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Border phlox

Botanical name: Phlox

Common name: Perennial phlox

Border phlox are a popular choice for cottage-style gardens and romantic herbaceous borders. As cultivars of Phlox paniculata, P. maculata and P. × arendsii, their sturdy upright stems carry domed or pyramidal flowerheads in summer. They mix well with other summer-flowering perennial plants such as delphiniums, astrantias and campanulas.


At around 1-1.5m (3¼-5ft) tall, clumps of phlox offer flowers through the spectrum of delicate lavender and baby-pink pastels to bright shades of orange and cerise. Some cultivars have variegated or dark foliage. In bloom, they have a spicy, dry scent.


Border phlox need fertile, free-draining soil in sun or light shade. They appreciate applications of garden compost or well-rotted manure to improve the soil and retain moisture.


Performance can be disappointing on poor, dry soils, so it's well-worth improving these before planting.

Did you know?

Trimming back the faded flowered stems, or snipping out the central part of each phlox flowerhead, often results in further flowers growing out from side shoots into autumn.

Growing guide

Border phlox we recommend

Useful advice

Perennials: cutting back

Perennials: cutting back

Perennials: dividing

Perennials: dividing

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