I've just found out that my Ipomea purga/jalapa is covered in spider mites - the bad kind that make webs, not the nice red predatory ones. It is on a windowsill with a newly bought Gymnocalycium (probably baldianum - probably bought too recently, as in a few days ago, to be the source of the infestation), Lophophora williamsii, Adromischus clavifolius, Graptopetalum amethystinum, Pachyphytum oviferum, and a Pachyveria.
I have taken the Ipomea outside and sprayed liberally with Bug Clear Ultra, along with the Adromischus which lives closest to it, and put them both in quarantine in the garage. I'm guessing it would be best to spray everyone else as well, even though I can't see any mites on them? Are any of them sensitive to the spray?
Spider Mite Advice
Re: Spider Mite Advice
Spider mites are everywhere. They just show up whenever the conditions are right. I wouldn't worry too much about spraying everything. You aren't going to eradicate the mites and it has little preventative value, possibly worse than useless if it kills predators. Have a close look though, and see if the mites are on anything else.
Bug Clear Ultra is pretty safe on most succulents, but watch out for it washing off any blue or grey coatings on the leaves. Not the first choice for mites though, even though they are listed on the label. Although you don't have a lot of (legal) choices left, you could just pick up a cheap Pyrethroid spray and use it at the first sign of mites, then regularly every week or two until they seem to be gone. You could also alternate the two although technically you're not supposed to use Bug Clear Ultra more than four (?) times a year. Simple soap sprays are pretty much as effective against the mites, but are much more likely to cause a phytotoxic reaction. More expensive and effective alternatives are available on the black market (aka eBay), but not worth the money unless you are growing pot or the mites are chewing up a lot of expensive succulents.
Bug Clear Ultra is pretty safe on most succulents, but watch out for it washing off any blue or grey coatings on the leaves. Not the first choice for mites though, even though they are listed on the label. Although you don't have a lot of (legal) choices left, you could just pick up a cheap Pyrethroid spray and use it at the first sign of mites, then regularly every week or two until they seem to be gone. You could also alternate the two although technically you're not supposed to use Bug Clear Ultra more than four (?) times a year. Simple soap sprays are pretty much as effective against the mites, but are much more likely to cause a phytotoxic reaction. More expensive and effective alternatives are available on the black market (aka eBay), but not worth the money unless you are growing pot or the mites are chewing up a lot of expensive succulents.
--ian
Re: Spider Mite Advice
Thanks 
The Bug Clear seems to have killed the mites, but I'm keeping it quaratined for now. I'll also keep an eye on the other plants, I'm actually glad that I don't have to spray them!
The Bug Clear seems to have killed the mites, but I'm keeping it quaratined for now. I'll also keep an eye on the other plants, I'm actually glad that I don't have to spray them!
Re: Spider Mite Advice
You haven't killed any eggs, so you'll almost certainly need to spray again. Watch out in a week or two for more mites. They breed faster if it is warm. They struggle if it is too humid, windy, the temperatures vary a lot, or just about anything really. Plants outdoors are much less likely to be infested.
--ian