Mealy Bugs: How To Get Rid Of Mealybugs [CONTROL GUIDE]

Most people want to know one thing: how do you get rid of mealybugs?

They usually ask after spotting small, white, cottony clumps on an indoor plant or on an ornamental plant in the landscape. If the fluff sits where leaves meet stems and the leaves feel sticky, mealybugs are a likely suspect.

Here’s the honest part first. The University of California Statewide IPM Program (UC IPM) says mealybugs are very difficult to manage with insecticides.

The good news? Caught early, a small infestation on a houseplant is very manageable with patient, simple steps. Let’s walk through what works, what to skip, and when to let a plant go.

What Do Mealybugs Look Like?

Mealybugs are soft, oval insects covered in white wax. UC IPM says most adults are wingless females with segmented bodies; males have wings but are rarely seen. Missouri Botanical Garden says a typical female is 1/16 to 1/8 inch long, and some species reach 1/4 inch.

They are piercing-sucking insects, close relatives of plant scale bugs. Missouri Botanical Garden places them in the order Hemiptera, along with scales, whiteflies and aphids.

UC IPM says they usually feed in colonies in protected spots: the crown of a plant, branch crotches, stems near the soil, and between a stem and the leaves touching it. A few species feed on roots.

Not every white, waxy speck is a mealybug. UC IPM says they can be confused with cottony cushion scale, woolly aphids, soft scales and whiteflies, so look closely at the insect under the wax.

UC IPM lists these among the most common pest mealybugs:

• Citrus mealybug (Planococcus citri), the most common mealybug on indoor ornamentals
• Longtailed mealybug (Pseudococcus longispinus), which gives birth to live young instead of laying egg masses
• Obscure mealybug (Pseudococcus affinis)
• Grape mealybug (Pseudococcus maritimus)
• Vine mealybug (Planococcus ficus)
• Ground mealybugs (Rhizoecus species), which live in the soil and feed on roots

UC IPM also mentions the pink hibiscus mealybug (Maconellicoccus hirsutus), whose saliva is especially toxic to plants. The UF/IFAS Extension Charlotte County office adds that Florida has many mealybug species, with names like pink hibiscus, pineapple, citrus, papaya and coconut.

What Damage Do Mealybugs Cause?

Mealybugs suck sap, which weakens the plant. UC IPM says high populations can slow growth and cause leaf drop.

Missouri Botanical Garden says heavily infested plants can show irregular or no growth, yellowed leaves and significant leaf drop, and that left untreated, plants can die. The UF/IFAS Charlotte County article adds that mealybugs inject chemicals that cause distortion, stunting and yellowing.

They also excrete sticky honeydew, which can make leaves and floors sticky. A black fungus called sooty mold grows on the honeydew. UF/IFAS Gardening Solutions says sooty mold doesn’t injure a plant directly, but it blocks sunlight from leaves, reducing photosynthesis.

The upside: UC IPM says healthy plants can tolerate low populations without significant damage. Catch them early and you have plenty of options.

Watch for Ants on the Honeydew

Ants crawling up and down a plant are a clue worth following. UC IPM lists ants feeding on honeydew as a sign of mealybugs, and says ants protect mealybugs from their natural enemies. Missouri Botanical Garden adds that ants may carry mealybugs from one plant to another.

How Fast Mealybugs Multiply

Life cycles vary by species and temperature. UC IPM says adult females of most species lay 100 to 200 or more eggs in cottony egg sacs over 10 to 20 days.

The University of Wisconsin-Madison Extension says citrus mealybug females lay up to 600 eggs, and Missouri Botanical Garden says eggs hatch in 1 to 2 weeks and females reach adulthood in about a month.

Newly hatched mealybugs, called crawlers, have no wax and move around, but UC IPM says they soon settle down to feed and start making their waxy coat.

UC IPM also says all stages may be present indoors year-round, and indoor plants are especially vulnerable because mild temperatures favor mealybugs and indoor plants usually aren’t exposed to the natural enemies that keep them in check outdoors.

