Phlox as a genus is a genus of 68 species of perennial and annual plants in the family Polemoniaceae. They are found mostly in North America (one in Siberia) in diverse habitats from alpine tundra to open woodland and prairie.
Phlox plants can be perennial, annual, or biennial. The perennial varieties, which are the most common in gardens, form clumps that spread over time. They can range in height from low-growing, creeping types suitable for ground cover to upright varieties that can grow up to 4 feet tall. The leaves are lance-shaped to ovate, and they’re arranged in opposite pairs along the stem. The texture can vary from smooth to somewhat hairy.
Phlox flowers are known for their star-shaped, five-petaled blooms which cluster in dense, rounded heads or loose panicles. Colors include a wide spectrum: white, pink, red, purple, blue, and sometimes with a contrasting eye or center. They bloom profusely, with some varieties offering scents that range from sweet to spicy.
Depending on the species, Phlox can bloom from spring through late summer. Perennial garden phlox (Phlox paniculata) typically blooms in mid to late summer. Many Phlox varieties are highly fragrant, attracting pollinators like butterflies, moths, and hummingbirds.
Perennial Phlox species are hardy in USDA zones 3 to 9, making them quite versatile for different climates. Prefers full sun but can tolerate some light shade, especially in warmer climates. Susceptible to powdery mildew, especially in humid conditions.
Phlox Flowers
Garden Phlox (Phlox paniculata)
- Characteristics: This type is known for its tall, upright growth and large, fragrant flower clusters. The blooms range in color from white, pink, red, lavender, to purple.
- Bloom Time: Mid to late summer.
- Height: 2-4 feet.
- Growing Conditions: Prefers full sun and moist, well-drained soil.
- Special Note: Garden phlox is prone to powdery mildew, so good air circulation is important.
Creeping Phlox (Phlox subulata)
- Characteristics: A low-growing, mat-forming variety often used as ground cover. It produces a carpet of star-shaped flowers in shades of pink, purple, white, or blue.
- Bloom Time: Early spring to early summer.
- Height: 4-6 inches.
- Growing Conditions: Thrives in full sun and well-drained, rocky or sandy soil.
- Special Note: It’s drought-tolerant once established and great for rock gardens.
Woodland Phlox (Phlox divaricata)
- Characteristics: This type is also known as wild sweet William. It features delicate, fragrant flowers and is ideal for shaded or woodland gardens. Common colors include pale blue, lavender, and white.
- Bloom Time: Mid to late spring.
- Height: 12-18 inches.
- Growing Conditions: Prefers partial shade and rich, moist soil.
- Special Note: Attracts butterflies and bees.
Moss Phlox (Phlox stolonifera)
- Characteristics: Another type of creeping phlox, it is known for its low, dense foliage and small, fragrant flowers that bloom in clusters. Available in white, pink, and purple.
- Bloom Time: Spring.
- Height: 6-12 inches.
- Growing Conditions: Prefers partial shade and well-drained soil.
- Special Note: Ideal for rock gardens and borders.
Annual Phlox (Phlox drummondii)
- Characteristics: A compact, bushy plant that produces an abundance of brightly colored flowers. Colors include red, pink, purple, yellow, and bicolored varieties.
- Bloom Time: Summer to early fall.
- Height: 6-24 inches.
- Growing Conditions: Full sun and fertile, well-draining soil.
- Special Note: Great for garden beds and containers.
Perennial Phlox (Phlox carolina)
- Characteristics: This type has a more upright growth habit with clusters of pink or white flowers. It’s resistant to powdery mildew.
- Bloom Time: Summer.
- Height: 2-3 feet.
- Growing Conditions: Full sun to partial shade and well-drained, fertile soil.
- Special Note: Low-maintenance and tolerant to a variety of conditions.
Sand Phlox (Phlox bifida)
- Characteristics: A spreading, low-growing plant with deeply cut, star-like petals in shades of white and light lavender.
- Bloom Time: Spring to early summer.
- Height: 4-6 inches.
- Growing Conditions: Full sun and sandy, well-drained soil.
- Special Note: Ideal for xeriscaping and rock gardens.
Downy Phlox (Phlox pilosa)
- Characteristics: Features small, hairy leaves and clustered pink to purple flowers. Known for its natural, wildflower look.
- Bloom Time: Late spring to early summer.
- Height: 1-2 feet.
- Growing Conditions: Full sun to partial shade and dry, well-drained soil.
- Special Note: Attracts pollinators like bees and butterflies.
Alpine Phlox (Phlox condensata)
- Characteristics: A high-altitude variety with dense, cushion-like growth and small, white to pale blue flowers.
- Bloom Time: Late spring to early summer.
- Height: 2-4 inches.
- Growing Conditions: Full sun and well-drained, rocky soil.
- Special Note: Ideal for alpine and rock gardens.
Smooth Phlox (Phlox glaberrima)
- Characteristics: Smooth phlox has narrow, smooth leaves and produces clusters of pink to purple flowers.
- Bloom Time: Late spring to summer.
- Height: 1-3 feet.
- Growing Conditions: Prefers full sun to partial shade and moist, well-drained soil.
- Special Note: Tolerant of wet conditions and good for rain gardens.
Prairie Phlox (Phlox pilosa var. fulgida)
- Characteristics: A variation of downy phlox, this prairie variety has a more intense pink color and is often seen in meadows and prairies.
