The Cultivation Method of Rainflower
As a typical aquatic ornamental plant, rainflower is deeply loved by horticulture enthusiasts for its elegant blue-purple inflorescence and heart-shaped leaves. Although this Asian native beauty has outstanding ornamental value, it often confuses新手 gardeners due to its sensitivity to temperature and high demand for fertilizer. This article will systematically analyze the key points of scientific cultivation of rainflower from environmental regulation to disease prevention and control.
Ⅰ. Three Elements of Environmental Regulation
Temperature and Ventilation Management
Rainflower is extremely sensitive to temperature changes, with 15-30°C being the optimal growth range. When the temperature exceeds 35°C, it is recommended to open the window for ventilation for 15 minutes every hour, combined with foliar spray to cool down. In winter, it is necessary to maintain an environment above 15°C, and double glazing plus heating pad combinations can be used for insulation in northern regions.
Control of Light Intensity
This plant has typical photoperiod characteristics, and it should be ensured to receive 6 hours of direct sunlight every day during spring and autumn. In summer, a shading net (50% light transmission) should be used to filter strong light, while in winter, full sunlight can be accepted. Note: Insufficient light can lead to the stretching of the flower stem and a loose plant shape.
Water Supply Strategy
The Cultivation Method of Rainflower
As a wetland plant, rainflower needs to maintain the substrate moist for a long time. It is recommended to use the water level monitoring method: keep a 2cm shallow water layer in spring and summer, and keep the substrate moist in winter. The water quality should be tested regularly, with the EC value controlled between 0.8-1.2mS/cm.
Ⅱ. Propagation and Potting Techniques
Seed Propagation Key Points
Seed preprocessing is required for autumn sowing: first soak in 40°C warm water for 12 hours, then place in a 5°C environment for 3 days to break dormancy. Sow at a spacing of 3×3cm, with soil coverage not exceeding twice the diameter of the seed. After germination, maintain water temperature at 25°C and light intensity at 2000 lux.
Substrate Ratio Optimization
The potting substrate is recommended to use the formula 「Leaf Mold: River Mud: Perlite = 4:4:2」, with 500g of bone meal added per cubic meter. When repotting, retain 1/3 of the core soil, cut off the aging roots, and then soak and disinfect with a 1000-fold solution of carbendazim.