The reverse procedure works, one of my plants that had been outside for 2-3 months was nearly ruined after a sudden spider mite attack. So it is not a bullet-proof remedy unless you have a lot of predatory mites in your area. However mites thrive in the warm, dry air indoors, so it is often better to keep the cacti outside as much as possible.

I have seen plants with mites suffer outdoors just as much as indoors.

I am not convinced so much that it is the warmth and dry indoor air that causes mites to thrive. I believe that indoor heat and low humidity cause the plant to dessicate more readily, resulting in a dehydrated plant that has a more concentrated sap. Thus, the sap is more nutritious than that of a well hydrated plant. Mites and mealies grow and breed much quicker when they are well fed and it is warm.

Outdoors, plants are healthier for many reasons: fresh air, acidic rain, ecology (predatory insects, etc.), all of which lend themselves to a reduced risk of infestation by sucking pests.

x

I live in the hot humid south and spide mites thrive outdoors here.
Tally HO!

100%%%%%%I agree with X..

Mike..:-)

so there's little hope for my bottlebrush cactus then.

i've had no luck with insecticidal soap on this plant and pesticide on others.

someone should market some predatory mites or other natural predators...

I find a lot of spiders in the house, probably because I always have the windows open, so I jar the spiders up, take them outside, and drop them on to any plants with a pest problem. It seems to help quite a bit. Spiders will attack a lot of different things.

They actually do market predatory mites..But there is no gaurentee they are going to stick around and eat the ones on your plant..A big waste of money for me.

But the insectidal soap should do the trick if you keep up on a consistent basis...

Mike..:-)

Antistress 2000 will get rid of all mites within a week.

The only problem is, since it is an anti-dessicant, it is probably not a good thing for cacti which don't benefit from water retention.

It works phenomenally on leafy plants. I had a mite outbreak a few years back on my Adenium and some Pachys. The mites were gone very quickly. I use it every once in a while as a preventive measure.

x

i'm intrigued by the predatory mites, I wonder if i bagged the plant for a few days, it would keep them in the area.

whoops I was mistaken about the pest! It's mealybugs, not spider mites.

Mealybugs are somewhat easier to eradicate. An alcohol + soap + oil spray works as long as your plant doesn't have a waxy coating or powdery bloom on it.

Or for maximum potency, use a systemic that has imidacloprid.

x

I found this thread via google and just wanted to add that taking plants outside has cured several mite infestations this year.

Just this year I've had around 8 or 9 plants infested with mites to the point of being covered in webbing. I took them outside about 2 months ago and now I'm unable to find a mite on any of them.

I live in zone 23 down in San Diego and I'm not aware of any natural predators. My yard is a bit sterile after a near-complete landscaping job. I used to get a synthetic pyrethrin treatment from Terminex but that stopped over a year ago. I haven't noticed evidence of mites anywhere else in the yard.

My only guess is the argentine ants that run my yard decided they were good to eat... other than that, I'm at a loss to explain it.

Awesome..

I would still treat your plants before you bring them inside with a good horticultural oil, such as Neem , about twice in two weeks to kill off any hiding your not aware of..You do not want an explosion out of no where come December..;-)
Just as they disappeared, they can reappear out of no where..

Mike

Neem works! I use Garden Safe Fungicide 3 in 1, which is basically neem, and inspect (with magnifing glass) and spray when necessary on eriosyce and copiopa.

I always had problems in the winter with mites, but last fall decided to hit all my plants with imidacloprid spray 2x about a week apart and never had a mite all winter......needless to say I will be repeating that again this fall :o) Dan

odd for Imidacloprid to work as it is a strict insecticide and has no activity against arachnids whatsoever... maybe the carrier killed the mites? Mites do indeed seem to attack my favorite plants (palms) in low wind situations. My greenhouse is VERY humid and the plants are far from dessicated, but the mites still attack. My friends with more intelligently built greenhouses have large fans going all the time and that greatly reduces the spidermite problem. As for killing them, just about any product seems to work, so I use the safer ones. Gotta hit the leaves from all sides, though (most mites live on the leave's underside, where it is harder to spray). And once the damage is done, it stays that way, so you have to wait for the new leaves before the plant looks good again. No personal experience with mites on cacti... so can't comment there.