How to Handle Fertilizer Damage in Daxuesu Orchids

The Yunnan Daxuesu, a fine variety bestowed upon humanity by nature, is deeply adored byorchid growersfor its plant form, flower shape and petals. This has led to the practice of "pulling up seedlings to help them grow," which produces the opposite effect: first, it dampens the enthusiasm oforchid growers; second, it brings certain economic losses; third, it damages the limitedorchidresources. Throughout Yunnan, the great majority oforchid growersgenerally like to plant a few pots of Yunnan Daxuesu, some several hundred pots, forming an industrial scale. In order to achieve great development oforchids, manyorchidenthusiasts often use organic and inorganic fertilizers, with the aim of getting Daxuesu to grow good seedlings and produce good seedlings, so as to receive more economic returns. In reality, in the process of growing orchids, any use of organic or inorganic fertilizer beyond a certain amount will inevitably produce the opposite effect and run counter to one's wishes. I recall that in the spring of 1997, when I was repotting and replanting Daxuesu, each plant was priced at 500 yuan to 600 yuan and considered a top-grade specimen. I was extremely careful and meticulous in both the soil mix and the planting, using sheep manure that had been fermented for nearly a year at a ratio of one-tenth for planting Daxuesu. By the following year, orchid enthusiasts from Chengdu, Sichuan Province, attending the '99 World Horticultural Exposition, purchased eleven top-grade Daxuesu plants. Their leaves were 84 cm long and 1.4 cm wide, with no scorched tips; the roots were 0.2 cm thick, about 90 cm long, and silvery white, coiling within a black ceramic pot 120 cm tall and about 60 cm in diameter, with the root system reaching almost one root per two leaves, achieving a good seedling production rate, strong stress resistance and good adaptability. When the plants were tipped out of the pot, I was very happy. In April this year, I purchased three Yunnan Daxuesu plants at a high price, including one plant from the previous generation and two spring seedlings. When I selected them, they had just been planted by someone else. I was told they had just been planted and did not need repotting this year, so I followed my own management methods. But after some time, a spring seedling 42 cm tall and 1.1 cm wide withered; by early August, I found that another spring seedling not only had scorched tips but also had anthracnose on its other leaves, while the previous-generation old plant showed no disease. To save this pot of Daxuesu, on August 20 I carried out a full soil change using sterilized medium. During the repotting process, the original potting medium contained sheep manure in a disproportionate ratio, which had produced serious fertilizer damage. So I discarded all the original medium and used new medium instead. Judging from the roots, apart from one root 5 cm long whose growing point was damaged, the other nine roots were 60 cm long with very good white growing points. After disinfecting with thiophanate-methyl and replanting, normal growth was restored in about half a month. From this analysis, the original owner had not fully fermented the sheep manure used on the Daxuesu; in addition, the ratio of sheep manure to the soil medium was inappropriate, which caused the fertilizer damage and death of this year's spring seedling, and the severe fertilizer damage on another spring seedling was the main factor causing economic losses. Therefore, in the process ofcultivatingorchids, we must follow the natural laws of orchid growth and must never violate its natural growth laws, artificially causing unnecessary losses. On this point, both veteran orchid friends and many new orchid friends are affected. Here I sincerely hope everyone will not make similar mistakes, so as to avoid unnecessary economic losses and psychological blows. The author is a standing director of the Yunnan Province Orchid Association and vice chairman of the Kunming City Orchid Association; advisor to the Weishan County Orchid Association in Yunnan and deputy director of the Kunming Panlong Orchid Friends Club; president and secretary-general of the Anning City Orchid Association in Yunnan Province; and editor-in-chief of the orchid journal "Xinfeng". (Yunnan, Yuan Yufang) Contact phone: 0871-8694556 (residence) (0)13608842591 Postcode: 650300 Address: Anning City People's Court, Yunnan Province