Phlox Opening Act Blush

Perennial Solutions: Phlox ‘Opening Act Blush’ By Paul Pilon

This new hybrid begins flowering in early summer and is a great addition to the landscape with its appealing garden presence.

Each year many gardeners and landscapers anxiously await the arrival of the spectacular summer flower displays of the landscape staple garden phlox. Now thanks to the breeding efforts of Walters Gardens, the wait can be shorter. ‘Opening Act Blush’ is a new hybrid phlox that begins flowering in the early summer, several weeks before traditional garden phlox varieties, and continues flowering well into the summer.

‘Opening Act Blush’ has dark green, glossy disease-resistant foliage and forms clumps reaching 18 to 20 inches in both height and width. The light lavender-pink flowers begin to cover the foliage in the early summer and continues to bloom as long into the season as does traditional garden phlox. Some reblooming occurs before the end of summer; deadheading will encourage more flowering. The lightly fragrant flowers attract hummingbirds, butterflies and other pollinators into the landscape.

This new hybrid phlox is cold hardy throughout Zones 4 to 9. Additionally, another great attribute of ‘Opening Act Blush’ is it can take quite a bit of heat and humidity. This hybrid phlox prefers locations with lots of sun, adequate drainage and sufficient air movement.

With these attributes and strong garden performance, ‘Opening Act Blush’ was selected and introduced as a Proven Winners perennial. This hybrid phlox makes a great addition to the landscape and can be used in borders or mass plantings. Additionally, it can be used in containers or as a cut flower. With its soft flower coloration, manageable plant size and appealing garden presence, ‘Opening Act Blush’ would make a great addition to your perennial program.


Plant patents for phlox hybrid ‘Opening Act Blush’ have been applied for (USPPAF, Can PBRAF). Therefore, unlicensed propagation of this cultivar is prohibited. Licensed propagators can easily propagate them when following a few guidelines.

Stick the cuttings into liner flats containing a stabilized growing media or propagation substrate that has been moistened prior to sticking. Rooting agents are optional as they will root readily without these compounds. Place the cuttings under a low to moderate misting regiment for about the first four to six days of propagation. When possible, it is best to propagate under high humidity levels (90 percent relative humidity) with minimal misting.

Maintain soil temperatures of 65 to 70o F during the rooting process. Fertilizers can be applied continuously with the mist water at 50- to 60-ppm nitrogen or every five to seven days applying 100- to 120-ppm nitrogen with each irrigation. Decrease the amount of mist being delivered as the roots begin to develop; misting can generally be removed altogether at 12 to 16 days after sticking. Liners take approximately six to eight weeks from sticking to become fully rooted and ready for transplanting.


Phlox ‘Opening Act Blush’ can be grown in various container sizes ranging from 1 quart to 2 gallon sized pots. Hybrid phlox performs best when grown in a moist, well-drained growing mix. Many commercially available peat- or bark-based growing mixes work well provided there is good water holding ability and adequate drainage.

Phlox 'Opening Act Blush'
Phlox ‘Opening Act Blush’

They can be potted during the late summer of the year prior to the intended market date or during the spring of the same year using vernalized liners. Plant one liner per pot when transplanting into 1 quart to 1 gallon sized containers and three liners per container when transplanting into 2 gallon sized pots. ‘Opening Act Blush’ can also be planted using bare root starting materials. The liners should be planted so the original soil line of the plug is even with the surface of the growing medium of the new container. When using bare root, plant them so the crown is just below the surface. To improve fullness and plant quality, it is beneficial to soft pinch the plants one to two weeks after transplanting.

Hybrid phlox perform best at light to moderate fertility levels. When using water- soluble fertilizers to deliver nutrients, apply 75- to 100-ppm nitrogen with every irrigation or 200 ppm as needed. Controlled-release fertilizers can be incorporated into the growing mix prior to planting at a rate equivalent to 0.9 to 1.1 pounds of elemental nitrogen per yard of growing medium or applied as a topdress onto the media surface using the medium labeled rate. The pH should be maintained at 5.8 to 6.2.

Phlox require average amounts of irrigation. It is best to keep them uniformly moist but not consistently wet. When irrigation is needed, water thoroughly and allow the medium to dry slightly between waterings.

With its compact habit, controlling plant height may not be necessary when producing ‘Opening Act Blush.’ Providing adequate spacing between the plants will reduce plant stretch caused by competition. If toning is required, spray applications of 2,000-ppm daminozide (B-Nine or Dazide) plus 3-ppm uniconazole (Concise or Sumagic) can be applied as needed.

Insects and Diseases

Hybrid phlox can be produced with relatively few problems from insect feeding or plant pathogens. Aphids and thrips are the most prevalent pests. Also, watch for caterpillars, leafhoppers, spider mites and whiteflies feeding on them. Although ‘Opening Act Blush’ shows excellent resistance to diseases and can generally be grown without the incidence of plant pathogens, growers should watch for Alternaria, Botrytis, crown and root rots, leaf spots and powdery mildew. Growing them with proper plant spacing under high light intensities, providing good air circulation, and maintaining moderate humidity levels (less than 75 percent) will greatly decrease the incidence of diseases. Routine scouting should be sufficient to detect the presence of any pests or diseases and to determine if and when control strategies are necessary.

Temperatures and Scheduling

Phlox ‘Opening Act Blush’ naturally flowers in the early summer, but can be easily produced for earlier sales in bloom. It requires eight to 10 weeks of vernalization with temperatures between 35 and 40° F for flowering. After the cold treatment, they can be grown under natural day lengths. ‘Opening Act Blush’ can be grown into flower in eight to 10 weeks when they are grown with temperatures of 60 to 65° F. The highest quality plants are produced in high light environments (minimum 3,000 foot-candles). Under low light intensities, overall quality and the quantity of flowers per plant are reduced.


Phlox hybrid ‘Opening Act Blush’ is being marketed by Proven Winners. Liners and bareroot are available from Walters Gardens Inc. Liners may also be available through several Proven Winner propagators.

Paul Pilon

Paul Pilon is a horticultural consultant, owner of Perennial Solutions Consulting (www., and author of “Perennial Solutions: A Grower’s Guide to Perennial Production.” He can be reached at 616.366.8588 or paul@