Flower Growth and Light
This introduction to common knowledge about flower cultivation, focusing on flower growth and light, will surely be of help to you. Let's learn about it together!
Light is an indispensable condition for green plants to perform photosynthesis. Light changes with geographic latitude, altitude, terrain, and slope aspect, and also varies with seasons and day and night. In addition, the content of moisture and dust in the air, and the degree of mutual shading of plants also directly affect the intensity and nature of light. Changes in light intensity, light quality, and duration of exposure can profoundly affect the morphological structure and physiological and biochemical aspects of plants.
I. The Impact of Light Intensity on Flowers
The intensity of light often varies with geographic location, altitude, as well as cloud cover and rainfall: it decreases with increasing latitude and increases with altitude; it is strongest in summer and weakest in winter; it is strongest at noon and weakest in the morning and evening. Different light intensities not only directly affect the intensity of photosynthesis but also impact a series of morphological and anatomical changes in plants, such as the size and thickness of leaves; the thickness of stems and the length of internodes; leaf structure and the brightness of flower colors. Different types of flowers have different responses to light intensity. Most open-field herbaceous flowers grow robustly with more and larger flowers under sufficient light; whereas some flowers grow poorly in full sunlight and require semi-shaded conditions to thrive. Based on their requirements for light intensity, flowers can be divided into several categories:
(1) Sun-loving Flowers
Sun-loving flowers must grow under strong light and cannot tolerate shade. They generally require more than 70% of full sunlight; otherwise, they will not grow well. Flowers native to tropical and temperate plains, the southern slopes of plateaus, and the sunny sides of mountains are sun-loving flowers, such as most open-field annual and biennial flowers, perennial flowers, and succulents like cacti, sedums, and portulacas.
(2) Shade-loving Flowers
Shade-loving flowers require moderate shading to grow well and cannot tolerate strong direct sunlight. During the growing period, they generally require an environmental condition of 50-80% shading. In natural plant communities, they often are found in the middle or lower layers or grow in moist and shady places. Orchids, ferns, and plants from the Gesneriaceae, Bromeliaceae, Zingiberaceae, Araceae, and Begoniaceae families are shade-loving flowers. Many foliage plants also belong to this category.
(3) Shade-tolerant Flowers
Shade-tolerant flowers have requirements for light intensity between sun-loving and shade-loving flowers and have a wide range of adaptability to light. They prefer plenty of sunlight but can also tolerate some shading, such as daylilies, clematis, and platycodon.
Most flowers require about 50-70% of full sunlight, and most flowers grow poorly under 50% light. For most plants, 20000-40000Lux is sufficient for growth and flowering. In summer, the average illuminance can reach 50000Lux, and half of this is the optimal illuminance for plants. Excessive light intensity can slow down the assimilation process in plants.
The intensity of light also greatly affects the blooming time of flower buds. Flowers like the half-day flower and oxalis must bloom in strong light; evening primrose, four-o'clocks, and night-blooming cereus bloom in the evening; cattleya orchids bloom at night; morning glories bloom only in the morning. Most flowers open in the morning and close at night.
The aforementioned tips on flower growth and light (part one) for green plants and flowers are hoped to bring you help in your daily life!