What to Do About Orchid Bud Blast? A Full Guide to Diagnosing Causes and Prevention Methods
OrchidGrowing:OrchidDiagnosing and Preventing Bud Blast
Growing orchidsThroughout the year there are really only 3 joys: plenty of new shoots in spring; plenty of flower buds in autumn; and plenty of blooms the following year. But we often find that some buds turn black, shrivel and drop as they grow. How can orchid bud blast be prevented?
Through years of practical orchid-growing observation, the author has found that flower bud differentiation in orchids occurs during the maturation period of the new shoots and lasts nearly 1 year. Generally, after a year of nutrient accumulation, the flower buds of orchids emerge from the medium. The flowering period differs among varieties:Cymbidium goeringii、Cymbidium faberi、Cymbidium sinense、Cymbidium kanran, Chun Jian,Lianbanand other orchids have a relatively long process of growth, bud development and vernalization after the buds emerge. This process takes as little as five or six months, and as long as 7 months.Four-seasonorchid, summerCymbidium kanranand others take only a short time from bud emergence to flowering, as little as about 20 days, or as long as 30 days to 40 days.
Whether or not a variety has a vernalization period, attention must be paid to the management of fertilizer, water and light during both the vegetative growth period and the reproductive growth period. There are many reasons why flower buds turn black, scorch and drop off and die; most are caused by excessive humidity, too much fertilizer, poor ventilation and similar factors. Generally, flower bud differentiation is enough to show that nutrition is sufficient, so there is no need to keep applying fertilizer to the roots; foliar feeding alone is enough. The so-called need to pay attention to fertilizer and water management during the flowering period, to promote the flower buds to swell and reach full size, means paying attention to foliar feeding. At the same time, temperatures during this period are on the high side and the orchids are still growing, so sterilization and disinfection should be strengthened. After the buds emerge, if you keep fertilizing and watering, and occasionally encounter high temperatures, muggy heat or poor ventilation, the buds will turn black, scorch and drop off and die.
During the bud development period of orchids, from the Start of Autumn to before the Winter Solstice, topdressing with phosphorus and potassium fertilizer should be strengthened to promote the flower buds to swell and reach full size. Whether for sterilization and disinfection or for spraying dilute fertilizer, the interval should be 7 days to 10 days; it must not be too frequent or too concentrated, and the plants should get appropriate sun exposure, otherwise the flower buds will be damaged and the hearts will rot. In addition, attention should be paid to controlling water and fertilizer before flowering. When the buds are small, water should be withheld once or twice, which has a direct bearing on the quality of the later bloom. If you are not in a hurry to take part in an orchid show, do not deliberately adjust the temperature and humidity; let them open naturally.
During the vegetative growth period of the new shoots, multi-element fertilizer based mainly on nitrogen should be applied to promote robust plant growth, achieve disease resistance and drought resistance, and ensure the conditions for flower bud growth. Therefore, whether the buds can flower normally is inseparable from the earlier management.