Transcript NCSU Cut Flower Research

Production of Poinsettias
by Paul Thomas
Teaching Curriculum Review
Summer 2004
Markets
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Retail
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Garden centers
Florists
Mass markets
Farmer’s markets
Tents
Mail order/internet
Markets
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Wholesalers
Auctions
Brokers
Potted Flowering Plants
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Poinsettias
All other species
Orchids
Chrysanthemums
Azaleas
Bulbs
Easter lilies
Roses
African violets
$247 million  3%
$201
$106
$77
$53
$52
$37
$30
$20
Poinsettias
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Poinsettia, Christmas
flower
Euphorbia
pulcherrima
Euphorbiaceae
Native to S. Mexico
and N. Guatemala
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Number one potted
flowering plant in the
US.
Major crop in Europe
and Australia, minor
elsewhere.
Also, hanging basket
plant, cut flower, and
landscape shrub.
Terminology
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Bracts
Transition bracts
Cyathia
Nectaries
‘Flowers’
Cultivars
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Free-branching vs.
restricted-branching
Bract color
Cultivars
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Foliage color
Height/vigor
Response group (6.5 to 10)
Postharvest life/leaf retention
Series
Cut Flowers
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Renaissance Red
Propagation
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Seed only for breeding purposes.
Terminal cutting propagation.
Purchase cuttings vs. grow your own.
Thick (1/4 in. thick), 2-3 in. long cuttings
with one mature leaf and several immature
leaves.
Don’t forget about stock plants.
LD
Propagation
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Sanitation
75 to 77oF media
Less than 2000 fc light
Foam vs. direct stick
Rooting hormone (0.1% IBA)
Tenting vs. misting
Propagation
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Cutting tips uncovered.
100-150 ppm N weekly, starting 10 days
after propagation.
PGR may be applied prior to cutting
harvest or during propagation.
Cuttings ready to plant in 3.5 to 5 weeks.
Flowering Control
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SD plants
11.75 hr critical night length
Artificial SD often from 5 pm to 7 am, 14 hrs
Sept. 25 natural date of flower initiation
Night temps above 70oF may delay flower
initiation, above 75oF may delay development
Continue SD until pollen shows
Temperature
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Propagation
75 to 77oF media
After propagation* 65 to 68oF
After pinch*
62 to 65oF
End of crop#
55 to 60oF
*Use
of DIF may determine day temperature
*Warm weather often results in higher temps than
indicated
#Multiple crops often prevents lowing temps
Temperature
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Maximum temperatures: below 70F night
and 90F day.
Minimum: 55F anytime.
Light
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Maximum light
• 3500 to 4500 fc for dark leaved cultivars
• 5000 to 6000 fc for light leaved cultivars
• Full sun most of the time
 Shade for 1-2 weeks after planting if high
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temperature and/or low humidity
Specific cultivars may need shading during
production or at finish
Water
 Don’t allow to wilt, especially during hot
sunny days.
Carbon Dioxide
 Not proven to be beneficial.
Nutrition
 Requires overall high rates.
 Nitrogen (CLF)
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225 to 300 ppm N overhead irrigation.
100 to 225 ppm N subirrigation.
25% less for dark-leaved cultivars.
Keep ammonium below 30% of N and
eliminate the last 3-4 weeks.
Nutrition
 Phosphorus – 40 ppm
 Potassium – equal to
or 25-50% less than
nitrogen
Nutrition
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Calcium – low levels cause several
problems.
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Leaf edge burn
Bract edge burn
Keep media pH 5.5 or higher and spray 200
to 400 ppm calcium chloride starting with
first bract color.
Nutrition
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Magnesium - High requirement of 40 to 50
ppm CLF or monthly drenches of 8-16
oz./100 gal. of magnesium sulfate.
Boron – Sensitive to toxic and deficiencies.
Molybdenum – high requirement of 0.1
ppm CLF or one drench of sodium
molybdate.
Nutrition – B and Mg Deficiency
Nutrition – Fe Deficiency
Soluble Salts
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Pourthru
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1.9-2.6 dS/m during establishment
2.8-4.1 during growing phase
1.9-2.7 during finishing
1:2 dilution – 0.75 to 1.5 dS/m.
Lower EC with dark-leaved cultivars.
Low EC Problems
High pH problems
Media
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Well-drained, yet retain water.
pH 5.8 to 6.3.
Height Control
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Cultivar
Culture
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 or  days from pinch to start of short days.
Nutrition
‘Dry’ or ‘wet’ growers
DIF/DROP
Chemicals – apply starting approx. 2 weeks after
pinch, stop by early Oct. in NC, one last
opportunity in early Nov.
