1
White cottony fluff in the leaf joints.
Soft, and it squashes wet and sticky.
Mealybugs
White fluff in the leaf joints?
Know for sure. Then meet the beetle that dresses like them.
Check that it's mealybugsIs it mealybugs?
Squash it. Mealybugs leave it sticky.
2
The ones on the leaves are explorers.
Not all of them. The rest hide in leaf joints, under leaves and on the roots.
The easiest check? Look in the leaf joints and under the leaves. Root mealybugs show as wilting in moist soil, with white wax on the roots or inside the pot.
Not quite matching?
White, but not mealybugs?
Cryptolaemus larvae
Released crypts already? Bigger, up to half an inch, with long wax strands. Those are yours.
Fungus gnats
Tiny pale fliers near a colony with two white tail threads are male mealybugs. Fungus gnats are darker and stay by the soil.
Meet the mealybugs
A soft bug in a wax coat.
Wax, wings and a beetle in disguise.
Mealybugs are small, oval, segmented insects dusted in white wax. The young start out bare and quick, then settle and grow their coat.
What it eats
They drink sap and drip sugar.
Mealybugs suck sap, which weakens the plant. The sticky waste, honeydew, lands on the leaves below, and black sooty mold grows on it.
Where it lives
Females stay put. Males go visiting.
Four places to look on one plant.
Leaf joints and stemsColonies and egg sacs.
Tucked where a leaf meets the stem.
Under the leavesOut of sight from above.
In the airOnly the males fly.
Off to females on other plants.
On the rootsRoot mealybugs.
They live in the soil, out of sight.
Karen's noteKaren Horn, owner
No plant is too isolated. The males fly.
The life cycle
Egg to egg-layer in four to six weeks.
In a warm room. The generations overlap.
Week 1Egg
In a cottony sac that sheds water.
Weeks 1–2Crawler
Tiny, pale and quick. Spreads before it grows any wax.
Weeks 2–5Nymph
Settled, and building its coat.
Week 5 onAdult female
Wingless and fully waxed. Stays put.
Week 5 onAdult male
Winged and gnat-like, with two long tail threads. Never feeds, and lives a day or two.
Swipe for the next stage →
How fast they multiply
100–200
eggs in one cottony sac.
One white tuft is a nursery.
She fills it over 10 to 20 days, so eggs, crawlers and adults share one cluster.
Karen's noteKaren Horn, owner
Every stage, all year. Your living room has no winter.
Why sprays miss
Their wax is a raincoat.
The waxy coat, and a habit of hiding in tight spots, keep contact sprays off them. The sac keeps the eggs dry, so the colony comes back.
A different kind
The long-tailed one skips the egg sac.
Long-tailed mealybug keeps her eggs inside her until they hatch, and trails two tail threads longer than her body. The beetles eat it but can't breed on it.
What to get
The size of the colony picks the size.
Question 1 of 2
Where are they, and how spread out?
Question 2 of 2
How many plants?
Count them all, not just the ones with damage.Our pick for you
Cryptolaemus larvae
Cryptolaemus larvae can't fly, so they stay on the plant you put them on and feed until the colony is gone, egg sacs included.
See Cryptolaemus larvaeOur pick for you
Cryptolaemus adults
Cryptolaemus adults fly, so they find colonies you haven't spotted, and the females lay their eggs right inside them. Serious infestation? Add larvae to the worst clusters too.
See Cryptolaemus adultsOur pick for you
Soil mites (Stratiolaelaps)
Root mealybugs live below where Cryptolaemus hunts. Stratiolaelaps scimitus is a soil mite you top-dress onto the pot, and it works the root zone. Mealybugs on the stems too? Run both in the same pot.
See Soil mites (Stratiolaelaps)See all picks
| If you see | Our pick | Why |
|---|---|---|
| Clusters on a few plantsWhite tufts in the leaf joints of one or a few plants |  Cryptolaemus larvae |
Cryptolaemus larvae can't fly, so they stay on the plant you put them on and feed until the colony is gone, egg sacs included. |
| A whole collection or greenhouseColonies scattered across many plants | Cryptolaemus adults |
Cryptolaemus adults fly, so they find colonies you haven't spotted, and the females lay their eggs right inside them. |
| Wilting, with white on the rootsThe plant droops in moist soil, with wax on the roots when you unpot |  Soil mites (Stratiolaelaps) |
Root mealybugs live below where Cryptolaemus hunts. |
What the beetles like. A warm room, 64–90°F, since cool rooms slow them and adults may fly off. Bright light, unusual for a predator; adults are busiest on sunny days. And a real colony: adults leave a plant with too little to eat, and larvae can't.
