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A disinfectant or biocide, such as chlorine, copper, or AgNO3, controls harmful bacteria growth and prevents plugging of the conducting tissue through microbial occlusion of xylem vessels. This enhances water and nutrition uptake. Ag+ ions inhibit the rise of ethylene precursor.
Sugar slows the degradation of protein, release of ammonia and the consequent rise in pH. As sugar might promote microbial growth, sucrose might be the better solution.
Slightly acidic water, through citric acid or vinegar, can be more easily transported in the stem and thereby helps to transport water and nutrients.
It is also recommended to keep the flowers cool, out of direct sunlight, and away from ripe fruit. Chemicals such as ethylene from the fruit will ripen the flowers.
These solutions also work for your Christmas tree.
- Sujatha A. Nair, Vijai Singh, T. V. R. S. Sharma, Effect of Chemical Preservations on enhancing Vase-Life of Gerbera Flowers, J. Tropic. Agric. 2003, 41, 56–58.
- Amihud Borochov, Shimon Mayak, Abraham H. Halevy, Combined Effects of Acid and Sucrose on Growth and Senescene of Rose Flowers, Physiol. Plant 1976, 36, 221–224.