Aphids on orchids

Aphids on orchids are a common pest that can significantly weaken the plant. These insects damage orchids by sucking sap from their tissues, thereby weakening their immunity. In this article, we will discuss how to identify aphids on orchids, what methods exist to fight them, how to treat orchids for aphids, and how to prevent their appearance.

What are aphids and how do they appear on orchids?

Aphids are small insects, only 1-3 mm in length, commonly found on houseplants, including orchids. On orchids, you may find both white aphids and other types, such as green or black aphids. However, the most common is the white aphid on orchids, which has a characteristic white or translucent body and can form large colonies on the plant.

Stages of the aphid life cycle

1. Egg stage:
   female aphids lay eggs on the underside of leaves, in leaf axils, and on flower stems. The eggs are tiny, translucent or white, and difficult to see with the naked eye. Egg development takes 4–7 days, depending on temperature and humidity.
2. Nymph (larva) stage:
   after hatching, nymphs resemble small, less pigmented versions of adult aphids. They feed on orchid sap, concentrating on young shoots, buds, and leaves. This stage lasts 5–10 days.
3. Adult stage:
   after several molts, nymphs become mature aphids. In favorable conditions (temperatures between +20…+25 °c and high humidity), aphids reach adulthood in 7–14 days. Adults can be either winged or wingless, depending on population density and the need for migration.
4. Reproduction:
   aphids reproduce both sexually and asexually (parthenogenesis). A single female can produce up to 100 offspring during her lifetime. Reproduction occurs year-round when orchids are grown indoors.

Conditions favoring aphid infestations

• High temperatures (+20…+28 °c)
• Low air humidity
• Weakened plants due to improper care
• Poor air circulation and lack of ventilation

Photos of aphids on orchids show small round or oval spots on stems, leaves, and even flowers. These insects hide on the underside of the leaves, as well as in concealed areas, such as leaf axils and flower buds. Aphids may appear as tiny white specks or clusters of small bumps.

How do aphids damage orchids?

Aphids suck the sap from orchids, leading to several problems:

1. Yellowing and wilting of leaves — damaged leaves lose moisture, which causes them to yellow and wilt.
2. Stunted growth — due to sap loss, the orchid may slow down in growth and development. Leaves become weaker, and new shoots may fail to appear.
3. Formation of sticky substances — aphids secrete honeydew, which covers the leaves, stems, and flowers of the orchid. This becomes a favorable environment for the development of sooty mold.
4. Weakened immunity — prolonged aphid attack weakens the plant's immune system, making the orchid vulnerable to other diseases and pests.

How to get rid of aphids on orchids?

To combat aphids on orchids, a comprehensive approach is necessary. It's essential to detect an infestation early and apply effective control methods.

• 1. Mechanical removal of aphids

If the infestation is not too severe, mechanical removal of aphids can be the first step. Use a soft brush, cotton pad, or sponge soaked in alcohol (such as rubbing alcohol or isopropyl alcohol). Gently wipe the affected parts of the plant, removing all visible insects. This will help reduce the number of aphids but won't solve the problem completely.

• 2. Treatment with insecticides

If aphids have spread to a larger area, you will need to use insecticides to fight them. It’s important to choose products that are safe for orchids and to follow the instructions carefully. Some effective aphid treatments include:

• Aktara — a systemic insecticide that works through the plant's tissues, killing pests that feed on its sap.
• Confidor — a broad-spectrum insecticide that helps combat aphids and other insects.
• Fitoverm — a plant-safe product that is effective against aphids and other pests.

Insecticides should be applied to all parts of the orchid, including the leaves and stems. It's essential to repeat the treatment several times at specified intervals to kill all life stages of the aphid.

• 3. Using folk remedies

For those who prefer not to use chemical products, there are several folk remedies that can also help get rid of aphids. Some popular recipes include:

• Soap solution — dissolve household soap (at least 72%) in water (1 tablespoon per 1 liter of water) and use it to spray the orchid. This solution helps remove aphids from the plant's surface and prevents their spread.
• Garlic infusion — crush 2 garlic cloves, pour 1 liter of water over them, and let it steep for 12-24 hours. Strain the solution and use it to spray the plant.
• Tobacco infusion — soak 50 grams of tobacco leaves in 1 liter of hot water, let it steep for a day, then strain and use for treatment.
• 4. Neem oil (neem oil) treatment

Neem oil is a natural insecticide and very effective against aphids. To use it, dilute 1-2 tablespoons of neem oil in 1 liter of water and treat the orchid with the solution. Neem oil helps kill not only adult aphids but also their larvae.

• 5. Repotting the orchid

If aphids have affected the orchid's roots or you suspect the soil is infected, repotting may be necessary. When repotting, carefully inspect the roots, remove any damaged parts, and wash them in a fungicide or insecticide solution. Be sure to replace the old soil with fresh, sterile soil.

• 6. What to spray the leaves of orchids with to get rid of aphids?

To effectively treat aphids, it is essential to spray the orchid leaves correctly:

• It's best to spray in the evening to avoid leaf burns caused by direct sunlight.
• Treat all parts of the plant, including the underside of the leaves, where the insects often hide.
• Repeat the treatment every 7-10 days to kill newly hatched larvae and aphid eggs.

Prevention of aphid infestation on orchids

To avoid aphid infestation in the future, follow these simple preventive measures:

1. Regularly inspect orchids — carefully check the leaves, stems, and flowers for pests, especially on the underside of the leaves.
2. Maintain optimal growing conditions for orchids — proper watering, fertilizing, and lighting will help strengthen the plant's immunity, making it less vulnerable to pests.
3. Remove damaged or old leaves — these leaves become suitable hiding places for insects.
4. Periodically treat plants preventively — using soap solutions or neem oil will help prevent aphid infestations.

Conclusion

Aphids on orchids are a serious threat to the plant’s health, but with timely intervention, it is possible to control and eliminate them. By using various treatment methods such as mechanical removal, insecticides, and folk remedies, and taking preventive measures, you can effectively get rid of aphids and keep your orchid healthy and beautiful.