Spider Mites - Orchid Board

Kevstar · #1 09-19-2018, 05:36 AM

Hi guys,

This is more of a general question really as I currently don't have spider mites thankfully!

I've been watching a lot of videos and seen that some people recommend using a light oil to treat spider mites.

So my question is, do you literally spray it over the entire plant including leaves? It just seems to go against the effort we put into trying to keep liquid out of the crown and between the leaves etc.. wouldn't it cause either crown or stem rot?

As I said, I don't have spider mites but it would be good to be prepared for the future..

Thanks,

Kev

estación seca · #2 09-19-2018, 01:20 PM

Spider mites are so common in gardening settings, it is safe to believe they will always come back. In many areas of the world, like here, they live outside. They are most prevalent with warm temperatures and low humidity, so watch for them during periods of such weather.

My approach is to control them, since I can't eliminate them.

This means regular inspection of plants for signs of infestation, and prompt treatment. Oil, 70% alcohol and even sprayed water may be used. The first two kill mites, and the water knocks them off the plant; they are unable to walk far enough to get back on the plant.

I don't use oil, since it's messier than the alternatives.

Roberta · #3 09-19-2018, 02:00 PM

Horticultural oils are only effective on leaves. They work by smothering insects, mites, etc. No worries here about water in crown (which is an over-rated hazard at any rate) Just don't spray the stuff when the plant will be receiving direct sun. (So early morning is best, no direct sun and any excess water will evaporate before the cool of evening. How effective it is? I don't know that it does much more than soapy water which does the same thing - "contact" treatments all have to be repeated every 5 days or so for several weeks to be effective, to kill successive generations.

Kevstar · #4 09-19-2018, 02:05 PM

Thanks guys. Good to know!

camille1585 · #5 09-19-2018, 02:40 PM

I've never used any sort of oil for pests (yet), but have had success against spider mites using 70% alcohol. I pour some on a cotton pad and wipe down each leaf, treating 3 times at one week intervals. It's a bit tedious to do if it's plants with many smaller leaves (like Dens) but if only a few plants are affected it's manageable. Both times I had mites I could eradicate them, since the problem was caught early.

Wade Coleman · #6 09-23-2018, 08:37 PM

One of my phaleonopsis got spider mites and it began to go downhill fast. They got into the folds of the leaves and their scraping on the leaves resulted in infections that began to eat away at the plants tissue. I was about ready to give up on it until a friend of mine gave me some advice on how to save the plant. I took off the dying leaves because they were of no use to the plant anymore and probably harbored a lot of mites anyways. Then I got rubbing alcohol and rubbed the underside of the leaves about twice a week for several weeks and now I do a cleaning every couple weeks with rubbing alcohol because, like others said, you can’t really eliminate them, but you can control them. Since then, my phal has gone from slowly rotting away to growing a new leaf and tons of new roots.

Ray · #7 09-24-2018, 08:14 AM

I used to be a proponent of oils, particularly neem oil, but now try to avoid them altogether. The sticky residue can trap dust and other airborne crud, and I suppose there could be a problem with clogged stomata (although I doubt it), plus there is the potential burning factor.

Like others, I find soapy water to be just as effective, or if I'm in a killing, versus removal mood, Azamax.

malteseproverb · #8 09-24-2018, 06:00 PM

Has anyone tried predatory mites? Ones you can buy online and unleash in your house to eat spider mites and their eggs? I have had such a bad problem this year and have sooo many huge plants to treat that I'm considering it.

Kevstar · #9 09-25-2018, 07:42 AM

Quote:

Originally Posted by malteseproverb

Has anyone tried predatory mites? Ones you can buy online and unleash in your house to eat spider mites and their eggs? I have had such a bad problem this year and have sooo many huge plants to treat that I'm considering it.

I was actually reading about these last night.. who knew such a thing exists? The thought of unleashing loads of bugs in my house does creep me out a little bit!

malteseproverb · #10 09-25-2018, 10:24 AM

There are already so many mites and fungus gnats and spiders and other things floating around my house that how could I care if I added a few more in the mix, especially if they earn their keep? I just wonder if they actually work. I have a lot of plants that would be difficult to move outdoors to treat so this would be the best option for me.