Orchids provide the perfect environment for pests to live and thrive. Warm, humid air; plump, soft leaves; tender buds and blossoms; and plenty of crevices to hide under leaves and in potting media. If you aren't careful, a small bug infestation can quickly grow into a big and costly problem. Below are some photos and descriptions to help you identify what may be harming your plants as well some suggestions on how to get rid of pesky pests.
Scale are piercing, sucking insects that are difficult to control as the reproducing females are covered by a protective shell that also protects the pest's eggs. Scale is often resistant to many pesticides due to their hard outer shell.
Aphids are small, soft-bodied insects that are generally pear-shaped and green or black in color. They reproduce rapidly and are most often seen on flower buds/spikes and new growth. They produce a sticky substance referred to as honeydew which can encourage the growth of a black fungus (sooty mold). If the leaves of your plants exhibit sooty mold, it's likely that you have an aphid infestation.
Sometimes confused with scale, mealybugs are a soft-bodied insect that are readily identified at the mature stage as white to greyish-white and cotton-like. They are often found in the same areas as scale and can do substantial damage if not dealt with immediately.
Removal of Scale, Aphids and Mealybugs: Use a small toothbrush or cotton swab soaked in rubbing alcohol (known as isopropyl alcohol) to remove the pests. Do not use other forms of alcohol as they may damage your plants. Be sure to get into the crevices of the leaves as bugs tend to hide there. This treatment is a tedious process and must be repeated often. However, if you catch and treat the infestation early, it will save your plants.
These are very small, elongated insects that are most prevalent on flowers and buds. Often times, their presence is not recognized until the damage from their feeding is obvious. These bugs suck the juice right out of your plants which can cause the deformation of buds, flowers, and new growth. You may also notice browning around the edges of your flowers.
To get rid of thrips, you will need to use a pesticide. Your plants should be inspected weekly, and the pesticide should be reapplied until the infestation has disappeared completely.
Mites are microscopic arthropods that are related to ticks. They attack the undersides of leaves. Their presence is often unnoticed until it's too late. They leave behind silvery, pitted, unsightly leaves.
It is important to note that mites are not insects. Most insecticides are not effective at killing mites. You must purchase a pesticide that is specifically labeled as a miticide for use against this pest. For small infestations in the home, wiping the infested areas with a cotton ball dipped in rubbing alcohol can also be effective.
Grasshoppers, especially Lubbers, can do significant damage to orchids in a very short period of time. Lubbers are usually 1” to 3” long and can vary in color from yellow to black depending on the species and stage of growth.
These are best controlled immediately by hand or pruners.