Garden Phlox [Phlox Paniculata] Growing And Care

Phlox Paniculata [Floks, pan-ick-yoo-LAY-tuh] belongs to the Polemoniaceae family and is a native plant to central and eastern America, as well as eastern Canada.

It’s found in thickets, rich low woods, and streams. This plant is cultivated extensively as an ornamental plant in various lands.

Blooming Garden Phlox [Phlox Paniculata] Pin

It is among the rare perennials which come in almost every shade on the color wheel.

The color options are so wide; it gets difficult to make the selection.

The common names of this plant include:

Phlox Paniculata Care

Size & Growth

This herbaceous perennial grows in clumps to about 2” – 4” inches tall, and 2” – 3” inches wide.

The stems are clothed with deep green, elliptic, pointed, opposite, and veined leaves which sometimes require staking.

These leaves are 4” – 6” inches long.

These leaves are shaped like a lance head.

Their veins start from the center vein and branches out in a curve to the leaf’s tip.

Majority of phlox have green-colored leaves, but some have variegated foliage with yellow or creamy white margins.

Flowering and Fragrance

Phlox Paniculata produces five-petal florets of fragrant flowers along corolla tubes which are packed in dozens of panicles or terminal clusters with green leaves.

These are in different sizes, typically from 4” – 6” inches tall and 6” – 8” inches wide.

The fragrance of the flowers is mostly sweet.

The flowers look stunning when planted in contrasting colors.

The flower colors come in different shades depending on the variety including:

  • Pink Flowers
  • Magenta
  • White Flowers
  • Bright Pink
  • Lavender-pink

It has a long blooming season throughout the summer until early fall.

Light & Temperature

Summer Phlox grow optimally in full sun to partial shade.

The flowers of this plant flourish the best in full sun.

It is best to provide it with a minimum of six hours of sun every day.

The preferred temperatures for this plant are between 68° – 74° degrees Fahrenheit (20° C – 23° C).

United States hardiness zone 4 – 8 (USDA).

Watering and Feeding

This plant dislikes drought and likes to be watered in dry conditions.

It is best to water this plant when the foliage starts wilting.

Phlox must get around an inch of water every week, especially in the growing season, which will help in keeping the foliage healthy.

Avoid watering from overhead, and aim for the root zone instead.

Soil & Transplanting

Phlox Paniculata prefers to grow in well-drained, fertile, and moist soil which is rich in organic matter, like compost.

The soil should be slightly alkaline.

The plant benefits from regular lime applications if the soil is too acidic.

Grooming and Maintenance

This plant doesn’t need pruning in normal circumstances.

However, if there is a need to delay the bloom period, and if bushier foliage is required, cut back or pinch the stems back between one-third and one-half during the early summer.

Spend time deadheading spent flowers to extend the bloom time, which will also reduce the amount of unwanted reseeding.

When the plant experiences its first frost, it is ideal to cut the stems back just around the soil line and eliminate the foliage.

This should be done if the plant has powdery mildew.

The roots should be protected during the harsh cold by adding a mulch layer before the ground starts to freeze.

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How to Propagate Summer Phlox

The easiest way of propagating the garden phlox is through divisions.

Dig the plants up during the early spring or late summer.

Create sections of the clumps by separating them, using a sharp knife.

It is best to immediately replant the divisions.

All of the divisions must include a minimum of three shoots, along with a small portion of the root.

Propagation of this plant is also done through stem cutting, which should be done during the early summer.

Paniculata Phlox Pest or Diseases

The major issue for the Phlox plant is the powdery mildew fungus which attacks the leaves of this plant and causing them to turn gray and become shriveled.

This disease problem is most common during high humidity in muggy hot summer days.

Spider mites are a problem in hot, dry conditions.

The plants placed under partial shade are also vulnerable to experience powdery mildew.

This issue is prevented by good air circulation by selectively thinning the stems of this plant to give it sufficient spacing and planting mildew-resistant cultivars.

While thinning the plant during the early spring, it is best to leave behind four to five strong stems.

Garden Phlox Uses

Due to its wide variety of colors, it is popularly used in gardens. Planting even two to three species of phlox liven up an entire landscape.

Use this plant in pollinator patches, meadow gardens, perennial borders, cottage gardens, mall plantings, cut flower containers and gardens to add a splash of color.

Hummingbirds love them.

This plant also looks great when used in front, back, or between the borders.

Summer phlox has been utilized as a medicinal herb.

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