Mealybugs on Houseplants: Which Plants Get Them Most?

Colorado State University Extension lists these houseplants as the ones most commonly affected:

• African violets (ground mealybugs on the roots are a particular problem, per UC IPM)
• Aglaonema
• Dieffenbachia
• Some dracaenas
• Most ferns
• Ficus
• Jade plant
• Norfolk Island pine
• Some palms
• Philodendron
• Pothos
• Schefflera
• Streptocarpus
• Yucca, including the spineless yucca

UC IPM’s own houseplant list adds coleus, cactus, hoya, orchids, poinsettia and herbs such as rosemary and sage. For more on these, see our guides to cactus mealybugs and succulent mealybugs.

Beyond houseplants, UC IPM names citrus, grapes, bird of paradise, cactus, coral bells, cypress, fuchsia, hibiscus and mimosa among the most commonly infested plants.

It also names figs, flax grasses (Phormium), gardenia, jasmine, Miscanthus grasses and oleander among the woody and perennial plants mealybugs attack. Among fruit trees, citrus has the most problems.

How To Get Rid of Mealybugs

UC IPM is blunt: their waxy coating repels most contact insecticides, and their habit of hiding in tight spots makes them hard to reach. So the best plan combines several steps, starting with the gentlest.

Start With Prevention

UC IPM says mealybugs are often brought in on new plants, tools or pots. Missouri Botanical Garden recommends examining, quarantining for 2 or 3 weeks, and treating as needed all new plants before placing them near mealybug-free plants. UC IPM says if you can’t remove all the mealybugs from a new plant, discard it or take it back to the source.

Once you’ve found mealybugs, UC IPM says to keep checking plants, pots and stakes on a regular basis and to dispose of infested items. Go easy on fertilizer, too: UC IPM says high rates of nitrogen combined with regular irrigation may stimulate tender new growth as well as mealybug egg production.

Hand Removal and a Water Spray

For a houseplant, UC IPM’s first step is to hand pick the mealybugs or prune them out. On sturdy plants, it says a forceful spray of water can reduce exposed populations, repeated every few days as needed.

The Wisconsin Extension suggests a moderately strong spray of warm water, and says to dispose of pruned cuttings right away, because mealybugs can survive on detached plant parts as long as those parts stay moist.

Missouri Botanical Garden says manual removal is unlikely to eliminate mealybugs, but it can often keep an infestation within tolerable limits without harming beneficial insects.

Rubbing Alcohol: The Right Way

As with soft scale insects, alcohol on a cotton swab is a popular spot treatment. For small infestations on houseplants, UC IPM says a 70% or less solution of isopropyl (rubbing) alcohol in water may be dabbed directly on mealybugs with a cotton swab to kill or remove them.

Test the solution on a small part of the plant 1 to 2 days beforehand to make sure it doesn’t cause leaf burn. UC IPM adds that in some cases a much more diluted solution may be advisable.

Where infestations are extensive, UC IPM says a 10-25% solution of isopropyl alcohol can be applied with a spray bottle, repeated every week until the infestation is gone.

Colorado State University Extension gives a similar option: a mix of 10 percent rubbing alcohol and 90 percent water sprayed directly onto the insects, repeated weekly, after testing on a small part of the plant. Our step-by-step guide covers killing mealybugs with alcohol.

Not every extension service is comfortable with alcohol on leaves. UF/IFAS Gardening Solutions lists vinegar and alcohol as phytotoxic ingredients that cause leaf burn and says they should not be applied to plant tissues.

That’s one more reason to test a small area first and stop if you see damage. The Wisconsin Extension notes it may take a day or two for symptoms to show.

Skip the Dish Soap and Kitchen Recipes

You’ll find plenty of homemade sprays online that mix alcohol, dish soap and even neem oil. UF/IFAS advises against them.

