Summer Flower Care

Author: Xia Yiping
Publisher:
Publish Date: 2001-01-01
Features: This book adopts a picture-and-text format and is divided into four seasons—spring, summer, autumn, and winter—according to the blooming season or main ornamental period. It covers over 300 species. This volume introduces summer flowers. In June and July, it is the peak of summer heat, and the Yangtze River Basin experiences the rainy and humid Meiyu season, making plant care challenging. Different management measures should be taken for different species.
☆ Temperature Management — Most flowering plants thrive at temperatures between 15-25°C. Temperatures above 30°C are unfavorable for their growth and development, and many plants enter dormancy or semi-dormancy under high heat. Therefore, effective cooling is one of the key aspects of summer plant management. Cooling methods include shading, moving plants indoors, and leaf misting. For courtyard flowers or potted plants placed outdoors, shading is essential. Leaf misting is mainly used for foliage plants native to tropical and subtropical regions. However, some perennials like marigolds and bird of paradise are prone to rotting in high-heat and high-humidity conditions. For indoor plants, especially those in air-conditioned rooms, ventilation must be strengthened.
☆ Light Management — Most indoor plants cannot tolerate direct sunlight, as it may scorch leaves or cause yellowing. Generally, shading is required, reducing 50%-70% of the light exposure.
☆ Water Management — Flowering plants require significant water in summer, even drought-tolerant cacti and succulents need ample moisture for growth. Outdoor plants are typically watered once a day, while during hot seasons, they should be watered in the morning and evening. Watering is usually best done in the early morning or evening. Evening watering is beneficial because nighttime temperatures are slightly lower, promoting rapid plant growth and height. Morning watering before 10 a.m. helps prevent soil and leaf surface overheating during the day, avoiding excessive growth. For most foliage plants, the relative humidity should be maintained around 80%, so frequent leaf misting is necessary. However, excessive water in summer is not ideal. During the rainy season, it’s important to promptly drain excess water to prevent root rot.
☆ Fertilization Management — In summer, the root zone temperature of flowering plants is high, and most are in a semi-dormant state, requiring less fertilizer. Fertilization should be reduced or stopped. However, for some annuals and perennials like coleus, portulaca, coreopsis, dahlias, and cannas, which are in their most vigorous growth period of the year, light, well-composted fertilizer can be applied, but it should follow the principle of "start with less, gradually increase, and start dilute, then concentrate."
☆ Pest and Disease Control — High-heat and dry conditions in summer make plants susceptible to pests such as spider mites, red spiders, aphids, and scale insects. Spider mites can be controlled with pesticides like amitraz and acaricides. Aphids are treated with omethoate sprays, while scale insects can be manually removed. Additionally, during the hot and rainy summer months, plants are prone to fungal infections, and roses are susceptible to black spot disease. Common fungicides include carbendazim, thiophanate-methyl, mancozeb, and kocide.
☆ Propagation Work — The Meiyu season is ideal for cuttings, such as roses, hibiscus, pentas, pothos, and monstera. Plants like hydrangeas, daylilies, liriope, and dracaena can be propagated by division. If properly managed, seeds sown in June, such as marigolds, purslane, celosia, and zinnias, can bloom by autumn of the same year. For spring-blooming flowers like daisies, marigolds, and kale, seeds should be sown in August. Meanwhile, for winter-blooming flowers like cyclamen, pansies, primulas, and calceolarias, seeds should be sown in July in cool locations.