Wild blue phlox (Phlox divaricata)

Also known as: Wild sweet william

The wild blue phlox (Phlox divaricata), also known as woodland phlox or Louisiana phlox, is native to eastern North America. This plant features flowers on hairy, sticky stems and often thrives along stream banks in its natural habitat. The name "phlox" originates from the Greek word for "flame," chosen for the species due to its strikingly vivid flower colors.

In This Article

Care Tips Water Sunlight Temperature Soil Fertilize Prune Propagation Repotting

Attributes of Wild blue phlox

Lifespan

Perennial

Plant Type

Herb

Plant Height

15 cm to 30 cm

Spread

50 cm

Leaf Color

Green

Flower Size

2.5 cm to 8 cm

Flower Color

White Blue Purple Lavender

Images of Wild blue phlox

Quickly Identify Wild blue phlox

Lush green leaves, 2 inches (5 cm) long, with fine hairs and sticky texture.

Vibrant blue tubular flowers, 1.5 inches (3.8 cm) wide, with recessed stamens.

Ovoid fruit capsules, 0.2 inches (5 mm) long, containing small black seeds.

Slender stem, 0.1-0.2 inches (2.5-5 mm) thick, hairy and sticky with sparse branching.

Cluster-forming herbaceous perennial, 6-12 inches (15-30 cm) tall, growing on forest floors.

Scientific Classification of Wild blue phlox

Phylum

Vascular plants

Class

Dicotyledons

Order

Ericales

Family

Phlox

Genus

Phloxes

Species

Wild blue phlox

Planting and Growing of Wild blue phlox

Care Difficulty

Easy

Watering Schedule

Every 2 days

Sunlight Requirements

Partial sun

Sunshine Duration

6-10 hours

Ideal Temperature

65-75℉

Soil Type

Potting Mix, Peat Mix

Soil pH

6.5-7.5

Fertilizer Type

Balanced

Pruning Season

Spring, Summer

Pruning Area

Branches, Leaves

Pruning Frequency

2 times a year

Repotting Season

Spring

Pot Type

Plastic, Ceramic

How to Water Wild blue phlox?

For Phlox divaricata, the key is to maintain consistently moist soil without waterlogging. Approximately 500 ml per watering is ideal, ensuring the soil feels damp to the touch without being overly saturated. Water until the top few inches are uniformly moist, indicating sufficient hydration without drenching the roots.

What are the symptoms of an underwatered Wild blue phlox? ›

What should I do if my Wild blue phlox is not getting enough water? ›

What are the symptoms of an overwatered Wild blue phlox? ›

How to save an overwatered Wild blue phlox? ›

More About Watering Techniques→

What Are the Sunlight Requirements for Wild blue phlox?

Sunlight Requirements: Partial sun, Full shade

Duration of light: 3 to 6 hours daily

Phlox divaricata thrives best in partial sun or full shade conditions. Ideal light encourages vibrant blossoms and robust foliage, creating a healthy and visually appealing plant.

How much sunlight is ideal? ›

Solutions for obtaining ideal sunlight? ›

Benefits of achieving ideal sunlight? ›

More About Sunlight Requirements Techniques→

What Is the Ideal Temperature Range for Wild blue phlox?

Ideal Temperature: 65 ~ 75℉

The ideal temperature range for Phlox divaricata is between 65°F and 75°F. This range helps ensure optimal growth and blooming. Temperatures within this range allow the plant to maintain healthy metabolic processes and develop strong, vibrant flowers.

What Soil is Best for Wild blue phlox?

Soil type: Loam, Sandy loam

Soil PH: 6.5 ~ 7.5

Phlox divaricata thrives in well-drained soil, which prevents waterlogging and root rot. This ensures that the plant's roots receive adequate oxygen, promoting healthy growth and flower production. The soil should retain enough moisture to keep the plant hydrated without becoming waterlogged. This balance supports sustained flowering and prevents the wilting of the plant during dry spells. A soil rich in organic matter provides essential nutrients, enhancing the health of Phlox divaricata. Organic matter improves soil structure, promotes beneficial microorganisms, and increases nutrient availability. More About Soil→

How to Fertilize Wild blue phlox?

Fertilizer type: Balanced

For Phlox divaricata, use a balanced, water-soluble fertilizer diluted to half strength. Avoid over-fertilizing, as this can lead to leggy growth and reduced flowering. A teaspoon in a gallon of water will suffice for liquid applications. More About Fertilizing Techniques→

How to Prune Wild blue phlox?

Pruning Time: Spring, Summer

Monitor the growth pattern of Phlox divaricata; if it becomes too leggy, a mid-season trim in early summer can help maintain a compact shape. Be cautious not to prune more than one-third of the plant at any one time, as overpruning can stress the plant and negatively affect its growth. Remove all cuttings and debris from the base of the plant to prevent pest infestations and ensure good air circulation around the plant. More About Pruning Techniques→

How to Propagate Wild blue phlox plant?

Propagate Time: Spring, Early spring, Late spring

Collect seeds from matured phlox flowers in late summer. Let them dry and store them in a cool, dry place until you are ready to plant in early spring.

Select healthy stems and cut 4 to 6-inch sections. Remove the lower leaves and place the cut ends in a rooting hormone before planting in well-draining soil or a container.

In early spring or late autumn, carefully dig up the plant. Separate clumps using a clean knife or spade and replant the divisions into appropriate garden spaces or pots.

More About Propagating Techniques→

How to Repot Wild blue phlox plant?

Repotting frequency: Every two years

Phlox divaricata shows it needs repotting when its roots start circling the container and it appears cramped and unhappy. If growth seems stunted and despite proper care it's not thriving, these are key indicators that repotting is necessary to refresh the soil and give roots more room.

Select a pot that is about two inches larger in diameter than the current one. The extra space allows roots to expand without stress. A pot with drainage holes at the bottom is essential to prevent waterlogged conditions, which can lead to root rot. A clay or terracotta pot is a good choice, as it is breathable and prevents overwatering.

Phlox divaricata thrives best in well-draining, rich soil. A good potting mix with organic matter enhances nutrient availability and drainage, preventing sogginess. It should support healthy root growth by allowing air circulation. Adding some perlite or sand structures the soil better, balancing water retention and drainage.