- Bloom Time: Late spring to early summer.
- Height: 12-18 inches.
- Growing Conditions: Full sun and dry, well-drained soil.
- Special Note: Great for wildflower gardens and native plantings.
Thickleaf Phlox (Phlox amoena)
- Characteristics: A low-maintenance, bushy plant with thicker leaves and vibrant pink or purple flowers.
- Bloom Time: Late spring to early summer.
- Height: 1-2 feet.
- Growing Conditions: Prefers full sun and well-drained soil.
- Special Note: Provides a bright, cheerful display and attracts pollinators.
Rocky Mountain Phlox (Phlox multiflora)
- Characteristics: A hardy, native plant with small, fragrant flowers in shades of white and lavender. It has a clumping habit and thrives in dry conditions.
- Bloom Time: Late spring to early summer.
- Height: 6-12 inches.
- Growing Conditions: Full sun and rocky or sandy, well-drained soil.
- Special Note: Tolerant of drought and harsh conditions, making it ideal for rock gardens.
Blue Phlox (Phlox divaricata ‘Blue Moon’)
- Characteristics: A variety of woodland phlox with deep, rich blue-violet flowers that are fragrant and attract pollinators.
- Bloom Time: Mid to late spring.
- Height: 12-18 inches.
- Growing Conditions: Partial shade and moist, well-drained soil.
- Special Note: Excellent for shaded garden areas and underplanting shrubs.
Drummond Phlox ‘Twinkle Star’ (Phlox drummondii ‘Twinkle Star’)
- Characteristics: A showy, compact annual phlox with star-shaped, bi-colored flowers in shades of red, white, and pink.
- Bloom Time: Summer to early fall.
- Height: 6-12 inches.
- Growing Conditions: Full sun and fertile, well-draining soil.
- Special Note: Works well in containers and borders for a pop of color.
Orange Perfection Phlox (Phlox paniculata ‘Orange Perfection’)
- Characteristics: A striking garden phlox with bright orange-red flowers that form large, conical clusters. This variety is known for its bold, eye-catching color.
- Bloom Time: Mid to late summer.
- Height: 2-3 feet.
- Growing Conditions: Full sun and moist, well-drained soil.
- Special Note: Adds a unique color to traditional phlox gardens.
Candy Stripe Phlox (Phlox subulata ‘Candy Stripe’)
- Characteristics: A type of creeping phlox with white flowers accented by pink stripes, creating a candy-cane effect.
- Bloom Time: Early to mid-spring.
- Height: 4-6 inches.
- Growing Conditions: Full sun and well-drained soil.
- Special Note: Perfect for rock gardens, borders, and as ground cover.
Coral Eye Phlox (Phlox subulata ‘Coral Eye’)
- Characteristics: A vibrant ground cover variety with pale pink flowers and a distinct, darker coral eye at the center.
- Bloom Time: Spring.
- Height: 4-6 inches.
- Growing Conditions: Full sun and sandy, well-drained soil.
- Special Note: Provides a striking contrast in mixed plantings.
David Phlox (Phlox paniculata ‘David’)
- Characteristics: An award-winning garden phlox known for its pure white flowers and strong resistance to powdery mildew.
- Bloom Time: Mid to late summer.
- Height: 3-4 feet.
- Growing Conditions: Full sun and fertile, moist soil.
- Special Note: Ideal for brightening up garden beds and attracting butterflies.
Blue Flame Phlox (Phlox paniculata ‘Blue Flame’)
- Characteristics: Features blue-lavender flowers with a lighter, almost white center. The blooms appear in dense clusters.
- Bloom Time: Mid to late summer.
- Height: 2-3 feet.
- Growing Conditions: Full sun and well-drained, fertile soil.
- Special Note: Its bicolored petals create an eye-catching effect in the garden.
Nicky Phlox (Phlox paniculata ‘Nicky’)
- Characteristics: This variety boasts vibrant magenta-purple flowers with a strong, fragrant scent. The deep color stands out in any garden setting.
- Bloom Time: Summer.
- Height: 3-4 feet.
- Growing Conditions: Full sun and well-drained soil.
- Special Note: Attracts pollinators and resists mildew better than many other varieties.
Sherwood Purple Phlox (Phlox stolonifera ‘Sherwood Purple’)
- Characteristics: A creeping phlox variety with lavender-purple flowers that form a dense mat, perfect for use as ground cover.
- Bloom Time: Spring.
- Height: 6-8 inches.
- Growing Conditions: Partial shade and moist, well-drained soil.
- Special Note: Ideal for shaded slopes or rock gardens.
Laura Phlox (Phlox paniculata ‘Laura’)
- Characteristics: A garden phlox with striking purple flowers and a contrasting white center. It has strong stems that help keep the plant upright.
- Bloom Time: Mid to late summer.
- Height: 3-4 feet.
- Growing Conditions: Full sun and rich, well-drained soil.
- Special Note: Notable for its mildew resistance and vivid color.
Bright Eyes Phlox (Phlox paniculata ‘Bright Eyes’)
- Characteristics: Features soft pink flowers with a darker pink eye, creating a charming, bi-colored effect.
- Bloom Time: Mid to late summer.
- Height: 2-3 feet.
- Growing Conditions: Full sun to partial shade and well-drained, fertile soil.
- Special Note: A popular choice for cottage gardens and attracting butterflies.