Flower Preservation Technology
For netizens who pay attention, this article explains the knowledge of fresh flower maintenance, including flower preservation technology. Next, the editor will introduce it to the netizens.
1. Issues to be aware of in the cultivation of flower preservation Flower preservation is a very important task in the production, storage, and distribution of commercial flowers. Therefore, it is first necessary to ensure the quality of the flowers being cultivated, providing strong and high-quality flower products. The selection of flower varieties is also a very important aspect. For example, choosing a thick-stemmed cut flower variety of the African daisy, due to the high starch storage, can maintain respiration for a long time, thus having a long life span and strong stem strength, and is not easily broken. The experiment on the selection of Dianthus caryophyllus varieties shows that varieties with less acidity have the longest vase life.
In flower cultivation, strengthening management; good growth and development of flowers can increase the dry matter content of flowers, extending the preservation time and vase life of cut flowers. Excessive application of nitrogen fertilizer will reduce the vase life of cut flowers. Therefore, before the color appears in the flower bud, it is necessary to apply less or stop applying nitrogen fertilizer, and at the same time, use potassium fertilizer appropriately to increase the折断 resistance of the flower branches and the transport capacity of assimilates. Now, in some greenhouses and plastic tunnels, the application of CO2 can increase the photosynthesis of flowers, improve the dry matter content, and extend the vase life of flowers.
Watering should also be controlled appropriately to keep it moist, which is beneficial for root development. Pest and disease damage can also directly affect the quality of flowers and should be controlled. Most cut flowers are harvested during the bud stage, which is conducive to controlling the opening and development of cut flowers and also reduces the adverse effects during field, storage, and transportation, thus improving the quality and extending the life of cut flowers. This has been applied in the production of many cut flowers such as Dianthus caryophyllus, chrysanthemum, rose, gladiolus, African daisy, bird of paradise, baby's breath, tulip, and snapdragon.
2. The process of flower cold storage preservation
Flower cold storage preservation is based on the principle that low temperature can weaken the vital activities of flowers, slow down respiration, and reduce energy consumption, using cold storage to delay the aging process, while avoiding discoloration, deformation, and the growth of germs. For example, chrysanthemum cut flowers can be preserved for 7 days at a humidity of 85%-90% and a temperature of 20-25°C, 14 days at 2°C, and 30 days at 0°C. Different types of flowers have different temperature requirements for cold storage preservation. Generally, flowers originating from temperate zones are suitable for storage at 0-1°C, while those from tropical and subtropical zones are 7-15°C and 4-7°C respectively, with a suitable humidity of 90%-95%. In addition, cut flowers can be stored in two ways: wet storage and dry storage. Wet storage is placing cut flowers in a container with water, usually suitable for short-term and small-scale preservation, such as Dianthus caryophyllus, lilies, and African daisies. Dry storage is suitable for long-term storage of cut flowers, using film packaging to reduce moisture evaporation and lower respiration, which is beneficial for extending life.
3. The process of flower chemical preservation
The application of flower chemical preservation is also very widespread, using some chemical substances to regulate and control their growth, physiology, and metabolism, to maintain the freshness of flowers for a longer period, which is very necessary in production and circulation. Using some antitranspirants such as wax, high-grade alcohols, and silicon resins to prevent the opening of the plant's stomata, reducing transpiration, thereby enhancing drought resistance and extending life, as well as having a fungicidal effect. This is especially effective in cut roses. Cut flower preservatives, developed in the past few decades, have been increasingly widely used in cut flower preservation due to their significant effects.
According to their method of action, time, and purpose, cut flower preservatives can be divided into 3 types:
① Pre-treatment solution - used for pre-treatment after cut flowers are harvested and graded, before storage, transportation, and vase insertion.
② Flowering solution - also known as the催花液, used to promote the opening of cut flowers harvested in the bud stage.
③ Vase solution - also known as the maintenance solution, used for cut flowers during the vase viewing period. The composition and type of the preservative varies depending on the type of cut flower. Water is an indispensable component in preservatives. Attention should be paid to whether there are harmful components in the water, such as sodium, calcium, magnesium, and fluorine, which are harmful to some cut flowers. Sodium ions are harmful to Dianthus caryophyllus, while fluoride ions are harmful to chrysanthemum, African daisy, rose, poinsettia, and freesia.
Most preservatives contain sugar, the most commonly used being sucrose, with the sugar concentration in different types of preservatives being roughly pre-treatment solution > flowering solution > vase solution. Sugar has various effects on cut flowers, can supplement energy, improve the nutritional status of cut flowers, and promote life activities. Generally, at least one fungicide is included in various preservative formulations. 8-Hydroxyquinoline (8-HQ) and its carbonates and sulfates (8-HQC and 8-HQS) are the most commonly used fungicides in cut flower preservation. Other fungicides include sodium hypochlorite, copper sulfate, silver nitrate, and zinc acetate. Other ingredients include organic acids and their salts, ethylene inhibitors, antagonists, and plant growth regulators.
4. The preservation process of main cut flowers There are many types of flowers, here are some main cut flower preservation techniques, and other similar ones can refer to the operation. Taking chrysanthemum as an example, since chrysanthemum can still remain fresh after being inserted into water 10 hours after harvesting, no special measures are needed for short-distance transportation, but preservation treatment is necessary for long-distance transportation. Harvest and insert into the pre-treatment solution. When it needs to bloom, insert it into the flowering solution, in a room with a relative humidity of 60%-70% and lighting, it can bloom in 5-10 days. The quality of the flowers is superior to those grown in a greenhouse.
Rose harvesting and preservation
1. Harvesting: The timing of rose harvesting is extremely important for quality and vase life. Harvesting too early can cause the flower head to droop, affecting the stem's ability to transport water to the flower head and leading to early wilting; harvesting too late can shorten the vase life. Generally, for red and pink varieties, it is suitable to cut the flowers when the sepals are reflexed and 1-2 petals are slightly open. Yellow varieties can be harvested slightly earlier than red varieties, while white varieties are slightly later.
2. Preservation: After cutting, the flowers are graded by length, absorb water after 1 hour, then bundled in groups of 10 and wrapped in paper before being packed in a box for sale. If it needs to be stored and transported, the flowers should be moved to a cold room as soon as possible to remove the field heat. The pre-cooled flowers are then transferred to a container at 1°C for storage, with the flower heads wrapped in wax paper or transparent film for protection before being moved to a cold room. The stem base is then inserted into a solution containing 1%-3% sugar, 100-200 mg/L 8-HQS, and aluminum sulfate, citric acid, or silver nitrate for 3-4 hours, then removed and stored. Before storage, dry-stored flowers should be cut 1 cm from the base of the stem and inserted into a sugar-containing fungicide solution for 4-6 hours, then transported in a special container.
Additionally, some people suggest the best preservation method for rose cut flowers is: before 8 a.m., harvest the buds that are about to bloom, immerse in water for 4 hours, then cut 5 cm of the base and immerse it in water, then bundle 20 stems in high-density polyethylene plastic bags, place O2 absorbents or cold storage agents in the bag, pack in a perforated carton, pre-cool at 5°C for 4 hours, then send to the market or consumer through air transportation or refrigerated trucks.
The above content about flower preservation technology can be used as a reference for green plant enthusiasts.