It says dish “soaps” are really detergents designed to be powerful cleaners, and even watered down they can cut through the waxy layer that protects leaves, often leaving damaged, dry, crispy leaves.

UF/IFAS also warns that mixing different products in home recipes is dangerous, because common cleaners that are safe on their own can be toxic to people when used together.

UC IPM’s statement on homemade pesticides says homemade mixtures generally haven’t been tested in replicated research trials, and that when UC IPM mentions oils and soaps it means products formulated for use as pesticides, not household soaps and oils.

Insecticidal Soap, Horticultural Oil and Neem Oil

UC IPM says insecticidal soaps, horticultural oil or neem oil insecticides applied directly on mealybugs can provide some suppression, especially against younger nymphs that have less wax. Test them on part of the plant first, just as with alcohol.

Missouri Botanical Garden suggests treating when crawlers are present, spraying thoroughly because mealybugs hide under leaves and in crotches, and repeating applications as the label directs.

The UF/IFAS Charlotte County article recommends spot treating with insecticidal soap or horticultural oil as per label directions, and not in the heat of the day, since it can burn the leaves.

Buy a product registered as an insecticidal soap rather than using a dish detergent. UF/IFAS says properly registered insecticidal soaps are usually only 1-2% soap by volume, and that plants under drought stress, in excessive humidity or in heat above 90°F should never be treated with soaps. Mixing rates differ from product to product, so follow the label on the one you buy.

Neem oil comes from the seeds of the neem tree and is sold at garden centers. It is a pesticide, so treat it like one.

The National Pesticide Information Center (NPIC) says neem oil can be slightly irritating to the eyes and skin, is slightly toxic to fish, and its azadirachtin component is moderately toxic to fish and other aquatic animals. NPIC also reports adverse reactions, some fatal, in cats treated with neem oil for fleas in other countries.

Don’t count on neem lasting long on the leaves, either. NPIC says azadirachtin breaks down quickly on plant leaves, with a half-life of 1 to 2.5 days. See our guides to neem oil on mealybugs, neem oil for plants and applying neem oil, which explains why the label rate on your bottle comes first. Neem is also used to clean plant leaves.

Whatever you use, read the pesticide label and wear the appropriate safety equipment it calls for.

Systemic and Other Insecticides

UC IPM says plant spikes or granules containing the systemic insecticide imidacloprid may reduce mealybug crawler numbers on houseplants.

It also says these neonicotinoid products are less reliable against mealybugs than against other piercing-sucking insects, and their use should be avoided when possible, especially on flowering plants, because of potential harm to natural enemies and pollinators.

Sources differ on the sprays. Colorado State University Extension says pyrethroid sprays are usually effective for mealybug control, and Missouri Botanical Garden lists acephate, bifenthrin and pyrethrins as effective. UC IPM says pyrethroids may not be much more effective than soaps and oils and can be devastating to natural enemies.

Missouri Botanical Garden says to always follow the product’s label and make sure the product is effective against mealybugs, and that not following the pesticide label is a violation of federal law.

Natural Enemies: Mostly an Outdoor Option

Outdoors, natural enemies do a lot of the work. UC IPM lists parasitic wasps, lady beetles, green and brown lacewings, spiders, minute pirate bugs and predaceous midge larvae.

It names the mealybug destroyer lady beetle, Cryptolaemus montrouzieri, as the most important of these predators in many areas. Another option, the parasitic wasp Leptomastix dactylopii, is sold for greenhouses, citrus groves and interiorscapes, but UC IPM says it kills only the citrus mealybug.

For a houseplant, buying predators is less practical. The Wisconsin Extension says most natural e

nemies are not appropriate for use in the typical home. UC IPM says there is little point in releasing mealybug destroyers when mealybug numbers are low or not reproducing, because the beetles need mealybug eggs to reproduce. More ideas are in our guide to natural mealybug control.

If your plants grow outdoors, protect those natural enemies: UC IPM says to avoid broad-spectrum insecticides and keep ants out of infested plants.

