ohugal wrote: ↑Thu Nov 30, 2023 8:51 pm
If the cactus is hibernating, a systemic isn't as effective as it could be.
Where are you located? Is your cactus in hibernation or is actively growing? What species is the cactus? If it is (severely) weakened by a mealybug infestation, I'm not sure the hot bath method is a good idea.
I would unpot the plant and remove as much soil from the roots as possible. Toss the soil in the bin and get rid of it as soon as you can. Don't recycle it. It's not worth it. I'd hose the plant down in the shower and then submerge it once or twice (7 to 10 days apart) in methylated spirits. You could also soak it in a contact insecticide. Then leave it out to dry in well ventilated spot. You can then repot it into fresh soil and a new pot. Make sure the soil is dry and not damp. If you cactus is in hibernation, don't water it until the growing season.
I'm in UK so yes, it'll be in hibernation. I'm more concerned about making sure the new cactus I've bought doesn't also get infested, and then I'll decide what to do with the infested one (throw it away or try to save it). Are you saying that any treatment shouldn't be done when it's hibernating?
I think for the new cactus I will just pot it up and see what happens rather than try any preventative measures before potting it.
Sounds like you just have above soil mealies?
I would just keep the mealy bug cactus isolated from the rest,and keep spot picking with alcohol. I use both alcohol and insecticidal soap.
Some plants are like magnets when it comes to mealies. And some they won't touch.
I believe in this situation a hot bath would do more harm than good. Just keep them under control,and next summer get it outside. lady bugs and other things will keep them at bay. Towards the end of last summer I was washing up some saucers that hadn't been anywhere near plants in months,and I found mealies underneath the rims on 3 of them. That was after I started looking. No telling how many I washed off when I wasn't looking for them.
I have a bunch of Jade plants. A lot that are cuttings from the same plant. But mealies attack some of them,and others they hardly touch. No rhyme or reason. And some that are constantly attacked seem extremely healthy.
But i think if you do a hot bath they will be back. But if they are the kind that live below the soil,that is a whole different story.
