Why Won’t My Orchid Bloom?

Unless you are a fan of waxy, spathe type leaves, bulging stems and sproingy air roots, most orchid foliage will not be a particularly attractive feature. From colorful dancing butterflies to baby booties, the blooms of nearly 30,000 species of orchid represent the fine art of the plant world. The good news is that most orchids have a long bloom time of up to three months and some species will even bloom twice a year. So when your orchid has failed to bloom at least once annually, but the leaves are reproducing, have good color, and are pest and blemish free, you likely will need to adjust your maintenance schedule.

Consistent Care Is Essential

From tropical jungles, to mountain rainforests, to woodlands, orchids grow in different habitats all over the world. Learn where your orchid grows naturally and mimic the conditions of that climate as closely as possible. Orchids have the same needs as all other blooming plants, but they require a consistent care schedule. Here are some factors to consider: Temperature: Does your species of orchid require consistently warm temperatures or should you provide both a warm and cool period? Many species need cooler night time temperatures to bloom. Too much fluctuation in temperature can cause bud drop. Move the orchid to a location with more even temperatures. Humidity: This is a measurement of moisture in the air which the orchid can take up through it’s foliage and roots (in epiphytic species). If you choose an orchid of this type, misting may be required to encourage bloom. Set your mister to avoid wetting the leaves, or use a spray bottle to lightly moisturize the air surrounding the plants. Keeping your plant on a bed of moistened pebbles can also help to raise humidity. Avoid misting when your orchid is flowering. Light: Does your orchid prefer indirect light or full sun to maintain healthy foliage and bloom? Positioning your plant in a location to receive the correct type of light can make the difference in a gorgeous annual or twice yearly bloom period as opposed to uninspiring greenery. If your orchid refuses to bloom, review the plant’s natural growth and rest periods and keep it in darkness during the night. Water: Most orchids go into a period of dormancy following bloom in which their water needs are reduced. However, from the first sign of new growth (usually a new leaf) until bloom, watering requirements can differ significantly depending on orchid species. A once a week year round watering will not keep your plant in ideal condition. You will need to adjust the watering schedule to meet the specific needs of the orchid you are growing. If leaves become limp and growth at the base of the plant becomes soft, withhold water and repot the orchid with dry potting mix. Fertilizer: Orchids are heavy feeders that grow best in a slightly acidic environment with a pH between 5.5 and 6.5. Most growing media for these plants will not contain the required amount of nutrients so adding orchid food or a balanced fertilizer should be an element of routine care. Water soluble orchid food is convenient and can be added to your watering schedule as recommended. This works well since watering is usually reduced during the orchid’s dormancy period; a time in the plant’s annual cycle when fertilizer also should be withheld. Over fertilizing is not often a problem, however the recommendation for some species is to reduce the fertilizer potency by 1/4 to 1/2,

Identify and Fix Foliage Problems

Orchids, just like all other flowering plants have a bloom period. But when they are not in bloom we look to the foliage to identify and correct problems. If your maintenance schedule is consistent but your orchid is not producing new leaves or the leaves look unhealthy, you may need to tweak your maintenance schedule, or the problem may be disease or a pest infestation.

New Leaves Aren’t Growing

After bloom, most orchids will go into dormancy for a period of time during which you won’t see new growth. New growth can also slow or stop in winter during extended periods with inadequate light. During this period keep the potting mixture evenly moist, decrease water, and withhold fertilizer. This is part of the orchid’s natural growth cycle.

Leaves Turn Yellow and Fall Off

The loss of the bottom-most leaves is also a natural occurence with orchids. As new leaves form, older leaves will yellow and eventually drop. Leaves may also turn yellow with too much water or sunlight. If this is the case, move the plant to a cool place and withhold water for a few weeks.

Orchid Plant Disease

Orchids are susceptible to viruses, fungal and bacterial diseases. Viruses produce different symptoms in different orchids. Cymbidium mosaic virus causes pitting in the leaves of cattleya orchids. Other viruses cause light and dark streaks in the leaves or abnormal patterning in shades of yellow and brown. If the plant manages to bloom, the colors may be fractured and the blooms will be short-lived. If you suspect a virus, have the plant checked at an agricultural experiment station. Unfortunately there is no cure for orchid viruses. To avoid infecting other plants in your collection, dispose of the ailing plant and sterilize the pot before using it again. Bacterial and fungal infections include brown rot which starts as a light brown spot on a leaf and spreads quickly throughout the plant. Bacterial leaf spot produces sunken brown, yellow or reddish spots or streaks on leaves. These types of infections cause the leaf tissues to collapse giving a water-soaked appearance and often result from too much humidity. Water your orchids early in the day which allows the foliage to dry before night time temperatures dip. If you suspect an infection, immediately isolate the orchid, remove the diseased parts, and replace the potting medium. You can treat the cuts with a fungicide and then decrease water and humidity until the plant is recovering. Clean the pot with a solution of mild soap and water before repotting the orchid and be sure to sterilize tools to avoid spreading infection to other plants.

Orchid Pests

Insect pests include weevils, sowbugs, springtails, snails, scale, thrips, mealybugs and spider mites. Look for leaves that appear chewed, or have white powdery looking deposits on the undersides. Light infestations can usually be removed by hand or brushed off with a soap and water solution. Try neem oil, hydrogen peroxide, or isopropyl alcohol for heavy infestations. A pesticide application may be required, though, for heavy populations of microscopic insects such as thrips and spider mites.