Know When To Let a Plant Go

UC IPM says none of the available insecticides will likely provide complete control, so plan to monitor and treat again as needed. When infestations become severe, it suggests discarding houseplants rather than repeatedly treating them with insecticides. The Wisconsin Extension agrees, and says root infestations are particularly difficult to control, so replacing the plant is often the most practical fix.

Mealybug Treatment on Orchids

UC IPM names orchids among the houseplants that often have mealybug problems. On orchids, look in the leaf joints, under leaves, on buds and in crevices of the pot.

The American Orchid Society (AOS) takes a different view of alcohol than UC IPM does. It says spray-on contact insecticides such as insecticidal soap and horticultural oil are the most effective control, along with crushing mealybugs with a cotton swab, and that alcohol is not very effective against mealybugs and can strip away the plant’s waxy cuticle.

AOS recommends disturbing the colony first by wiping away the mealy powder or washing the bugs off, then following up with insecticidal soap, and says 3 to 4 applications at intervals of a few days typically do the trick indoors.

If you use alcohol on an orchid anyway, stick to UC IPM’s 70% or less dab and test a small spot first.

Where Orchid Mealybugs Come From

Prevention is the best treatment. Mealybugs usually arrive on:

• New plants added to your collection (UC IPM)
• Plants that spent the warm months outdoors (Missouri Botanical Garden says plants summered outdoors can be attacked)
• Ants carrying them from plant to plant (Missouri Botanical Garden)
• Pots, tools and stakes from infested plants (UC IPM)

Inspect and quarantine every new orchid before it joins the collection. If mealybugs are on buds or flowers, UC IPM’s advice to prune them out applies: losing a bloom spike beats losing the plant. Also see how to get rid of mealybugs on fiddle leaf fig.

How To Get Rid of Mealybugs on Succulents

You’ll see advice online to spray succulents with straight rubbing alcohol, or even pour it on the soil as a drench.

Neither UC IPM nor UF/IFAS recommends that. UC IPM’s limit is 70% or less, dabbed on with a swab after a test on a small part of the plant, and 10-25% for a spray. UF/IFAS lists alcohol as phytotoxic and says it should not be applied to plant tissues.

For succulents, Iowa State University Extension says to look for cottony masses along leaf veins and where leaves and stems join, isolate the plant, rinse the foliage and physically remove the masses.

It says neem and insecticidal soap can be used as instructed on the label, that most infestations take multiple applications, and that a severe infestation that can’t be controlled means discarding the plant to protect nearby plants.

Look below the soil line, too. The Wisconsin Extension says small white cottony masses around the drainage holes of a pot point to root mealybugs, which often can only be confirmed by sliding the root ball out.

UC IPM says ground mealybugs are even more difficult to control than those feeding above ground, so dispose of infested plants quickly before the pests move to clean ones. For more, read our guide to mealybugs on succulents and what the fuzzy white bugs on plants are.

If you grow succulents outdoors, encourage natural predators such as lady bugs, which UC IPM lists among the natural enemies of mealybugs.

Keep a Clean Plant Area

Mealybugs hide in the gear around your plants as well as on them. UC IPM says to check pots, stakes and other materials for mealybugs and their egg sacs and to dispose of infested items. It also suggests tossing older “grandmother” plants that may be a source of infestation for new plants.

Check the bottoms of containers and saucers when you inspect, and keep infested plants from touching others: the Wisconsin Extension says mealybugs can easily crawl from one plant to another where leaves or branches overlap.

Vigilance Is Key

Catch mealybugs before they have a chance to build up, and the gentle methods have their best shot. The Wisconsin Extension says washing rarely gets every mealybug, so check plants periodically and treat again when more show up. Keep looking under leaves, in leaf joints and around new growth every time you water.

Got a mealybug fix that worked for you? Tell us in the comments.

Recommended Reading

• Are Mealybugs Harmful To Humans?
• 6 Home Remedies For Controlling Mealybugs