Chemical Height Control
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Cycocel – 1000 to 1500 ppm, occ. phytotoxic
B-Nine – rarely used alone – not effective, used
as tank mix with Cycocel, 750-2500 ppm BNine/1000-1500 Cycocel
Bonzi – 5-20 ppm spray, 0.5 to 3 ppm drench,
only PGR acceptable for late-season control in
early Nov.
Sumagic – 2-5 ppm spray
Spacing
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Maximum space possible.
Delayed spacing will increase height.
12 x 12 inches now common for 6 or 6 ½
inch pots
Pinching
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Pinched vs unpinched plants
Plants pinched when roots are visible at the
edge of the media, typically 10 to 14 days
after potting.
Premature or delayed pinching – poor
branching
Number of shoots = nodes – 1
Pinching
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Soft pinch – apex removed above immature
leaf.
Hard pinch – apex removed above most
recently mature leaf.
Soft pinch with leaf removal – remove leaf
blades of immature leaves.
Support
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Rings commonly used for higher quality
crops.
Support rarely used for mass market crops.
Marketing Periods
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Pre-Thanksgiving – most rapidly 
Thanksgiving to Dec. 10 – primary
Dec. 10 to Dec. 25
Schedule
Cultural Step
Weeks
Date
Prop. cuttings
3.5-5
mid July
Pot cuttings
1.5-2
late Aug.
Pinch plants
1.5-2
Early/mid Sept.
Start SD
8-12
Finish
13.5-21
mid Nov. – early Dec.
Schedule
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Select proper response group
Use LD or SD to manipulate schedule
Insects
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Whiteflies
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Often shipped in
with cuttings
Fungus gnats
Others: Lewis mites,
thrips, spider mites,
mealybugs,
caterpillars
Diseases
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Stem and root rot
Botrytis blight
Bacterial stem and
leaf rot
Powdery mildew
Fungal blight and leaf
spots
Viruses
Diseases
Physiological Disorders
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Bract necrosis
Leaf edge burn
Stem breakage
Cycocel damage
Physiological Disorders
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Leaf drop
Splitting
Leaf distortion
Center bud drop
Postharvest
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Increase by reducing temperature to 55F last 1-3
weeks.
Do not use ammonium or urea after mid-late Oct.
Harvest when at least one cyathium shows pollen.
Keep storage and shipping as short as possible
and temps above 50F.
Unpack, unsleeve, and water as soon as possible
Dressing A Poinsettia
Allow them to select a poinsettia
After the selection…..
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Remove all dead leaves or debris from the
top of the pot
If soil is moist, do not water- if dry, water it
lightly
Allow customer to select foil, bow, and
ribbon colors
Suggest something if they don’t know what
colors look best together.
Check Water & Be Careful
Carefully, Cut the foil….
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You need 13 inches
Be sure to measure it
Cut it on the INSIDE
Fold 1/4 of the all
edge areas to the
inside.
If you rip the foil or
put a hole in it, get
another one.
Place the poinsettia on the foil
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Make sure the pot is in
the center of the foil
Carefully pull up one
corner and DO NOT
TUCK IT.
Tuck the foil between the
corners.
Fold it gently over the
edge of the pot.
Foil the edges...
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Bring the foil up on all
sides of the plant
BE VERY CAREFUL
Crease and turn, crease
and turn
Lift the leaves, do not
smash them against the
pot.
Be PATIENT
Add the bow
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Select the ribbon
color
Cut it to length and
follow the book
directions for a pinch
bow.
Add the pick
Wrap the wire around
the wooden part
Bow with wooden pick
The ribbon around the pot
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Select the ribbon
color
Cut 24-25 inches of
ribbon
Diagonally cut the
edges of the ribbon
Wrap it around the
pot and foil to be sure
it is long enough
Inserting the Bow
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Put the pot ribbon on the
pot
Pull the two ends
together
Cross the ends at the top
between two corners forms an “X”
Push the bow with pick
through the ribbon.
Add the care tag
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Tells them how to
care for the poinsettia
Contains name of
purchaser
Advertises the Craig
FFA
Allows for easy
removal of prices
Protect the poinsettia
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Ask when it will be
taken home
They will not tolerate
more than a few
hours of chill
Sever chill = death in
minutes
Put a plastic bag with
air around the plant
SAY “THANK YOU!”
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Be sure the thank them for the sale
Collect the funds
Record the sale and issue a receipt
Ask if you can take it out to the car for
them
Be polite and helpful
as if your paycheck depended upon it!