Overview
Phlox divaricata 'Blue Moon' is a clump-forming perennial in the genus Phlox, part of the Polemoniaceae family, with deciduous foliage. It typically grows around 0.5 m tall and 0.5 m wide. Phlox divaricata 'Blue Moon' grows best in full sun and full shade, and tolerates sandy and loamy soils and neutral pH. Its UK hardiness is rated H7. Suggested uses include borders, woodland gardens and ground cover. It is native to Ontario.
About
Phlox divaricata, the wild blue phlox, woodland phlox, or wild sweet william, is a species of flowering plant in the family Polemoniaceae, native to forests and fields in eastern North America.
Wikipedia contributors, CC BY-SA 4.0 — Phlox divaricata
About the genus
Phlox is a genus of 68 species of perennial and annual plants in the family Polemoniaceae. They are found mostly in North America in diverse habitats from alpine tundra to open woodland and prairie. Some flower in spring, others in summer and fall.
Wikipedia contributors, "Phlox", CC BY-SA 4.0 — Phlox
Growing conditions
Best soil and position for Phlox
- Sunlight
- Full sun, Full shade
- Soil type
- Sandy, Loamy
- Soil pH
- Neutral
- Soil moisture
- Moist but well-drained
- Aspect
- South-facing
- Exposure
- Sheltered
- UK hardiness
- H7
Plant details
Phlox divaricata 'Blue Moon' size, habit and characteristics
- Plant type
- Perennial
- Habit
- Clump-forming
- Foliage
- Deciduous
- Height
- 0.5 m
- Spread
- 0.5 m
- Suggested uses
- Borders, Woodland gardens, Ground cover
- Native to
- Ontario
- Fragrance
- Lightly fragrant
Care notes
Pruning and caring for Phlox divaricata 'Blue Moon'
- Cultivation
- Prefers partial to full shade, moist, well-drained soil; avoid dry conditions
- Pruning
- Deadhead spent flowers to encourage reblooming; cut back after flowering to maintain shape
- Propagation
- Division in spring or fall; seed propagation possible but less common
- Pest resistance
- Phlox eelworm
- Disease resistance
- Powdery mildew, Grey mould, Leafy gall, Leaf spot
Frequently asked questions
How do I grow Phlox divaricata 'Blue Moon'?
Prefers partial to full shade, moist, well-drained soil; avoid dry conditions.
Where is the best place to plant Phlox divaricata 'Blue Moon'?
Phlox divaricata 'Blue Moon' prefers full sun and full shade. It suits sheltered positions.
What soil does Phlox divaricata 'Blue Moon' need?
Phlox divaricata 'Blue Moon' grows best in sandy and loamy soil. It prefers neutral soil. Aim for soil that stays moist but well-drained.
How do I prune Phlox divaricata 'Blue Moon'?
Deadhead spent flowers to encourage reblooming; cut back after flowering to maintain shape.
How big does Phlox divaricata 'Blue Moon' grow?
Phlox divaricata 'Blue Moon' reaches a height of 0.5 m and a spread of 0.5 m.
Is Phlox divaricata 'Blue Moon' hardy in the UK?
Phlox divaricata 'Blue Moon' has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Phlox divaricata 'Blue Moon'?
Division in spring or fall; seed propagation possible but less common.
From the Fenn Plants journal
- Notes on DaffodilsWhen to plant daffodil bulbs in the UK, how deep, how to naturalise them in grass, why daffodils stop flowering (“blindness”), and why you should never mix cut daffodils with other flowers.
- Keeping Your NerveHow to garden through a heatwave — the best time to water, why deep soaks beat daily sprinkles, caring for pots and vulnerable plants, and why you can let the lawn go brown.
- Made to LastHow to clean, store and protect garden pots and planters — the frost-proof vs frost-resistant difference, winter care for terracotta and ceramic, and how to reuse a broken pot.
More in the Phlox genus
- Phlox 'David'
- Phlox 'Mount Fuji'
- Phlox glaberrimasmooth phlox
- Phlox maculatameadow phlox
- Phlox maculata 'Alpha'meadow phlox 'Alpha'
- Phlox maculata 'Miss Lingard'Meadow Phlox 'Miss Lingard'
- Phlox maculata 'Omega'meadow phlox 'Omega'
- Phlox ovataAllegheny phlox
