Orchid Bud Drop: Causes and Solutions

Why orchids drop their buds and what to do when it happens.

This condition is actually known as "orchid bud blasting," and its early symptoms are buds turning black and drying up before they drop. Orchid flower bud differentiation occurs during the maturation period of new growth and takes nearly a year to complete. Generally, after a year of nutrient accumulation, the buds emerge from the medium. Flowering periods vary among varieties. For Cymbidium goeringii, Cymbidium faberi, Cymbidium sinense, Cymbidium kanran, Chun Jian, and Lianban Lan, after the buds emerge, there is a relatively long process of growth, bud development, and vernalization. This process takes as little as five or six months, or as long as 7 months. For Sijilan and Xia Hanlan, the time from bud emergence to flowering is shorter, ranging from about 20 days at the shortest to 30 to 40 days at the longest.

Regardless of whether a variety requires vernalization, attention must be paid to fertilizer, water, and light management during both the vegetative growth and reproductive growth stages. There are many reasons why buds turn black, scorch, drop, and die, but most cases are caused by excessive humidity, over-fertilization, and poor ventilation.

Generally, flower bud differentiation indicates sufficient nutrients, so there is no need to continue applying fertilizer to the roots; foliar feeding alone is sufficient. The so-called fertilizer and water management during the flowering period is meant to promote bud enlargement and full development, which means paying attention to foliar feeding. At the same time, since temperatures are relatively high during this period and the orchid is still growing, sterilization and disinfection should be strengthened. After the buds emerge, if fertilizer and water are applied indiscriminately, combined with occasional high temperatures, muggy conditions, and poor ventilation, buds will turn black, scorch, drop, and die.

During the bud development period of orchids, from the start of autumn to before the winter solstice, phosphorus and potassium fertilizer should be applied more frequently to promote bud enlargement and full development. Whether for sterilization and disinfection or for spraying diluted fertilizer, the interval should be 7 to 10 days, and applications should not be too frequent or too concentrated. Provide adequate sunlight, otherwise the buds may be damaged and rot at the core. In addition, pay attention to water and fertilizer control before flowering. When the buds are small, withhold water once or twice, as this directly affects the quality of subsequent flowering. If you are not in a hurry to participate in an orchid show, do not deliberately adjust temperature and humidity; let the flowers open naturally.

During the vegetative growth period of new growth, apply multi-element fertilizer with nitrogen as the main component to promote robust plant growth, achieve disease and drought resistance, and ensure the conditions for flower bud growth. Therefore, whether buds can bloom normally is inseparable from earlier care.