Easy Ways to Eliminate Mealybugs From Indoor Plants (2024)

There are hundreds of insect species known collectively as mealybugs, nearly 300 of which are found in North America. They cause damage by sucking the juice from their host plants, especially from new growth.

In northern climates, they are principally a problem with houseplants and are found in private greenhouses but are rarely seen outdoors. In warmer climates, however, they can pose a serious problem for entire crops.

Read on for methods that will help you get rid of mealybugs outside and on houseplants.

Life Cycle of Mealybugs

The mealybug life cycle begins with a female laying eggs (anywhere from 300-600) in a cottony substance on the axils of leaves. Females die after laying the eggs. In a week to 10 days, the eggs will hatch into yellowish crawlers. Once crawlers have found a spot to feed, they progress to the various nymph stages. Female mealybugs go through three more stages, while males go through two.

During these nymph stages, mealybugs will develop the distinctive powdery white barrier that gives them their adult appearance and protects them against predators and the environment. Some mealybug species have a different number of nymphal stages, and others don’t lay eggs at all—they give birth to their young. Typically, mealybugs take anywhere from six weeks to two months to reach maturity, and many species turned into winged adults.

What Are Mealybugs?

Mealybugs are small, oval sap-sucking insects related to scale insects. These warm-weather bugs measure 1/10 to 1/4 inch and secrete a powdery wax substance as a protective coating. The mealybug's coating has a white cottony appearance, making it easy to identify when it appears on the stems and leaves of plants.

Mealybugs belong to the Pseudococcida family. Mealybugs eat plant sap. There are different types of mealybugs, with some of the most common being the citrus mealybug (Planococcus citri) and the long-tailed mealybug (Pseudococcus longispinus).

Mealybug Life Cycle

Female mealybugs lay from 300 to 600 eggs, which hatch in a few days. Within six to 10 weeks, the hatched insects are ready to lay eggs, so an infestation of mealybugs can perpetuate itself almost indefinitely unless they are eradicated.

Mealybug Damage on Plants

A light mealybug infestation is easy to get rid of, but heavy infestations can be more difficult.

• Light infestation: Light mealybug infestations are when you detect a few mealybugs and their white, cottony egg masses on the plant. The earlier you take action to get rid of the mealybugs, the less likely it will turn into a heavy infestation that will affect the plant's health. If it's a houseplant, it should be separated from other houseplants during treatments to prevent the infestation from spreading.
• Moderate to heavy infestation: Signs of a heavy infestation are lots of mealybugs and their egg masses. You'll also see their waxy excretions (known as honeydew), which encourage the growth of sooty mold fungus, and possibly ants feeding on the honeydew.Over time, mealybugs cause the leaves to yellow and eventually drop from the plant. They can also cause fruits, vegetables, and flower buds to prematurely drop off. Moderate to heavy mealybug infestations may require getting rid of the plant if it’s indoors. For outdoor plants with more serious infestations, repeated treatments are suggested.
  

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8 Ways to Get Rid of Mealybugs on Plants

Method 1: Wash Mealybugs Away

First, dislodge the mealybugs with a steady stream of water in the kitchen sink, bathtub, or shower. This is best for light infestations, as some fragile plants do not tolerate vigorous treatment. From there, repeat the treatment whenever mealybugs reappear.

Method 2: Use Isopropyl Alcohol

First, soak a cotton ball with isopropyl rubbing alcohol that contains no more than 70% alcohol. Test the alcohol on one leaf to ensure it doesn't cause damage before applying it to the whole plant. Next, wipe the mealybugs off with the cotton ball, which kills them instantly and removes them.

Repeat treatment weekly until the infestation is completely gone.

Method 3: Spray With Insecticidal Soap

When it comes to insecticidal soap, you can opt for a commercial product, preferably one that is free of perfumes and additives that might harm plants. You can also make insecticidal soap by mixing 1 teaspoon of dish soap with 1 gallon of water.

Spray the soapy solution on all the plant parts, including the underside of the leaves. Repeat biweekly or weekly if the infestation persists.

Do know, homemade insecticidal soap and many commercial products can be used up to the day of harvest on edibles (make sure to wash it thoroughly before consuming) but always check the product label.

Method 4: Use Neem Oil

Mix neem oil, which is an organic insecticide. with a mild dish detergent and water (1 to 2 tablespoons of neem oil, 1 to 2 teaspoons of dish detergent, and 1 gallon of warm water, or as directed on the product label).

