Four Star Culture Guide - 2019 - 55

SOLENOSTEMON (COLEUS)
NUTRITION
pH: 5.8 - 6.2
EC: (2:1 extraction method) .6 - .9
Constant feeding at 150ppm - 200ppm nitrogen with a
fertilizer selected for grower's water quality and soil mix is
recommended.
TEMPERATURE
Rooting out: 65 - 72 F
Growing on: 65 - 72 F
Holding: 60 - 62 F
WATERING
Maintain moderate soil moisture. Allow the soil to cycle from
moist to dry. Avoid both severe dry downs/wilting and long
periods of wet soil, especially at cooler temperatures. Growing
at lower moisture levels can be beneficial towards producing
a more compact plant with fewer PGRs required. This practice
can also be used to help "hold" plants.
TIMING
4" - 5"/Grande™: 4 - 5 weeks with one 104 Liner plant.
6"/1GL Royale™: 6 - 7 weeks with one 104 Liner plant.
8": 8 - 9 weeks with one 104 Liner plant.
PLANTING
The 104 Liner plants should be planted 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
a pinch on plants for larger containers. This pinch can be given
for larger containers usually two to four weeks after planting.
Pinching will increase crop time by two to three weeks.
LIGHT/LIGHTING
These plants should be grown in a medium to high light area
of the greenhouse for optimal plant development. Most have
been bred to grow in full sun. Growing in a heavily shaded
area will produce taller and softer growth that is less attractive
and more disease-prone.

GROWTH REGULATORS
If required, a spray application of B-Nine® (daminozide) at
2,500ppm is effective. Also, a tank mix spray of B-Nine at
2,500ppm and Cycocel® (chlormequat) at 1,000ppm - 1,500ppm
can be applied. Other materials such as Sumagic® (uniconazole),
Bonzi® (paclobutrazol), Topflor® (flurprimidol) and Piccolo®
(paclobutrazol) can be used, but care should be taken. Coleus
are very responsive to these products and small trials should be
done before large scale applications are made. Cooler growing
temperatures and especially drier growing practices can be
very helpful at managing plant size.
PEST and DISEASE MANAGEMENT
There should be little instance of disease if basic cultural
guidelines are followed. Botrytis and soft stem rots can
occur in poor growing conditions. Control excessive humidity
levels in the greenhouse and provide adequate air movement.
Avoid over-watering or periods of excessive moisture on the
plants' foliage. Provide adequate space for the plants. A
preventative broad spectrum fungicide application at or shortly
after transplant can be helpful if problems have occurred in the
past. Whiteflies, Thrips, and Aphids can be pests of concern.
OUTDOOR GROWING SCHEDULE
Solenostemon finish best in a controlled greenhouse
environment, but can be moved outdoors after all threat of frost
has passed and weather is consistently warm (late May to early
June in Michigan). This recommendation is based on average
spring weather and should be adjusted for unseasonably severe
or unseasonably mild conditions.
OTHER TIPS
Coleus are relatively easy to grow if proper growing conditions
and watering practices are followed. Grow on the moderate
to slightly drier side, provide good air movement and give
adequate spacing to the plants. For the most accurate finishing
dates of Coleus:
* Add an additional week of crop time to Merlin's Magic, Pink
Chaos and Dark Star.
* Reduce by 1 week crop times for Royale Apple Brandy®,
Lime Time™, and Velveteen®.

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