Transcript Poinsettias

Potted Plants
Poinsettias
Topic #2173
Nick Wendling
The Poinsettia
• The flower is small and yellow
• The flower is located in the bracts
• Bracts are the leaves that give the
poinsettia their color
• Poinsettias need short days to develop the
flower, which is necessary for bract
coloring.
The Poinsettia
• Poinsettias should be grown in full sunlight
during long days to develop leaves and
increase stem length.
• The plant develops the flower buds
naturally during late Sept. and early Oct.
• The bracts get their color in Nov. and Dec.
The Poinsettia
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http://www.poinsettiaonline.com/stores/webpage.cfm?WebPage_ID=14&DID=30
Greenhouse Management
• Factors to Consider
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Light
Temperature
Moisture
Ventilation
Climate
http://www.igcusa.com/ghse.htm
Light
• The greenhouse should be
located to receive maximum
available sunlight.
Temperature
• Day temperature 5 to 10 degrees higher
than night temperature.
• Night temp should be 65 degrees with day
temp being around 70-75 degrees.
Moisture
• Plant growth is dependent on moisture
• Watering helps to carry dissolved nutrients
to the plant.
• The amount needed is dependent on the
outside conditions. (sunshine or clouds)
Ventilation
• Ventilation is the movement and exchange
of air in the greenhouse.
• This ensures proper temperature
throughout the greenhouse.
• Helps control relative humidity and plant
diseases.
Planting and Spacing
• Poinsettias can be grown in any size pot.
• The size of the pot will determine the
overall size the plant will grow to.
• In larger pot sizes, often more than one
plant is planted. (3 plants in a 6in pot or
bigger)
Pinching
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Removal of the terminal bud
Four or five nodes should remain
Increases the number of bracts per plant
Causes the plant to be fuller
Soil Mixes
• Needs to be porous and well drained
• Soil should be free of insects and diseases
• Soil should be sterilized at 180 degrees for
thirty minutes.
Fertility
• Poinsettias require a regular fertility
program
• Use a complete fertilizer (contains
Nitrogen, Phosphorus, and Potassium)
• 20-10-20 is a commonly used formulation
Growth Regulator
• Control the height of plant so it stays a
marketable height.
• Enhance the color of the bracts so it is
more desirable.
Insects
• Common insects are whiteflies, mealybugs,
spider mites, and fungus gnats
• Can be controlled by chemicals
• IPM methods can be used for control
• Keep the greenhouse clean to prevent
insect in the first place
http://www.corkyspest.com/mealybugs.html
Disease
• Common diseases are root rot and powdery
mildew.
• Can be controlled by use of fungicides
• Ensuring the soil is clean before planting is
best way to prevent disease.