I have heard of adding a tablespoon of vinegar to a gallon of water and watering the plants with it prior to bringing them in to rid the soil of critters. Have not heard of the spraying. I usually give them a blast of water or spray with a 50/50 mix of water and rubbing alcohol.

tj

Does water and rubbing alcohol get rid of spider mites? What about mealybugs?

Hi, D. Vinegar has its horticultural uses, primarily as an acidifier that allows hobby growers to adjust the pH of their tapwater, but I can't see how it's appropriate as a topical spray for foliage. As with many compounds that are potentially phytotoxic, the dose makes the poison. The dish detergent will continue to be used as a topical spray or root drench by those unaware of the very harmful effects it has on cuticular waxes in the leaves' dermal layer and to the lipid membranes in roots. There is just no way to support the use of dishsoaps/detergents on plant material, and saying, "I've done it for years and it never harmed my plants" isn't support - it's an anecdote that science doesn't support. If it dissolves cuticular wax and root membranes, and it's widely known that it does, it's harmful.

Al

Even the dish soap sellers aren't shameless enough to try to promote this popular yet misinformed use of their products.

I'm going to piggyback on this thread to ask some mite-control questions because other posts have left me a little confused. More details are below the questions because I know that not everyone will want to read them.

Any suggestions are welcome!

1. Can spraying with a mixture of alcohol and water ever eradicate spider mites? (it sounds like the answer is no, but hey, I don't mind asking a dumb question now and then)

2. Don't oil or soap treatments leave a film that would smother leaves? Do you have to rinse them off after treatment?

3. I hear that neem oil smells bad, which wouldn't be great in my small apartment. Does the smell go away, and if it does, how long does it take? I have a small porch, but I'm worried that the plants might be traumatized by the current nighttime lows of 45 to 55 degrees.

4. If there's nothing non-toxic to use, is there something systemic I could add to the water? I just flushed everything to get rid of salts so it will be awhile before I could do it, but the mites have been around for a while so it probably won't be a big problem.

This week I found spider mites (3 or 4 almost microscopic red spots pef leaf which wash or rub off easily) on my two ficus, two schefflera, and a dracaena, all of which live indoors. It's possible there were more mites on other parts of the plants but I didn't find them. I didn't see any leaf damage, but maybe I just didn't know what to look for. The leaves on the older ficus and schefflera plants seemed to have a sort of sticky dust on them and there were bits of web on their lower branches, which makes me think the mites have been around for a long time but weren't a problem back when they were stronger from getting better light and attention in my old, much sunnier apartment.

The dracaena looks great to me, probably because it's lived beside a window, with long shiny leaves with only a little dustiness, but the ficus and schefflera are weakened and have lost leaves from getting too little light. I've now moved everything to the window with the best light and will get supplemental lighting for the winter, but I need to do what I can to help them get as healthy as possible for repotting next June, and the mites certainly won't help.

As soon as I found the mites I started spraying daily with a mix of equal parts isopropyl alcohol and water, which has cleaned the leaves somewhat, though I haven't really hunted for mites. Now it sounds like the alcohol mixture won't actually get rid of the mites. I hear neem oil smells awful, which would be bad in my tiny apartment. I also worry that soap or oil would leave a residue that would be ugly and unhealthy for the plants. I have asthma and am prone to bad reactions to chemicals, and my ancient cat likes to chew on fallen leaves, so I really need a non-toxic treatment or something systemic that wouldn't be risky to have in the apartment.

I can't answer all of these, but neem oil does not have an offensive smell IMO. It has a distinct smell, but I suspect you could soldier through it.

Thanks, Lauren, I just assumed the info I read was right, and I won't get a chance to find some to check out myself. Where do you usually get it?

Well, the neem oil I have is a 3 in 1 neem oil, miticide (I think), and something else -icide.

i got mine at target and really love it. If you google 3 in 1 neem oil, you'll find it.

Dont Google "something else -icide" because that'll get you nowhere.

;)

Is this it?

Or this?

The only neem oil you want is cold pressed. I don't think the neem in the 3 in 1 type stuff will be as effective.

Pure cold pressed Neem oil smells kind of terrible. I don't use it for that reason.

A 50/50 mix of water and 70% isopropyl alcohol will rid the spider mites. You may need to reapply every few days for a couple weeks, but it should definitely take care of them.

Litterbuggy:. It's Gardensafe Neem Oil Extract 3 in 1. And it is a miticide and fungicide as well.

with respect, Dave, it actually is effective, quite effective in fact. Given that I am on my second bottle, I think my experiential knowledge of the product may be worth more than others' speculation.

I use it as a preventive and have only on one occasion had to use it as a treatment for spider mites. As it happens, the spider mites were on an Ivy plant that I had not treated with neem beforehand.

Dave, thanks for the comments about the alcohol treatment. I'm going to stay the course for now. The big advantage to alcohol is that I can spray liberally indoors without staining or damaging furniture, carpets, and the like, so I'll keep treating for a few weeks to make sure they're all gone. I'd better find a bigger bottle of alcohol...

Lauren, I'll write that 3-in-1 brand down in case I need to escalate things down the road.

My last spray was yesterday morning, and tonight's leaf investigation showed no adults or larvae (assuming they're not hiding somewhere clever). There are some tiny pale oblong things on some leaves, but both the larvae and adults are deep red, so they're probably cast skins or some kind of debris. It's a bit of a pain to clean the ficus, but unfortunately I don't have a garden hose to blast them clean.

Thanks for your help! I'm new around here, but I think I can safely say that these forums are awesome!

Oh, I forgot to mention : it's organic, so no chemical harm.

Another good option if you can take the plants outside for a day would be Bayer 3 in 1 insect disease and mite control.