Mealybugs On Pothos: The Complete Guide

You’ve found white fluff in the joint where a leaf meets the stem, and it wasn’t there last week.

That’s mealybugs, and I’ll start with the reassuring bit: your Pothos is not their first choice.

Mealybugs want something soft and juicy.

They want a Crassula.

They want a Hoya.

A Pothos is a bit tough and leathery for their tastes, which is why thrips are the pest that actually stalks this plant and mealybugs are more of an opportunist.

That said, opportunist does not mean harmless. I lost a Hoya linearis to mealybugs because I didn’t catch them in time, and by the time I did there was no plant left to save. It just came apart in my hands.

I’ve never had mealybugs on a Pothos, and I don’t think that’s luck.

I keep a lot of Hoyas, and a Hoya is a mealybug buffet.

Given a choice between something soft and sappy and something with the texture of a shopping bag, they will take the Hoya every single time, which means my Hoyas find them first and I know to go and check everything else.

If you keep succulents or Hoyas alongside your Pothos, the same is true for you, and it’s worth knowing that your fussiest plants are also your early warning system.

None of which makes a Pothos immune. It makes it second choice, and second choice still gets eaten when there’s nothing better going.

What mealybugs look like

The white fluff is the giveaway. Little cottony deposits, usually tucked into leaf joints and along stems.

The bugs themselves are soft, oval, and coated in the same white wax, roughly the size of a sesame seed. The ones you see are the females. They move, but so slowly that you’ll never catch them at it, which is deeply unsettling when you find them somewhere new.

The males are something else entirely: tiny, winged, gnat-like things that don’t feed and don’t live long. Most people never knowingly see one, and if you did you’d assume it was an unrelated fly. This is why a mealybug problem can appear in a plant on the other side of the room with no obvious route between them.

The crawlers are the newly hatched ones, and they’re minuscule. They’re also the reason this article keeps telling you to be persistent. A plant that looks clean can be carrying a generation you cannot see without a hand lens.

Is the fluff eggs or waste?

I spent years not wanting to know. Here’s the answer anyway.

It’s wax. Mealybugs secrete it to stop themselves drying out, and it also does a decent job of repelling water and sprays, which is exactly why blasting them with plain water needs repeating and why alcohol works better than you’d expect.

The bigger, fluffier cottony masses are usually egg sacs, and a single one can hold several hundred eggs.

So: mostly a raincoat, sometimes a nursery. Neither improves the experience of finding it on your plant.

Where to look

Mealybugs like tight, sheltered spots:

• Leaf axils, where the leaf stalk meets the vine. This is the number one location.
• The undersides of leaves, especially along the central vein.
• New growth and unfurling leaves.
• Under the rim of the pot and in the gap between pot and cachepot.
• Where a vine is tied to a moss pole or wrapped around itself.

If you’re checking a plant properly, go for the joints first. Skim the flat middle of a leaf and you’ll miss them.

Hang on, that one might be on your side

Before you squash everything: there is an insect whose larvae look almost exactly like an oversized mealybug, and it is there to help.

Cryptolaemus montrouzieri, known as the mealybug destroyer, is a small ladybird. Its larvae are white, waxy and fringed, and they have evolved to look like the thing they eat, which lets them wander into a colony and work through it undisturbed.

Two ways to tell them apart. Size: the destroyer larvae get noticeably bigger than a mealybug, up to about a centimetre. Speed: they move with obvious purpose, where a mealybug barely moves at all. If you see a large white waxy thing actively going somewhere, leave it alone. It’s doing your job for you.

They’re also available to buy for a serious infestation, though they need warmth to work properly, so they’re a summer option rather than a January one.

The sticky mess and the black film

Mealybugs feed on sap, and sap is mostly sugar. What goes in must come out, so they excrete a sticky substance called honeydew, which drips onto the leaves below.

Two things follow. First, everything gets tacky: the leaves, the shelf, the floor. If you’ve noticed your Pothos is inexplicably sticky, you have a sap-sucking pest, and mealybugs are a prime suspect.

Second, black sooty mould grows on the honeydew. It looks alarming, like the plant is rotting from the outside, but the mould isn’t attacking the plant at all. It’s living on the sugar. It does block light from reaching the leaf, so it’s worth wiping off with a damp cloth, but the actual fix is removing the insects producing the sugar in the first place.

Why Does My Pothos Have Black Spots?

How to get rid of them

1. Hose them off

My preferred method, and the one I’d start with. Take the plant to the sink or the shower and blast it, paying attention to the leaf joints where they’re hiding.

Physical removal works because it doesn’t care about the wax coating, doesn’t require the insect to eat anything, and cannot be adapted to. It’s also free.

The critical part is repetition. The crawlers are tiny enough to be invisible, so a single rinse always leaves survivors. Do it weekly, for a good couple of months. That sounds excessive and it is the difference between this working and not working. Most people stop after three weeks because the plant looks fine, and the plant looks fine because the next generation hasn’t grown big enough to see yet.

2. Rubbing alcohol for the ones you can see

Isopropyl alcohol at 70% on a cotton bud, dabbed directly onto each bug. It dissolves the wax coat and kills them quickly, and it’s very satisfying.

Dab the insects rather than wiping it over whole leaves, and if you do want to treat a larger area, try one leaf first and check it a day later. Pothos handle it better than most, but there’s no reason to find out the hard way.

This is a spot treatment, not a strategy. Use it on the visible colony, then go back to rinsing.

3. Soap or oil if it’s spreading

Insecticidal soap or neem oil, which kill by suffocation. A drop of oil, or even dish soap, in a one litre spray bottle. I don’t measure.

Do it in the evening, since both make leaves more prone to scorching in strong light. And again: repeat every week or so, because you’re not treating an event, you’re treating a population with staggered timing.

4. Keep the plant healthy while you do it

A stressed plant releases hormones that make it a more appealing target. Decent light and sensible watering are doing more anti-pest work than anything in a bottle, and a plant that’s thriving will shrug off a small population that would overwhelm a struggling one.

Mealybugs on the roots

There’s a version of this pest that lives underground, feeding on roots instead of leaves. You’d find them by sliding the plant out of its pot and spotting white waxy patches on the root ball or against the inside of the pot.

They’re uncommon on Pothos and I’m mentioning them mainly because they’re the one situation where repotting is the right call. Everywhere else in this silo I’ll tell you not to bother, because pests live on the plant and fresh compost achieves nothing. Root mealybugs are the exception: unpot it, rinse the roots clean, and put it into fresh soil.

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When to give up and chop

If the colony has spread across most of the plant, or you’re finding them faster than you’re removing them, stop treating and start cutting.

Cut it back to the soil. Pothos regrow from the base with real enthusiasm, the chop removes the entire population in one go, and you’re not spending the next six months looking at damaged leaves. Take a few cuttings from clean growth first if you want insurance, and check them over carefully before they go anywhere near your other plants.

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How to avoid them next time

Quarantine new plants for a couple of weeks, away from everything else. Mealybugs arrive on new arrivals more often than they arrive any other way.

Check the joints when you water. Fifteen seconds, once a week, and you catch a colony while it’s three insects rather than three hundred.

Watch your soft-leaved plants. If you keep Hoyas or succulents, they’re the ones that will get hit first, and they’ll act as an early warning for the rest of the room.

Frequently asked questions