Unit B2-2

Floriculture

Horticulture CD

Problem Area 2

Floral Design

Lesson 2

Caring for Fresh Flowers and Foliage

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?

Student Objectives1. 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

Acidic Alkaline Bent necksConditioning Ethylene inhibitorsGradedHard waterHardened Photosynthesize

PrecooledRespiration Salinity Senescence Soft water Stem blockage Transpiration Turgid

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 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) Ph is the amount of hydrogen ions or hydroxide

ions in the water Preservatives make the water more acidic

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) Hardness effects the pH

Salinity is the measurement of the total dissolved salts in water Salt clogs the xylem of the stem preventing

water movement– Causes wilting and weakening of stem

Must be less than 200 ppm

Food and sugar Cut flowers are in need of sucrose and

dextrose (glucose) The flower gets these from the stored sugar it

has and from the provided preservatives

Healthy environment 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

Conditioning (the process of treating flowers in order to extend their life) occurs when the flowers and foliage arrive at the design site 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 Coolers provide better humidity control than

regular refrigerators

Sanitation 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 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 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: 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: life span:

Daylily 1 day

Dutch iris 3-5 days

Rose 5-7 days

Carnations 10-14 days

Chrysanthemums 14-21 days

Wilting: 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 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: This is the time the flowers are cut from the

mother plant Time of day - flowers should never be cut

when they are wilted 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 Exceptions include the daisy and flowering bulbs

(harvested as bulbs) and the calla lily (develops after it is cut)

Ethylene gas exposure: 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: Flowers grown/cut should be of the highest

quality Must always be inspected for disease/damage

Flowers Sensitive to Ethylene

Alstroemeria Peruvian lily

AnemoneBaby’s breathBouvardiaCarnations

CornflowerDelphiniumFreesiaLilySnapdragon

How Are Cut Flowers and Foliage Conditioned to Maximize Vase Life?Conditioning plant materials include the

following steps: 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 Warm water has less air bubbles than cold

5. Use specific treatment solutions as needed Ex. Roses should be treated with an additional

preservative 6 . Place cut flowers in a floral preservative

solution mixed at the proper concentration 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

9. Milky stems should be treated quickly by dipping them in boiling water for five seconds; Then place them in the floral preservative 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 They can be revived by placing the stems in a

warm preservative solution and recutting them under water

Reviving a Bent Neck

Courtesy of Interstate Publishing

Review of Conditioning Process1. 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.

Courtesy of Corinne Banowski

Review of the Basic Needs of Fresh Cut Flowers

Needs

High Quality Water Proper pH of 3 to 4.5Low total dissolved salts

Food Sugars – supplemented inpreservative solution

Healthy Environment Clean airProper temperature

Sanitation Provide clean waterUse clean tools

Courtesy of Interstate Publishing

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 waterA 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 The commercial packing and shipping process

affects the life span of the flowersFlowers are graded - separated into groups

based on factors such as quality, uniformity and size 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: Examples:

25 Roses, Carnations,Leatherleaf, Palms

10 Tulips, Daffodils, Iris,Delphinium, Liatris,Snapdragon, Gladioli

Variable by Weight Pompon Mums, Baby’sBreath, Statice

Single Gerbera Daisies,Gardenia, TropicalOrchids

Courtesy of Interstate Publishing

Some flowers are packaged individually; For example, gerbera 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.

Courtesy of Delmar Publishing

Summary

What do cut flowers need in order to survive 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?