Spider Mites on Catesetum

[Cymbaline]

A few days ago I posted a question about my Catesetum Monnierara Millennium Magic 'Witchcraft' leaves turning splotchy yellow.
Monnierara Millennium Magic 'Witchcraft'

Turns out it has Spider Mites. I noticed some webbing and tiny red bugs and the back of the leaves are now white and splotchy. It wasn't like this when I first posted.

Anyways I hope I caught it in time. I took it into my bathroom and washed the leaves off with water and wiped the leaves with a cotton pad. The cotton pad took off some yellowish film.

I can post a picture if interested but since I washed the leaves off and wiped it down it looks better.


I found a post here on the boards about using 70% Isopropyl Alcohol every 2-3 days for any attack and to treat the other plants.
Spider mites on Catasetum

I don't want to go overboard with my orchids so I'm asking here first. I want to buy some Isopropyl Alcohol to spray my current plants and in case these spider mites come back on my Catesetum.
I'm guessing Do people use the stuff full strength and it doesn't hurt any plants?

Is it a good preventative measure or is it overboard?

I have the plant in a room that gets 50+ % humidity and I often run a ceiling fan. I'm going to re-arrange my plants so the Catesetum gets more air flow .

[rbarata]

First, it's not possible to get rid of mites. At least, you can control their population but not erradicate them. They are everywhere and being microscopic they can be transported by air flow/draft.
The best way to deal with them is to use a solution of water with alchool and a neutral dishwasher detergent.
Spray the entire plant, medium also (and especially the underside of the leaves, where they prefer to live) with a 5 days interval for 3 weeks.
Then, place the plant in a more humid place because they don't thrive that much in humid environments.

For the solution I use ethilic alchool because I can't find another (just a few drops for half a liter). As for the detergent, a tea spoon for a liter of water.

NOTE: There's a really high probability that your other plants have them too.

[Cymbaline]

Originally Posted by rbarata

First, it's not possible to get rid of mites. At least, you can control their population but not erradicate them. They are everywhere and being microscopic they can be transported by air flow/draft.
The best way to deal with them is to use a solution of water with alchool and a neutral dishwasher detergent.
Spray the entire plant, medium also (and especially the underside of the leaves, where they prefer to live) with a 5 days interval for 3 weeks.
Then, place the plant in a more humid place because they don't thrive that much in humid environments.

For the solution I use ethilic alchool because I can't find another (just a few drops for half a liter). As for the detergent, a tea spoon for a liter of water.

NOTE: There's a really high probability that your other plants have them too.

Okay I'll give it a shot. Is there any ratio to how much alcohol , dish soap and water?

[rbarata]

Dishsoap: I use, a tea or, in severe cases, a soup spoon for a liter of water.
For isopropyl alchool, I know it's not as strong as ethilic so I'd sugest some of the more isopropyl experienced friends around here to give you advice.
Anyway, in my case, I use not more than a coffee spoon (2,5 ml) for a liter of water.

[Cymbaline]

Originally Posted by rbarata

Dishsoap: I use, a tea or, in severe cases, a soup spoon for a liter of water.
For isopropyl alchool, I know it's not as strong as ethilic so I'd sugest some of the more isopropyl experienced friends around here to give you advice.
Anyway, in my case, I use not more than a coffee spoon (2,5 ml) for a liter of water.

Thank You

[Roberta]

I spray 70% isopropyl alcohol on plants and even flowers with no harm. (I just stick a sprayer in the original bottle) It is quite helpful for mealybugs on Phals... (with mealies, its biggest advantage is that it dissolves the waxy coating that protects the bugs) Soapy water clogs the pores of insects and mites (which are arachnids not insects so insecticide doesn't kill them) Again, it only kills the adults that it hits, so it is necessary to be persistent, to get the successive generations that hatch from eggs. A miticide is more effective. Fortunately, the Monnierara will lose leaves soon anyway, giving you a break. But as rbarata said, you will still need to be vigilant with your other plants.

[SouthPark]

Dish soap or even natra soap ...... spray the whole plant very well (to drench levels) --- every part of the stem and leaves .... and even put the soap solution into the 'pocket' where the newly developing leaves emerge ..... and --- if even some of the potting media falls out ..... remember to tip the plant on its side to drain that pocket (to get rid of the water trapped in that pocket - to avoid rot etc).

Do this for every plant.

If the spidermites have damaged the leaves already, then that's no problem. The main thing is to get those spidermites under control. If under control and the damage is not incredibly nasty, then plant will likely resume growing (new/more leaves - if still in active growth stage). If not under control, the spidermites can/will kill the plant.

Keeping in mind that it's all natural. The spidermites are just doing their thing. But to keep the plant healthy and alive ----- immediate treatment is essential.

As a preventative ----- it can be beneficial to devise our own schedule ----- ie. provide the treatment every once in a while. This is to prevent or minimise leaf/plant damage before the spider mites have a chance to do their thing.

[aliceinwl]

I think if you have a small collection and are vigilant, mites can be eliminated. I’ve heard that resistance is a major problem if you’re using chemicals but not if you’re using something that physically kills them.

I don’t have a ton of plants and had a Dendrobium that I bought infested a couple of years back. I got a commercial organic insecticidal soap advertised to be effective against mites. I think I ended up dousing the plant weekly for 6-7 weeks. It’s been two years and I haven’t seen a resurgence. I do recognize that spraying down hundreds of plants for 6-7 weeks isn’t practical but it’s easy enough with smaller numbers.

[SouthPark]

It is also possible to ask any local nursery that grows lots of catasetum type plants how they handle spider mites. For relatively small collections, it's no problem (and actually - probably necessary) to do a soap type treatment. We can be sure that the large nurseries have their ways to control the spider mites. Possibly misting system followed by fans and good air-flow. I might ask about this one day.

Eg. Fred from SVO.

[Subrosa]

If you're going to use soap and alcohol to deal with mites there's a much more effective method. First you spray the plant with a systemic agent such as acephate or imidacloprid. Then use the soap along with some water to wash your hands. Then toast your victory with the alcohol of your choice.