Four Star Culture Guide - 2019 - 75

PHLOX

'Cloudburst,' 'Opening Act Blush'
ZONE HARDINESS 4 - 8
NUTRITION
pH: 5.8 - 6.5
EC: (2:1 extraction method) 0.8 - 1.3
Moderate fertilization is adequate.
TEMPERATURE for forcing from liners
Forcing/Growing on: 60 F Night - 65 F Day
Holding: 40 F Night - 50 F Day
Once plants reach a saleable size, they can be moved to a
cooler open environment with good air movement.
WATERING
Keep the soil evenly moist during all stages of growing.
Phlox paniculata requires average amounts of irrigation.
Avoid watering late in the day to assist in Powdery Mildew
prevention.
TIMING
Supernova® 28 Liner to Trade Gallon/True Gallon: 9 - 11
weeks with one plug per container. A typical planting date
for spring forcing would be Week 10 for finishing in Week 18.
If purchased in the spring, our liners have been vernalized for
proper flowering.
50 Liner to Quart: 9 - 11 weeks with one plug per container.
A typical planting date for spring forcing would be Week 9 for
finishing in Week 18. If purchased in the spring, our liners have
been vernalized for proper flowering. Planting a Standard 50
liner into a gallon and bulking in the fall is also a great way to
finish a high-quality spring crop.
VERNALIZATION
Vernalization will increase plant vigor, decrease time to flower
and improve uniformity of flowering.
PLANTING
Phlox perform best when planted in a well-drained, porous
growing medium. Avoid planting Phlox too deeply, or crop
variability and/or losses from Crown Rots are likely to occur.

LIGHT/LIGHTING
Phlox 'Opening Act Blush' are long-day plants and require at
least 14 hours of light to flower if the plants have not received
a cold treatment. If a fall planting is done, Phlox benefit greatly
from long days and high light during bulking and then high
light during vernalization. Additionally, during forcing, they
also require high light conditions for uniform growth and for
producing a high quality crop.
TRIMMING/PINCHING
Generally, Phlox are forced into flower in the spring and flowers
are formed during the fall. Pinching is only recommended in the
early fall after planting to improve branching and flower count
on the finished plant the following spring. Trimming and shaping
of spent flowers can be done to re-flush color for summer sales.
GROWTH REGULATORS
Effective growth regulators include the tank mixes of B-Nine®
(daminozide) at 2,500ppm + Sumagic® (uniconazole) at 5ppm
or Sumagic alone at 10ppm. Witholding water and fertilizer,
providing adequate space between plants, and finishing them
in an open cooler environment are all good ways of controlling
height on Phlox. Forcing under cooler temperatures will require
a longer overall finished crop time.
PEST and DISEASE MANAGEMENT
Aphids, Spider Mites, Thrips, and Whiteflies are the most
common insect pests observed on Phlox. A good routine
scouting program is recommended to ensure that these and
other greenhouse pests don't cause crop loss. Foliar diseases
should also be scouted for to prevent Powdery Mildew and
Alternaria. Again, providing adequate air movement and
keeping moisture off the plants late in the day will be beneficial
to producing high-quality plants.
OTHER TIPS
When growing larger containers, it is best to bulk them in the
summer the year before they are to be sold.

The rates and chemicals listed are based on our southeast Michigan growing conditions, and are not recommended for nationwide application.
Please adjust the rates and spray applications to your location and facility.

Four Star Culture Guide - 2019

Table of Contents for the Digital Edition of Four Star Culture Guide - 2019