Why Do Bougainvillea Flowers Always Fall Off?
As a common ornamental plant in southern courtyards, bougainvillea is deeply loved for its bright and beautiful flowers. However, many flower enthusiasts find that carefully maintained bougainvillea often exhibit flower drop, which not only affects the ornamental value but also reveals critical mistakes in the maintenance process. This article will systematically analyze the three major pain points in maintenance, helping you cultivate a bougainvillea with abundant flowers and lush leaves.
Misunderstanding 1: Improper Fertilization Causes Flower Drop
Imbalance in Fertilizer Ratio Issue
Excessive use of nitrogenous fertilizer stimulates the longitudinal growth of branches and leaves. Data shows that when the ratio of nitrogen to phosphorus to potassium exceeds 3:1:2, the rate of flower bud differentiation decreases by 40%. It is recommended to switch to a high-phosphorus fertilizer (such as 15-30-15) during the blooming period, and combine it with foliar application of potassium dihydrogen phosphate solution (0.2% concentration) to promote bud development.
Control of Fertilization Time
In autumn and winter, stop using solid fertilizers and switch to liquid top dressing once a month. Special cases show that applying decomposed bone meal to the plants during the flower bud differentiation period (August-September) can extend the flowering period by 15-20 days.
Misunderstanding 2: Improper Water Management
Principle of Water Control to Promote Flowering
Experimental data shows that implementing water control (maintaining soil moisture at 30%-40%) 45 days before flowering can increase the number of flowers by 2-3 times. Adopt the "dry-wet cycle" method: water thoroughly when the leaves slightly wilt, repeating 3-4 times can effectively stimulate the formation of flower buds.
Rainy Season Protective Measures
During continuous rainy periods, it is necessary to set up a rainproof shed. Accumulated water for more than 24 hours can cause root hypoxia, resulting in clusters of flowers falling off. It is recommended to use ceramic particle pads or elevate the flower box to ensure that the drainage holes are unobstructed.
Misunderstanding 3: Insufficient Light Regulation
Light Cycle Management
Bougainvillea is a short-day plant and requires 6 hours of direct sunlight daily. When the light intensity is below 30,000 lux, the synthesis of anthocyanin is hindered, resulting in dull flower color and accompanied by flower drop. It is recommended to use shade nets to regulate strong sunlight in summer, maintaining light intensity between 40,000-50,000 lux.
Light Supplement Techniques
In northern winters, it is necessary to use plant growth lights (spectral range 400-700nm) to extend daily lighting by 4 hours. Actual test data shows that the flowering amount in the light supplementation group increased by 58% compared to the control group.
By precisely controlling the three elements of water, fertilizer, and light, the problem of bougainvillea flower drop can be effectively solved. It is recommended to establish a maintenance log, recording each fertilization time, watering amount, and duration of sunlight, and adjust the plan in a timely manner based on the feedback from the plant. Mastering these scientific methods will surely make the bougainvillea bloom into a stunning annual waterfall of flowers.