Four Star Culture Guide - 2019 - 56

STROBILANTHES
Persian Shield

NUTRITION
pH: 5.8 - 6.2
EC: (2:1 extraction method) .4 - .8
Constant feeding at 100ppm - 150ppm nitrogen with a
fertilizer selected for grower's water quality and soil mix is
recommended.
TEMPERATURE
Rooting out: 68 - 72 F
Growing on: 68 - 75 F
Holding: 65 - 68 F
WATERING
Maintain moderate soil moisture. Allow the soil to cycle from
moist to only slightly dry. Avoid both severe dry downs/wilting
and long periods of wet soil, especially at cooler temperatures.
Growing too wet early in the production cycle can cause disease
issues while severe wilt conditions can damage root systems and
foliage. Controlling moisture levels and growing at moderate to
slightly dry is a good practice to also control plant growth.
TIMING
4" - 5"/Grande™: 6 - 8 weeks with one 104 Liner plant.
6"/1GL Royale™: 8 - 10 weeks with one 104 Liner plant.
8": 9 - 12 weeks with one 104 Liner plant.
PLANTING
The 104 Liner plants should be planted slightly deeper than
the liner root ball into a well-drained soil mix selected to
match individual water quality and fertilizer blends. Water in
thoroughly without saturating the mix and maintain a constant
moderate soil moisture level for the first seven to 10 days to
establish new rooting. Pinching should not be needed except
in the case of taller material at time of planting or for larger
containers. Pinching can be given for larger containers usually
three to four weeks after planting. For larger containers a
second pinch can be performed as needed. Usually a second
pinch would be done as a softer pinch used mainly to shape the
plant.

LIGHT/LIGHTING
Persian Shield should be grown in a moderate to high light
level area of the greenhouse for optimal plant development and
branching. Persian Shield requires long days (+12 hours
per day) for vegetative growth. Persian Shield flowers
when grown under short days. From mid-September through
the first of April these plants should be grown under long days
by providing 14-hour daylengths. This can be done by either
daylength extension lighting or night interruption lighting. This
required lighting can be provided in a manner like that which is
applied to mums or poinsettias.
GROWTH REGULATORS
Growing under proper light conditions, with adequate spacing,
moderate soil moisture levels and recommended temperatures
will produce the highest quality plants and lower the need for
any PGR treatments.
If required, a spray application of B-Nine® (daminozide) at
2,500ppm is effective.
PEST and DISEASE MANAGEMENT
There should be little instance of disease if basic cultural
guidelines are followed. Botrytis and Root Rot can occur in poor
growing conditions if plants are kept too cool or wet. Control
excessive humidity levels in the greenhouse, provide good air
movement, do not over fertilize, and provide adequate space.
Whiteflies, Thrips, Aphids, and Spider Mites can be pests
of concern. Scout crops on a regular basis and use control
measures as needed.
OUTDOOR GROWING SCHEDULE
Strobilanthes are tropical-type plants and should be grown
outdoors only after the danger of frost has past and
temperatures have warmed. The foliage can be damaged from
a very light frost. At Four Star (Michigan) we would only move
these crops outdoors in mid-May if weather allows.

Four Star Greenhouse I www.pwfourstar.com I 734-654-6420
56

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.

http://www.pwfourstar.com

Four Star Culture Guide - 2019

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