As far as I know, removing the old soil as you've done is the Rx for root mealies. I would re-pot in a classic gritty mix & use a product containing imidacloprid.

I've only had experience with mealies on leaves and stems & found it too difficult to keep up with alcohol treatments on something like 3-4 dozen plants.

By the time my sick bay had more occupants than my designated 'well plant' area, I knew I had to do something drastic.

I've heard you can soak the roots in a solution of soap like Dr. Bronner's, or an insecticidal soap once the old soil is removed. However there's still the life cycle of the nasty little buggers to deal with.

My vote is for imidacloprid granules to be specific.

imidacloprid granules

Just curious six silver, how do u tell there's mealsy infestation? I can't detect any defects with the pictures u show.

Imidacloprid is the only thing I've found effective. I use it in the form of Bayer Tree & Shrub treatment.

Thank you for your replies, Hookilau, Andy!

I've already has to deal with leaf & stem mealies, once, too, and I ended up buying an insecticide when I started losing too many plants. The active component is chlorpyrifos-ethyl, which is not systemic (thank you Google); do you think it could still work against root mealies if I drench the mix with it as it comes into contact with the bugs?

I'm asking because I have no idea if the garden center will have imidacloprid insecticide (let alone, granular imidacloprid) — ordering could be complicated, given my location, so I'd like to know what are the possible alternatives...

Bernard, I took the pictures after removing the mealybugs — but here's a picture of the last little bug on the roots:

I know it's not very visible, especially as part of the white wax was stripped off when I spurted them off with water. I checked the leaves as best as I could and I'll check them again; got a few off there too. They seem fine now... I'm just concerned about future infestations and the current state of my plant...

Edit: I saw a couple more bugs on the leaves so I decided to spray the plant with the insecticide I had. Some of it got on the roots... I hope it won't kill it — though, worst case scenario, I'll be propagating leaves...

It's repotted in crushed LECA/grit mix for now. The LECA is still a little humid from yesterday, when I washed it after crushing it, to get all the dust particles off, so I haven't watered it yet...

Where are you located? Check your local garden center anyway. It's use is limited in some parts of the US & I wasn't supposed to be able to get it here on the ground in LI, but lo and behold....there it was. Imidacloprid granules, all dusty and forgotten at my least favorite because it's the MOST expensive local garden center.

Check the labels of pest control products for the active ingredients. Totally shocked me that I was able to find it here locally.

It's the only thing I've found effective. Imidacloprid is the active ingredient in Advantage Topical Flea treatment (for dogs & cats). Not sure how easy it is to get that in your area, but in a pinch, a drop of that stuff in a squirty bottle of water (working out the calculations or eyeballing it) can probably be used as a soil drench. As a matter of fact, if it were my plant, I would be more apt to just let it soak in a solution with a drop or so of Advantage/H20 solution as opposed to using as a soil drench.

Clearly this isn't the cheapest way to go, but it may be worth checking out.

this is actually what I use

Actually, my location is my greatest problem: I currently live in West Africa, Senegal; it makes finding some products difficult — perlite, turface, 3-1-2 ferts... probably systemic insecticide, too, and definitely Advantage flea treatment (I know because I have a dog and the only thing there is is Frontline Combo; only one place sells Stronghold and they're often out of stock... for months...). I may have to order if I can't find anything here; but quite a few brands don't ship to Senegal... it gets complicated, which is why I try to find local solutions...

In any case, thank you! I'll try checking different pest control products!

Edit: I came across this document (it's a downloadable PDF), wanting to know how efficient is chlorpyrifos-ethyl; apparently, I should be okay, even though it comes behing imidacloprid. Interestingly, summer oil is best. I read something about neem oil, too, somewhere...

Good luck to your plants, I saw it over the forum that someone actually heat up their soil at a certain amount of heat to kill any foreign organism in their mix before they started potting. Just a precautionary measure in future to safeguard your plants from these infestations from happening.

Unless you really trust your source and dealer you purchased from.

Thank you Hookilau! I will give this thread an update in a couple weeks, to let others who may need an alternative, if chlorpyrifos-ethyl has been entirely effective (keeping fingers crossed).

Thank you, Bernard — I hope they'll be okay, too... I thought mealies were pretty bad; now, I also have to deal with root knot nematodes on (at least) one plant (I have checked all of them yet).

Concerning soil sterilization, I started doing so a while back; but it was a little too late, I didn't do it systematically (had I known about nematodes!) and, I have to say, I got F and C degrees all mixed up, so ended up overheating it...

It's definitely time for a repot — in gritty mix.

It might be worth getting some diatomaceous earth powder and adding that to your gritty mix. It won't completely eradicate your mealy problem but it will definitely reduce it and help prevent them spreading. It's also a really good flea treatment.

It's used in poultry farming a lot so should hopefully be easy to get hold of and is pretty cheap compared to the chemical stuff.