Orchids are cultivated and grown for their breathtakingly beautiful flowers, and coaxing them into bloom can be a challenge. The time and extra attention required to maintain flowers and achieve re-bloom can end in disappointment when they drop off too soon or the buds fall off before opening.
The bloom phase of an orchid should last six to eight weeks, with some varieties supporting flowers for several months. It's completely normal for flowers to dry up and fall off, one by one, after the average expected bloom period. If this happens prematurely all at once, or when buds go soft or dry up and fall without ever developing a flower, the cause is usually a maintenance issue that can be corrected. Review your care schedule according to the following list. It may help you pinpoint what's causing your orchid to lose its blooms and buds.
Here are seven common reasons why orchid flowers fall off.
Orchids are usually classified as either cool-, intermediate- or warm-growing, depending on their temperature needs. Fluctuations between daytime and nighttime temperatures need to fall within the correct range for the specific type of orchid. Too much fluctuation is one of the biggest reasons flowers fall off early. This can also happen when temperatures rise above or fall below the acceptable range.
Check your plant's location and prepare to move it, if necessary. Placement too close to an air vent, fireplace, heater, fan, or window could be causing bloom loss.
Orchids thrive in relatively high humidity, from 40 to 70 percent. Achieving the best humidity level to support flowering can be a little tricky, so consider investing in a humidity gage. If blooms wilt and buds go soft before opening, it's likely a sign of too much humidity. When they dry out and fall, the moisture level is too low.
Humidity loss can become a problem especially in winter when supplemental heat produces dry indoor air. Try one of the following methods to improve it.
- Place a mister near your orchid. Aim the spray into the air around the plant, not directly onto it.
- Install a small humidifier near the orchid.
- Set the orchid on a tray of moist pebbles. Add water as the pebbles dry out and clean the tray regularly, but don't allow the plant's roots to sit in water.
- Add pots of ferns around the orchid. Ferns release water vapor through their leaves and can raise humidity.
How much water your orchid receives impacts both the plant and flowers to an even greater extent. Overwatering leads to soggy, mushy roots, which can result in root rot, a serious condition that can cause the plant to die if not detected and corrected quickly. Roots that lose turgidity can't conduct the nutrients needed to produce and maintain blooming.
If you suspect overwatering, remove the orchid from its pot and inspect the roots. Remove any roots that feel soft and water damaged by cutting them off at the base with a sterile blade. Apply a fungicide to the cut to prevent disease. Allow a week or two for drying out before starting a less aggressive watering schedule.
Conversely, if a root inspection reveals flat, brown, dried up roots, the orchid is being underwatered. The result is the same, with roots unable to provide enough nutrients for flowering. Remove those roots that are no longer viable and rehydrate the plant in clean water for at least ten minutes. Drain off excess and begin a more aggressive watering schedule.
Orchids need plenty of energy to create their complex flower structures. Light may be the most important factor, since it regulates photosynthesis which produces this energy. Light also affects temperature and moisture; key factors for orchid health.
Bright, indirect or filtered light provides the balance needed. Once buds have opened, providing a little more light exposure each day can sometimes extend the bloom period. If you do move your plant, keep in mind all other factors, such as temperature fluctuations, that can affect the flowers.
Insect Damage or Disease
Insects pests are usually types that damage leaves by sucking moisture from the plant. Diseased leaves and stems also strain the orchid's energy resources, which can lead to poor and even absent blooms.
Inspect your orchid regularly for any sign of pests or developing disease, isolate the infected plant and take appropriate steps to eliminate the problem immediately. Allow time for recovery before returning the orchid to its regular spot.
Most orchids are sensitive to fertilizer but will benefit from a regular schedule of added nutrients. It's important to read labels and to understand the NPK ratio when choosing the best product to feed during each phase of the plant's growth cycle. Too much fertilizer applied during bloom can produce an overabundance of salts, causing flowers to wilt and drop prematurely.
If you spot a whitish crust forming on the potting media or deposits on stems or leaves, water thoroughly several times to flush excess fertilizer. Withhold fertilizer until the bloom period is complete and start over with a dilute, mild orchid food.
Repotting at the Wrong Time
Repotting your orchid annually with fresh material helps support the nutrient level. Light, loose potting materials for orchids are depleted fairly quickly and should be replaced. Repotting during bloom stresses the plant and can lead to flower loss. Whether allowing more room for a large orchid, or just replacing spent medium, always wait to repot until the orchid has finished blooming.
Temperature Ranges. American Orchid Society
Fern Reproduction. University of Pennsylvania