How to water orchids grown on a balcony? Adjust flexibly according to temperature changes

Watering isorchidsone of the key measures determining whether cultivation succeeds or fails. "Growing orchidsis easy to grasp at a glance, but watering takes three years of skill." This saying shows the importance, flexibility and uncertainty of watering in cultivatingorchids. Many inexperiencedorchid growersare very confused about how to waterorchids. After many years of experiments, the author studied and summarized a regression equation for the dynamic correlation between watering time and air temperature for growing orchids on a south-facingbalcony. It is simple and easy to apply. After more than two years of use, it has achieved good results, and is introduced as follows. I. Basic conditions of orchid cultivation My orchid-growing site is a south-facing balcony on the fourth floor. The growing medium (self-prepared) consists of 60% leaf mold, 30% hard materials (red granules, four-in-one pond-bank soil, etc.), and 10% other materials. The orchid pots are Jianchuan clay pots (36 cm high, 22 cm pot-mouth diameter). Fertilization is carried out from mid-March to mid-October each year, using a self-developed chemical fertilizer containing 10 nutrient elements, applied once every 20 days (diluted with water at 1:1000, soaked for 30 minutes). Light duration is 1 hour after sunrise each day in spring, autumn and winter (except cloudy and rainy days), and only scattered light in summer; windows are kept open for ventilation 24 hours a day. ForA regression equation that relates watering time to air temperature dynamics is simple and easy to apply. After more than two years of use, it has produced fairly good results and is introduced below. I. Basic conditions of orchid cultivation My orchid-growing location is a south-facing balcony on the fourth floor. The growing medium (mixed by myself) consists of 60% leaf mold, 30% hard materials (red granules, four-in-one pond-base soil, etc.), and 10% other materials. The orchid pots are Jianchuan clay pots (36 cm high, 22 cm pot-mouth diameter). Fertilization is carried out from mid-March to mid-October each year, using a self-developed chemical fertilizer containing 10 nutrient elements, applied once every 20 days (diluted with water at 1:1000, soaked for 30 minutes). Light exposure is 1 hour after sunrise each day in spring, autumn, and winter (except cloudy and rainy days); in summer, only scattered light is needed. Windows are kept open for ventilation 24 hours a day. Inpest and diseasecontrol, a compound insecticide is sprayed once a month in March, April and May, which can control both red spiders and scale insects and other pests. From June to August, diseases are prevented 2-3 times according to conditions. II. Exploration of formulating the correlation between orchid watering and air temperature In December 2001, based on my many years of orchid watering data and balcony temperature records, and applying the correlation and regression relationships in statistics, the following formula was studied and summarized: Y = 32 - 0.95X + (0-5) Here Y is the watering interval in days, x is the average temperature of the orchid-growing site, and the meaning of 0-5 is: within the orchid watering interval, add 0 days on sunny days, add 1-4 days on cloudy days and during moderate rain or less, and add 5 days during heavy rain or more. Scope of application: Indoor south-facing balcony, loose, air-permeable, water-retentive compound growing medium mainly composed of leaf mold, average temperature 8°C ≦ X ≦ 26°C (the annualfour-seasontemperature variation range of my balcony). Using this regression equation, the interval between orchid waterings (soakings) can be calculated: for example, from July 20 to July 30, 20t, the balcony average temperature was 23°C, mostly sunny, then substituting into the formula gives Y = 32 - 23 x 0.95 + 0 = 10.15 ≈ 10 days, that is, watering can be done once every 10 days, soaking for 30 minutes; another example, in April 2004, the balcony average temperature was 19°C, mostly rainy, then substituting into the formula gives Y = 32 - 19 x 0.95 + (1-4) = 14 + (1-4) = 15-19 days, that is, watering can be done once every 17 days on average. The above method, after use in 2002, 2003 and from January to July 2004, achieved very good orchid-growing results. The orchids grown generally have good root systems and abundant roots, old roots do not rot, and the orchid sprouting rate is very high, with an annual sprouting rate above 1:2. Two orchid photos are attached for the editorial department's reference: this pot of orchids (LianbanSu) was divided on February 13, 2004, when it had 5 shoots. By July 20, after 5 months and 7 days of growth, it had produced 7 strong shoots, plus another 2 buds, with a total of 21 roots (18 on the front side). It is estimated that this pot of orchids can reach a total of 20 new and old shoots in a year. Traditional orchid cultivation methods mainly rely on the grower's experience. In aspects such as growing medium selection, watering, light, pesticide use, fertilizer use and ventilation, corresponding management measures are all determined based on the grower's accumulated experience. There is only qualitative orchid-growing technique, and different growers have different cultivation methods. General orchid books introduce orchid-growing knowledge and techniques that are universal and qualitative in orchid cultivation. The author is engaged in agricultural science and technology work and often conducts agricultural scientific experiments, judging everything based on the data from experimental results. From this, I thought that in orchid cultivation, quantitative, standardized, digital and operable cultivation techniques should also be studied and summarized, so as to facilitate the widespread promotion oforchidflowers and reduce the losses of beginners in orchid growing. This article is only meant to offer a modest spur to induce others to come forward with valuable contributions, hoping to attract the attention of the broad community of orchid growers and scientific and technological workers to this work. Yang Deliang (Senior Agronomist), Plant Protection and Quarantine Station of Dali Prefecture, Yunnan Province