 Caring for Fresh Flowers and
Foliage
Next Generation Science / Common Core Standards Addressed!

CCSS.ELA Literacy. WHST.11‐12.6 Use technology, including the Internet, to
produce, publish, and update individual or shared writing products in response to
ongoing feedback, including new arguments or information.
Bell Work / Student Objectives
 1. Explain the basic requirements of cut
flowers.
 2. Understand the causes of deterioration and
death of flowers.
 3. Describe the steps of effective conditioning
of flowers and foliage.
 4. Explain the importance of using floral
preservatives.
 5. Learn about commercial packing and
shipping.
Vocabulary
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Acidic
Alkaline
Bent necks
Conditioning
Ethylene inhibitors
Graded
Hard water
Hardened
Photosynthesize
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Precooled
Respiration
Salinity
Senescence
Soft water
Stem blockage
Transpiration
Turgid
Interest Approach
Here is a package of flowers I
purchased from a florist. Inside is a
packet of preservative. What do you
think the preservative is made out of?
Why do the flowers need it? Notice that
some of my flowers are not looking so
healthy. What do you think is the cause
of their deterioration?
When a Flower Is Cut, What Are
Its Needs?
 Even though flowers have been
removed from a plant, it still
photosynthesizes - produces
food from sunlight.
 There are certain requirements
that are needed by the flowers
in order to survive: water,
food/sugar, healthy
environment and sanitation.
 High quality water
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A flower is 90% water. When a
plant has enough water it is said
to be turgid. As flowers
photosynthesize, they need water.
Flowers like acidic water (pH
below 7). This allows for better
water uptake. Perform a pH test
to determine if the water is acidic
or basic (pH above 7).
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Ph is the amount of hydrogen ions or
hydroxide ions in the water.
Preservatives make the water more
acidic.
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Water is classified as either
hard water (which contains a
high level of minerals), or
soft water (which has been
treated to lower mineral
levels)
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Hardness effects the pH
Salinity is the measurement
of the total dissolved salts in
water.
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Salt clogs the xylem of the stem
preventing water movement.
– Causes wilting and weakening of
stem.
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Must be less than 200 ppm.
 Food and sugar
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Cut flowers are in need of
sucrose and dextrose
(glucose).
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The flower gets these from the
stored sugar it has and from the
provided preservatives.
 Healthy environment
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Flowers need an environment
free of ethylene gases, which
causes deterioration of flowers.
Fruit should not be stored in a
cooler because they give off
ethylene gas.
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Conditioning (the process of treating
flowers in order to extend their life) occurs
when the flowers and foliage arrive at the
design site.
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Warm water should be used - between 100 to
1100F; Better for uptake.
Recut stems and remove lower foliage.
Leave flowers out at room temperature for 2-3
hours; Again it is better for water/food uptake.
Once the flowers are hardened off (full of
water after conditioning), they can be put
into a cooler of 34-380F.
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Coolers provide better humidity control than
regular refrigerators.
 Sanitation
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These are procedures used when handling
fresh flowers that will ensure they last
longer.
Hands, knives, shears, containers and
work area need to be kept sanitary.
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Use a disinfectant soap to clean tools and work
area; Also use bleach to clean the buckets.
Bacteria can be reduced by continual
cleaning of work areas, coolers and
containers on a regular basis.
What Causes a Flower to
Deteriorate and Die?
 When a flower is cut from the mother plant, it
starts to die because the flower no longer
has a water or food source.
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Death of a flower is called senescence.
Humans must intervene to provide the
necessary water and food.
 There are five causes of flower deterioration:
genetic life, wilting, harvest time, ethylene
gas and disease/damage.
 Genetic life:
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Each flower has a certain inherent life span
based on its genetics.
Our goal is to achieve the maximum life
span allowed by nature.
Flower:
Daylily
Dutch iris
Rose
Carnations
Chrysanthemums
life span:
1 day
3-5 days
5-7 days
10-14 days
14-21 days
 Wilting:
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Caused by either excessive water loss or
lack of absorption.
Blocked vascular tissue could be another
cause.
Transpiration (water loss in the process of
respiration) is caused by warmer
temperatures and lower humidity.
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Respiration is the process of burning glucose
to create energy.
Stem blockage is the most common
cause of poor absorption; Due to clogged
xylem.
 Timing of harvest:
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This is the time the flowers are cut from the
mother plant.
Time of day - flowers should never be cut
when they are wilted.
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Avoid cutting in the heat of day.
Evening time is best because there is a decrease in
photosynthesis.
Morning time is second best because the plant is
full of water.
Stage of flowering - best time to harvest is
right before the flower fully opens.
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Exceptions include the daisy and flowering bulbs
(harvested as bulbs) and the calla lily (develops
after it is cut).
