Five common orchid pests are ones that every orchid grower dreads because they would be ones to harm the plant in the long run. These insects are mostly tiny and inconspicuous, so they can’t be seen with the naked eye and can only be identified by their damage symptoms.

Unfortunately, inexperienced gardeners won’t notice most of these symptoms until the infestation is large and the bulk of the damage is done.Five Common Orchid Pests Unmasking The Orchid Enemies

This article will look at these five common pests, their symptoms, and treatment, so if you don’t want your orchids to suffer irreparable damage from these pests, dive in.

List of Five Common Orchid Pests

1. Scale InsectsScale Insects Orchid Enemy

Distinguish Characteristics
  • Tiny, tan, greenish, or dark brown oyster-shaped insects with piercing-sucking mouthparts
  • Circular, pear-shaped, wingless females without compound eyes
  • Males have compound eyes, slender, segmented bodies, wigs, and antennas
  • Powdery and white substances on different parts of orchids
  • Sticky residue called honeydew on leaves
  • Leaves turn chlorotic and begin to drop prematurely
Prevention and Control
  • Apply insecticidal soaps, pesticides, or horticultural oils if the infestation is large
  • Use a Q-tip or cotton ball dipped in rubbing alcohol to remove them
  • Spray them with an isopropyl alcohol solution
Common Species
  • Brown soft scale
  • Boisduval’s scale
  • Elongate soft scale

There are over 8000 species of scales, but only about 30 infest orchids. These insects often attach themselves to leaves, petals, pseudobulbs, and rhizomes in their adult form. They are as big as a pinhead, and would only grow three-eight of an inch when they become mature, and grow with a waxy covering on their bodies resembling fish scales, hence their name. This covering protects the insect from predators and is often dome or oval-shaped.

Scales can get on your orchids when an already-infested one is purchased and brought in contact with other healthy ones. They can also be blown onto your orchids by the wind, whether they are indoors or outdoors.

In addition to this, you must remember that there are two types of scales: Soft and armored. Soft scales are more common on orchids ad are easier to kill, while armored scales rarely infest orchids and are harder to kill due to the hard shell protecting their bodies.

Once scales invade your orchids, you will notice sticky residue on the leaves with ants around. This signifies the presence of honeydew, a sweet by-product of their feeding on the orchid nutrients, and therefore, they would also start to deteriorate the health of the plant. Their feeding also results in chlorotic lesions, allowing the plant to become stunted and die if left untreated.

Using horticultural oils or insecticidal soaps is the best way to control or treat your orchids’ scales, and this way, you will be fighting them. Insecticides can also be used, but only those specified for use on orchids.

If you detect them in their early stages, spray them with a rubbing alcohol and water solution or put a cotton swab in alcohol and apply it on them directly, and you will see them gone.

2. Fungus GnatsFungus Gnats Orchid Pest

Distinguish Characteristics
  • Small, delicate, dark, winged insects
  • Weak fliers, but walk on the orchids and growing medium
  • Slender legs and segmented antennae.
  • Yellowing, wilting, and dropping of lower leaves
  • Mosquito-like insects run around the edge of the pot
  • Tiny, black-headed maggots in the potting soil
Prevention and Control
  • Use yellow sticky cards to trap adult gnats
  • Introduce predatory mites, parasitic nematodes, and bacteria to feed on their larvae
  • Allow the potting media dry out between watering
Common Species
  • Orfelia
  • Bradysia
  • Sciardea

You probably know fungus gnats as those pesky, mosquito-looking pests that fly in your faces, trying to get in your nose and mouth, and are attracted to light. Although harmless, since they don’t bite, they can be a nuisance in large numbers. In addition, they are also one of the most common pests of orchids.

These insects are small, dark, and slender and are attracted to orchids growing in moist, degraded media. They lay their eggs in the soil and fly around the pot and the orchid, especially in cool weather, as a way to find shelter and get protected.

Their larvae are capsule-like and almost translucent with a black head, feeding on the orchid’s roots and organic matter or fungi in the growing medium, and this is also given from their name. In large numbers, their larvae can leave slime trails like that of slugs on the surface of the potting soil.

Adult gnats don’t cause severe plant damage except constituting a nuisance. Their larvae are the real threat to orchids due to their feeding, as they hatch and grow. They can cause considerable root damage and rot, causing the plant to be nutrient deficient and stunted growth. These gnats also carry pythium, a fungal pathogen that causes the termination of seeds that have grown.

An effective way to get rid of these gnats and their larvae is to use yellow sticky traps to catch the adults and let the soil become dry completely to kill the larvae and prevent further reproduction.

You can also introduce Bacillus thuringiensis var. Israelensis, which is a predatory mite, or parasitic nematodes to feed o them and their larvae. Neem oil is also effective in killing these pests.

3. Spider MitesSpider Mites Orchid Foe

Distinguish Characteristics
  • Tiny, oval-shaped, eight-legged, web-spinning mite
  • Spherical, translucent eggs that become cream-colored as they mature
  • Tiny, piercing-sucking mouthparts
  • Small, white, silky webs on the undersides of orchid leaves
  • Small white or yellow feeding spots on leaves
  • Bronzing or yellowing of foliage before they drop
Prevention and Control
  • Regular syringing to dislodge adults from the plants
  • Introduce lady beetles, predatory mites, and lacewings to feed on them and their larvae
  • Use miticides or miticidal oils and soaps
Common Species
  • Twospotted spider mite
  • Spruce spider mite
  • European red spider mite

Spider mites are also known as web-spinning mites and are more closely related to spiders due to their ability to spin silk webs. There are over a thousand species of these pests, which are less than half an inch in size, so they can’t be seen without a magnifying glass.