Next, spray the neem oil on the plants in the morning or evening when beneficial insects are less active. The natural substance in neem oil affects an insect's feeding abilities, growth, and development, plus acts as a repellent. According to the Environmental Protection Agency, neem oil is safe to use on vegetables and other edible plants, including ornamentals.

Repeat every seven days until the infestation is gone.

Method 5: Introduce Predatory Insects

Combatting mealybugs with predatory insects will take the longest, but it is also the only one with beneficial side effects for your garden. It is not recommended if you have a severe mealybug infestation and need quick results.

Lacebugs, parasitoid wasps (Leptomastix dactylopii), and Crypts sometimes known as the "mealybug destroyer" (Cryptolaemus montrouzieri), all naturally kill mealybugs. Crypts are closely related to ladybugs and take between 5 and 6 days to hatch. All of these natural predators are more commonly used for outdoor infestations or in greenhouses.

To introduce predatory insects, plant host plants that attract them, or purchase them from commercial online retailers. Make your garden a welcoming environment for predatory insects by offering food sources and shelter. Don't use broad-spectrum pesticides.

Method 6: Use Homemade Insect Spray

To make a batch of homemade garden pesticide, combine 1 garlic bulb, 1 small onion, and 1 teaspoon of cayenne pepper in a food processor or blender and process into a paste. Mix into 1 quart of water and steep for 1 hour. From there, strain through a cheesecloth and add 1 tablespoon of liquid dish soap. Mix well.

Next, spray the solution on the plant parts where mealybugs are present, including the underside of the leaves. Repeat as needed after a few days. The mixture can be stored for up to 1 week in the refrigerator.

Method 7: Use Mealybug Traps

Pheromone traps are an effective way to get rid of mealybugs. These traps are sticky and the idea is to attract them, then trap them before they reach your plants. Place the traps in high spots such as a trellis to catch male-winged mealybugs. You can also place some on low stakes in the ground. Place traps about 10 feet apart.

Method 8: Use Synthetic Chemical Pesticide

The use of a chemical pesticide should always be the last resort and used with extreme caution. Not only do broad-spectrum insecticides indiscriminately kill all insects, good or bad, but they also contain substances that can be harmful to humans. Also, remember that the protection offered by the wax on the insects can make these pesticides less effective.

First, select a pesticide that is specifically formulated and approved for use against mealybugs, and if planning to use it on houseplants, verify that it is safe to use indoors. Follow the label directions on how and when to apply it.

If the infestation persists, follow the pesticide label instructions for repeated application.

What Causes Mealybugs?

Mealybugs tend to be drawn to certain plants that are abundant with juices they prefer to feed on. Citrus trees are particularly susceptible, and mealybugs can pose a serious threat to some commercial crops, such as mango. Mealybugs can infest various indoor houseplants, particularly tropical species.

Mealybugs are attracted to plants with high nitrogen levels and soft growth; they may appear if you overwater and over-fertilize your plants. Properly watering and feeding plants not only lowers the risk of plants getting mealybugs, it is also crucial for preventing plant diseases.

How to Prevent Mealybugs

The best control for mealybugs is defensive. Healthy, vigorous plants are less susceptible to infestation than weak, underpotted, and stressed plants.

However, mealybugs can infect even healthy plants. Often, they come in on new plants, because greenhouses are the perfect breeding ground for them. Check any new plant purchases carefully before adding them to your collection.

Many other natural strategies can help prevent mealybug infestations on your plants including:

• Reducing feeding and watering may sometimes prevent mealybugs since it reduces nitrogen levels and hardens a plant's growth.
• Wiping foliage regularly with a leaf shine solution containing neem oil.
• For plants that can tolerate such treatment, regularly spray with hard blasts of water.
• For indoor plants that can tolerate it, dropping nighttime temperatures to 60 degrees Fahrenheit will discourage mealybugs, which prefer more tropical temperatures.

If an infestation cannot be controlled after two or three weekly applications of insecticide, consider destroying the plant before the mealybugs spread to other plants in your home.

Mealybugs vs. Scale

Mealybugs are closely related to scale insects, but mealybugs are soft-bodied, rather than wearing the hard protective shells found on scale insects. Rather than the fluffy, cottony material, scale insects create a hard, barnacle-like coating on the leaves and stems of plants. The methods for getting rid of scale are very much the same as for mealybugs.