 Ethylene gas exposure:
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Ethylene gas is a natural plant
hormone produced by aging flowers,
fruits and vegetables
Common signs of ethylene exposure
include large amounts of fallen
petals, dropped florets and yellowing
leaves
Growers and wholesales prevent this
by using ethylene inhibitors products that block or tie up the gas
 Disease or damage:
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Flowers grown/cut should be of the
highest quality
Must always be inspected for
disease/damage
Flowers Sensitive to Ethylene
 Alstroemeria
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Peruvian lily
 Anemone
 Baby’s
breath
 Bouvardia
 Carnations
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Cornflower
Delphinium
Freesia
Lily
Snapdragon
How Are Cut Flowers and Foliage
Conditioned to Maximize Vase Life?
 Conditioning plant materials include the
following steps:
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1. Flowers should be unpacked and inspected upon
receiving.
2. Prioritize the order of processing; Wilt-prone and
expensive flowers first.
3. Remove sleeves, ties and any foliage that might
contact water in the container.
4. Under warm water, re-cut all stems, removing 1-2
inches.
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Warm water has less air bubbles than cold.
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5. Use specific treatment solutions as
needed.
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6 . Place cut flowers in a floral preservative
solution mixed at the proper concentration.
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Ex. Roses should be treated with an additional
preservative.
Too little preservative encourages bacterial
growth; Too much can cause toxicity.
7. Let the flowers remain at room temperature
for 2-3 hours to increase water uptake.
8. Place the flowers in a cooler set at 34-380F
with a high humidity level and constant light.
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9. Milky stems should be treated quickly by
dipping them in boiling water for five
seconds; Then place them in the floral
preservative.
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You can also burn them with a match or put
them in a warm preservative solution.
10. Roses that have lost turgidity near the
flower head are called bent necks.
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They can be revived by placing the stems in a
warm preservative solution and re-cutting them
under water.
Reviving a Bent Neck
Review of Conditioning Process
1. Be sure to start with clean
buckets.
2. Unpack flowers immediately.
3. Remove lower foliage.
4. Re-cut 1-2” off old stem
under warm water.
5. Place flowers in plastic
bucket with floral preservative.
6. Leave flowers out for 2-3
hours.
7. Put flowers into the cooler
to complete the process.
Review of the Basic Needs of
Fresh Cut Flowers
Needs
High Quality Water
Proper pH of 3 to 4.5
Low total dissolved salts
Food
Sugars – supplemented in
preservative solution
Healthy Environment Clean air
Proper temperature
Sanitation
Provide clean water
Use clean tools
How Does a Floral Preservative
Extend the Life of Cut Flowers?
 Floral preservatives will extend the life of cut
flowers as opposed to using plain water.
 A preservative contains sugar as a
supplemental food source, an acidifier to
decrease the pH, and a bactericide to kill
bacteria in a vase or stem.
 Pre-treatments are used before preservatives
to reduce ethylene exposure and to hydrate
flowers that are wilt prone.
 All flowers can benefit from hydration
solution treatment.
How Are Flowers Sent From the
Field to the Florist?
 The majority of cut flowers used in the United
States are produced in foreign countries.
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The commercial packing and shipping process
affects the life span of the flowers.
 Flowers are graded - separated into groups
based on factors such as quality, uniformity and
size.
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Also graded by stem quality, length and strength.
 Flowers are then placed in bundles and sleeved
for shipping.
Common Bunch Sizes for Major
Floral Crops
Bunch Size:
25
10
Variable by Weight
Single
Examples:
Roses, Carnations,
Leatherleaf, Palms
Tulips, Daffodils, Iris,
Delphinium, Liatris,
Snapdragon, Gladioli
Pompon Mums, Baby’s
Breath, Statice
Gerbera Daisies,
Gardenia, Tropical
Orchids
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Some flowers are packaged individually;
For example, gerber daisies.
After bundling, the flowers are boxed for
shipment and precooled - a method of
quickly replacing the warm air with cool air
inside the box; Also known as dry packed.
Flowers such as snapdragons and gladioli
are packed in hampers and stored upright.
Then the flowers are shipped via air and
then truck to the marketplace.
Examples of Flower Packaging
Some flowers are
packaged in
sleeves, like
carnations; some
are packaged
individually, like
Gerbera daisies.
Here, workers are packaging
flowers in bunches, like statice.
Summary
 What do cut flowers need in order to survive
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once they are cut from the mother plant?
What are some causes of flower deterioration?
What causes a flower to wilt?
List the steps involved in processing cut flowers.
Why are floral preservatives added to the water?
How are cut flowers packaged by the growers
and shipped to the wholesalers?
The End!