender-pink flowers over a long season; about 5 ft tall and 4 ft wide.
John Fanick	Mildew-resistant	Light pink flowers with a darker eye.
Katherine	Mildew-resistant	Lilac-blue flowers with white centers.
Lavelle	Mildew-resistant	White flowers with a pale pink center; about 4 ft tall.
Orange Perfection	Mildew-resistant	Salmon-orange flowers; about 3 ft tall.
Peppermint Twist	Mildew-resistant	Pink and white striped flowers.
Robert Poore	Mildew-resistant	Violet-pink flowers on 5 ft plants.
Shortwood	Mildew-resistant	Rosy pink flowers on 50-54 in stems.
David's Lavender		Lavender flowers.
Lord Clayton		Bright magenta-red flowers.

Pests to watch for

Twospotted spider mite, Four-lined plant bug

Diseases and problems

Powdery mildew, Phytophthora root rot, Black root rot, Cucumber mosaic

In the kitchen

Pets: We found no ASPCA entry for garden phlox, so we can't say it is pet-safe; discourage pets from chewing it.

Sources

Photo: Photo: Frank K., CC BY 2.0, via Wikimedia Commons (CC BY 2.0). Photo resized for the web.

Planting dates and advice are general guidance; check with your local Cooperative Extension office for your area.