Our suggested plan
Two weeks, then check the joints.
- 1
Release day
Cryptolaemus larvae on the plants with mealybugs.
Ants dealt with first. Evening, right at the colonies.
- 2
About 2 weeks
Check the leaf joints.
Release again if mealybugs are still there.
- ✓
Stop
No new colonies two weeks in a row.
For a typical infestation. Every other week or monthly is usually fine. A light one may need less. A heavy one may need adults and larvae together. Long-tailed mealybug needs repeat releases. Adjust to what you see, or ask us.
How to release
Ants out. Beetles in.
Before you order
Confirm it's mealybugs. Squashes wet and sticky. Already confirmed above.
While it ships
Wait out any spray.
Once dryNeem
1 dayInsecticidal soap
8–12 weeksSynthetic pyrethroids
Something else? Send us its active ingredient. If the label says longer, the label wins.
Baits or sticky barriers, two or three days before release. Ants farm mealybugs for their honeydew and go after your predators.
Release day
The same day they arrive, in the evening, right at the colony.
The beetles are often thirsty after shipping.
Tip the tube, hulls and all, at the base of the plant. They crawl up. Don't squeeze them.
Open the container by them in the evening. Skip the white shirt; they land on light colors.
About a teaspoon at each stem. Don't water them in.
After
Leave the white larvae alone. Bigger, with long wax strands. Those are yours.
Karen's noteKaren Horn, owner
The white fluffy things in the box are your predators. Don't squash them.
What to expect
Colonies thin from where you released.
- Right after release
Larvae take a day or two to reach the mealybugs. Adults may wander before they settle.
- As it takes hold
Colonies thin, starting where you released. New white, waxy larvae appear. They're yours.
- When it's working
No new colonies. Old sooty mold and damage stay.
Still finding colonies at two weeks? Go again. None two weeks in a row? You can stop.
Karen's noteKaren Horn, owner
Larvae disappeared? They're pupating on the stems. Beetles later.
Why treatment fails
Usually ants. Sometimes a wipe.
1
Ants left on the plant.
The one step you can't skip. Bait or barrier first.
2
The larvae got wiped off.
White fluff after release is often your own larvae. Go by size and wax.
3
Too few for the colony.
Buy the size for the number of infested plants.
Prevention
They arrive on a new plant.
Mealybugs almost always arrive on a new plant or cutting. Check its leaf joints and stems before it joins the others, and keep it apart for a couple of weeks.
The beetles are for colonies you can see, not insurance.
Karen's noteKaren Horn, owner
Reusing a pot? Check it. Mealybugs love a hand-me-down.
Often shows up with
Scale is the neighbor.
Soft scale
Squashes wet and leaves honeydew too. The mealybug destroyer takes its crawlers.
Questions
Mealybugs, asked and answered.
Are mealybug destroyers safe around kids and pets?
Yes. Cryptolaemus montrouzieri is safe around people, pets, plants and food crops. The beetles are strictly carnivorous, don't eat leaves, roots or fruit, and leave no residue.
How many releases will I need?
Where the beetles can breed, one release often does it: they need mealybugs to reproduce, and a real colony is a nursery for them. Long-tailed mealybug is the exception. It bears live young and makes no egg sac, so the beetles eat it but can't breed on it, and repeat releases are the plan.
Why did the adults fly away?
Adults fly to find food. If there aren't enough mealybugs to keep them busy, or the room is cool, they move on. A generous release onto a real colony keeps them where you put them. For a small, isolated problem, larvae are the better choice because they can't leave.
Do they work on root mealybugs?
No. Cryptolaemus hunts on stems and leaves and doesn't go below the soil line. If a plant wilts in moist soil and you find white wax on the roots or the inside of the pot, pair it with a soil predator: Stratiolaelaps scimitus or beneficial nematodes. Both can work in the same pot.
Can I use neem or other sprays with them?
Not while the beetles are out. Before release, neem is done once it's dry and insecticidal soap needs a day. Synthetic pyrethroids need 8 to 12 weeks. Residue can harm the beetles or cover up the scent of the mealybugs they hunt by.