Environmental Conditions. Storing or maintaining displays, flowers and plant materials

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1 Environmental Conditions Storing or maintaining displays, flowers and plant materials

2 Precooling Precooling is a step that rapidly brings the temperature of the flowers down from the field temperature to a proper storage temperature. A low temperature slows the respiration rate of the flowers which in turn helps them last longer

3 Precooling The precooling of flowers is a very important step for individuals selling to a large wholesale Market distant markets and if their crop is to be stored for a long time such as peonies

4 Precooling Individuals who sell at a local retail market usually do not need to worry about this step since their flowers will be in the customers home the day they are picked. Cold storage is recommended for all flowers that will not be in the market immediately and any flowers sold wholesale

5 Forced-air cooling Forced-air cooling is the best method for flowers cool air is actively forced with fans through the bunched flower. This can be done when the flowers are in a bucket or when they are packed dry into boxes.

6 Low temperatures Low temperatures slow the respiration rate of the flowers and prolong the vaselife of the flowers. In general, temperatures should be 4-6 C Have a relative humidity of 85 to 90 percent, for most flowers. Flowers should never be stored with fruits and vegetables.

7 Low temperatures Some fruits and vegetables produce ethylene that can dramatically shorten the life of the flowers. Once flowers are bunched into marketable units they should be placed in cold storage As a new grower using local retail markets, a refrigerated cold storage may not be available or affordable.

8 Low temperatures Since most of their flowers will be sold within hours a cool place such as an air conditioned room, cellar or basement could be used.

9 Measurements It is advisable to check your coolroom for efficiency by regularly monitoring the flower temperatures. This can be carried out by using a thermometer or temperature probe to measure temperatures in several cartons throughout the coolroom.

10 Relative Humidity The ratio of water vapor pressure in the air to vapor pressure in saturated air at a given temperature is known as relative humidity (RH). Relative humidity can be determined by comparison of the wet bulb and dry bulb temperatures on a psychrometric chart Devices for measuring these properties are available commercially at a low cost.

11 Relative Humidity Proper RH plays a significant role in increasing longevity of cut flowers. Strive for a RH over 90%, but less than 100%. If water droplets start forming on the flowers and foliage, a common fungus known as botrytis may attack

12 Light Light is not as great of concern however, chronic darkness will cause foliar deterioration. optimum light levels during production are important to ensure high quality cut flowers.

13 Ethylene Flowers generate ethylene gas as a part of the normal aging process. This gas is also given off by several types of ripening fruits, gasoline or propane combustion, and during welding. Air containing 100 parts per billion ethylene ( %) may damage flowers in the vicinity.

14 Ethylene Thus, a very minute amount can wreak havoc in the storage area. Besides avoiding ethylene producing sources near cut flower production and harvest areas, provide proper air circulation for dilution of the gas.

15 Ethylene Silver thiosulfate (STS) reduces harmful effects of ethylene and is readily available in various formulations. This product may be recycled and the costly silver recovered

16 Ethylene In addition, silver is a heavy metal which pollutes soil and groundwater. SuperCan is a silver recovery system long used by individuals in the photographic industry. This system allows the silver to be recycled to save money while sparing the environment.

17 Ethylene Refrigeration also helps to reduce ethylene production and lowers the sensitivity of vulnerable flower species

18 Ethylene Sensitive flowers Agapanthus Freesia hybrids Alstroemeria Solidago spp. Anemone spp. Kniphofia uvaria Astilbe spp. Lilium spp. Gypsophila spp. Bouvardia hybrids Phlox paniculata Campanula spp. Scabiosa spp. Dianthus spp. Rosa spp. Antirrhinum majus Delphinium spp. Matthiola incana Dendrobium spp. Lathyrus odoratus

19 Geotropism Geotropism is a growth response to gravity Unless spikes of flowers such as gladiolus and snapdragon are shipped upright, spikes will bend upward (negative geotropism), causing abnormally shaped flowers. Most flowers, however, can be shipped horizontally.

20 Cut Flower Storage/Display Facilities A number of quality flower coolers are commercially available today. Choose a model that fits your needs and also controls critical environmental factors

21 Cut Flower Storage/Display Facilities When choosing a cooler look for one that not only will provide proper environmental needs, but also will help market the flowers purchase a cooler that is functional and attractive.

22 Cut Flower Storage/Display Facilities One major purchase decision is whether to buy an enclosed or open-air flower cooler. An enclosed cooler controls temperature and humidity to near ideal conditions, allowing for prolonged cut flower storage

23 Cut Flower Storage/Display Facilities An open-air cooler will not maintain the favourable conditions as well as an enclosed cooler but is preferred for customer convenience Open air coolers tend to be more inviting for customers to visit, and are especially appropriate in businesses with rapid turnover of floral stock

24 Hot weather When flowers are exposed to heat, they respire at a greater rate than at lower temperatures. Respiration is basically what causes ageing in most living organisms. Flowers have high rates of respiration. The cooler the room or location they are displayed, the longer they will last.

25 Cold conditions below 4 degrees Celsius Conversely, actual internal flower cells can easily become damaged if subjected to very low temperatures Flowers grown in tropical areas, such as Orchids and Anthuriums, are particularly susceptible to low temperature damage Never put your flowers in a freezer or anywhere that is below 4 degrees Celsius

26 Draughty positions Draughty positions are also unfavourable spots to locate your flowers. The petals tend to dry out and respire more quickly in these areas. A corner position is preferable to a hallway or near open doors.

27 Direct sunlight Flowers which are subjected to direct sunlight can easily become overheated, resulting in an increased rate of respiration and the drying out of petals etc, leading to reduced vase life.

28 Air conditioning It has been noted that usually with air conditioning (especially in large offices or stores), fresh flowers tend to dry out very quickly. This is particularly the case with flowers that have large, exposed petals.

29 References Armitage, A.M., 1991 The Georgia Report Stage of flower development at harvest. The Cut Flower Quarterly 3(1):13. Armitage, A.M., Specialty Cut Flowers. Timber Press, Portland OR USA. Hardenburg, R.E., A. E. Watada and C. Y. Wang, USDA ARS Agricultural Handbook Number 66, The Commercial Storage of Fruits, Vegetables, and Florist and Nursery Stocks. Nowak, J. and R.M. Rudnicki, Postharvest Handling and Storage of Cut Flowers, Florist Greens and Potted Plants. Timber Press, Portland OR USA. Sacalis, J.N., Cut Flower Prolonging Freshness Postproduction Care and Handling 2nd ed., edited by Joseph L. Seals. Ball Publishing, Batavia, IL USA