They have modified mouths that are characterized by having a piercing and sucking feature that would absorb the nutrients from the cells of their host, wreaking havoc as they feed.

These orchid mites feed and live on the undersides of leaves, causing them to develop yellow or white dots from their piercing. Continuous feeding will result in the silvering, stippling, or streaking of the leaves, eventually sunken and turning brown.

The leaves can also develop red or yellow discoloration before dropping, which would be clear sign for you. They may also spin small, silky, white webs on various parts of the orchid, collecting dust and making the orchid look dirty.

Spider mites don’t pose a significant threat to orchids in small numbers and are easier to eliminate. When they grow in larger numbers, you must use a miticide, insecticidal soaps, or neem oil to eliminate them.

However, you must be careful to prevent further plant damage when using such chemicals. It is always best to test the chemicals on a small part of the plant before application, to check it in a right manner.

Regularly spraying them with a strong stream of water can also help dislodge them and prevent them from finding their way back to the orchid. You can also introduce natural predators such as other predatory mites, lacewings, and lady beetles to feed on them. To prevent these mites from infesting your orchids, isolate and thoroughly inspect new orchids before introducing them to older orchid plants.

4. AphidsAphids Orchid Pests

Distinguish Characteristics
  • Small, wingless, soft-bodied, black, green, pink, brown, or colorless insects
  • Piercing sucking mouths, a pair of compound eyes, and antennae
  • Females reproduce rapidly with pregnant nymphs
  • Yellowing, wilting, and dropping of leaves
  • Presence of ants and sooty mold due to honeydew secreted by aphids
  • Distortion of flowers and buds
Prevention and Control
  • Introduce ladybugs, crab spiders, and lacewings to feed on them
  • Use insecticidal soap or horticultural oils
  • In small numbers, a steady stream of water can displace them from the orchid
Common Species
  • Bird-cherry oat aphid
  • Melon aphid
  • Russian wheat aphid

Aphids always seem to appear everywhere in the garden, and their over 4000 species can be a real problem for your plants. However, only about 250 winged and wingless species attack orchids. The two tailpipes found at the end of their abdomen can easily identify these soft-bodied, pear-shaped insects. Another distinct feature of these pests is that they shed their exoskeleton on the leaves as they mature.

Aphids have piercing-sucking mouthparts that they use to feed on the liquid nutrients from orchid tissues, causing damage to the tissues. They can infect the orchid with toxins or viruses, and some species can cause gall formation.

Like other pests that infest orchids, aphids don’t cause major harm in small numbers. You must note that when they infest in large numbers, then, you would notice that infestations are what do most of the damage, characterized by curling, twisting, yellowing, or wilting of leaves, distortion of flower buds, failure of buds and flowers to open, and stunted plant growth.

Similarly, they secrete honeydew, attracting ants and promoting the growth of black sooty mold fungus, and in short, this fungus gives the plant an unattractive appearance and also a damaged health.

These pests can be eliminated by introducing some of their predators, such as lacewings, ladybugs, and crab spiders, to feed on them and their larvae. If you catch the infestation early, spray them with a steady stream of water or alcohol solution.

In short, you can try to use some horticultural or neem oils or insecticidal soaps can be used with larger infestations. Insecticides can also be used, but only those approved for use on orchids.

5. MealybugsMealybugs Orchid Famous Invader

Distinguish Characteristics
  • Small, oval, soft-bodied, wingless insects covered in a white, cottony, waxy substance
  • Males are small and sometimes have wings resembling fluffy gnats
  • Pink, yellow, or orange nymphs without wax covering
  • Presence of ants and black sooty mold due to honeydew production
  • Chlorotic lesions on leaves that become dark
  • Leaves turn yellow and drop
Prevention and Control
  • Use a cotton wool or Q tip dipped in rubbing alcohol to pick them off
  • Apply a pesticide in large infestations
  • Use neem oil or insecticidal soaps
Common Species
  • Long-tailed mealybug
  • Pink hibiscus mealybug
  • Cotton mealybug

With just about 300 species, you will most likely find mealybugs hidden at the joints between leaves and stems, especially when your orchid’s growing area is warm and moist; where they are prone to grow and develop in such a thorough way. However, in cooler climates, they are only a problem for indoor or greenhouse plants and go through their entire life cycle of them.

These soft, oval, or elliptical insects are similar to scales and often covered in a white, fluffy, cottony wax that helps them retain moisture and protect them from heat, but their yellow nymphs are small and have no wax covering. Mealybugs feed by inserting their piercing-sucking mouths into leaf tissues and feeding on sap from the plant.

This causes yellowing or wilting of the leaves, which can eventually lead to them dropping prematurely, so you will see the orchid flower not blooming or underdeveloped. Like scales, mealybugs tend to eat more than they need and pass out the waste as honeydew, which ants feed on and promote sooty mold that turns the leaves black. In severe infestations, flower buds drop off before they can open, and the entire plant dies if not controlled early.

The most effective way to remove mealybugs is to use a pesticide suitable for orchids when the infestation is large. However, you can also control their spread by spraying neem or horticultural oils on them. In small numbers, you can use a simple cotton-tip and dip it in alcohol to pick them off.


If you’re interested in how to get rid of orchid bugs, here’s a recap of all we’ve discussed so far:

  • Orchid pests are problematic, and no gardener wishes to experience them, such as when they have issues with the pest absorbing the green sap of the leaves.
  • Test insecticides and miticides on a small portion of the plan before application to avoid damaging the orchid.
  • If you notice tiny black bugs in orchid soil, they are fungus gnats and can quickly destroy the plant.
  • Natural predators such as crab spiders, lacewings, lady beetles, and ladybugs effectively control these pests.

But after reading this piece, you should be able to identify these tests by their symptoms and effectively control and eliminate them from your orchid before they do irreparable damage.

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