Ready to wage war on spider mites - Orchid Board

jocierk · #1 09-09-2015, 03:14 PM

OK I need some opinions. I have a spider mite problem that is getting worse. It started out with a few (small but visible to the naked eye) mites and some webbing. I set up the humidifier, started misting every morning (they all get rinsed once a week when I water), and did two rounds of spraying neem/bayer. After the bayer they were gone. Then a few weeks later I noticed that some of the leaves on my phal hybrids were not looking good and I realized the accompanying "rusty powder" was more freakin mites. I have continued all of the above but its not getting rid of the new ones (which are MUCH smaller and red instead of grayish), and they are spreading. I have a jewelers loupe on order so I will know for sure but I think they have to be a different kind (or maybe life stage) of spider mite...which brings me to my question: What methods of mite control/products have worked best for you guys?

Some background info on my setup: All the orchids are located in sunroom addition on the back of my house. One whole wall is windows which is where they sit, the other three walls (and the window sills for that matter) are not water tight so I can't just go spraying a hose everywhere. That said all the orchid shelves sit on tile and I do mist them heavy every morning. I keep the humidity about 60-75 and the temp is around 80 with a 5-10 degree drop at night. On really hot days it is warmer. The room has one ceiling fan and a smallish window on the opposite wall from the orchids. They get natural light from the windows but they also get supplemental light from hanging T5s. There is also a door that leads out to my back porch. The whole setup is kind of somewhere in between having a greenhouse and keeping them indoors. I can't really get the humidity any higher than it is without worrying about rotting out my windows and I can't cool the room off any more than adding a box fan would do. However as the outside temps drop the room temp will also because three of its walls are exterior facing and one of them is all windows.

Like I said the bayer worked good on the small grey mites but doesn't seem to work on the tiny red ones. I have considered lots of different pesticides as well as introducing predator mites but I want to know what has worked well for you guys.

Sorry this post is so long...just wanted to give as much background info as I could. Thanks so much for any advice you have to offer!

katrina · #2 09-09-2015, 04:52 PM

The only true and absolute KILL for mites is a miticide. The Bayer product will help to control them but it's not a true miticide. I know...because I use both.

The bayer product is fine when you have a few and or catch thing really early and stay on top of it but, quite frankly, a strong spray from the hose will do just as good as the bayer product at eliminating "spider mites". When the populations are high a good, general miticide is in order. They aren't cheap and one bottle will last forever. Even better...would be to find a friend or 5 to go in on it and all of you share the product. Seriously, one bottle can go a really looooooooong way.

A miticide will kill the eggs and the adult phase. You still want to do a couple of treatments at appropriately timed intervals but this will actually kill them vs just knock them back. If your infestation is really bad then you might need a third treatment..but that's not usually necessary. I've never found it necessary not even in my worst infestation. And trust me, the Ctsm are magnets for the little b*****ds

I have used Floramite and I think it was Avid...both with good results. There are others on the market so you can look around and see what might be your best buy just be sure you are buying something that clearly says it's a miticide and that it kills *spider* mites. "Controls mites" really means next to nothing because there are many types of mites and not all of them are spider mites. Something that can kill "mites" might not kill "spider mites" so look for a spider mites as a target pest.

Ray · #3 09-09-2015, 05:03 PM

Heat and dry are mites' friends, so if you can reverse those, it will help.

SucraShield is also an excellent miticide and insecticide that desiccates all stages of soft-bodied bugs, yet it is relatively inexpensive, and is safe to use in the home, on food crops, etc, without being a risk to honey bees, which others can.

One thing more: treat ALL your plants, wetting them thoroughly, and repeat weekly for a month. Eggs can remain dormant for that long!

Greystar · #4 09-16-2015, 05:57 AM

When I have mites I like to get a damp tissue and wipe down each leaf to try and get all signs of visible webbing.
At first I use a potassium salt based pesticide. I wait a few days and then apply an oil based one. Repeat a week later
Make sure that you get into nooks and crannies such as the place where the leaves start growing from and also give a light application to the top of the media afterwards which may help get the ones that may have fallen off.

milks · #5 09-16-2015, 07:04 AM

I don't know if you can get this stuff where you are but I really like SB Plant Invigorator (S B Plant Invigorator). It is effective and non toxic so better for your plants and the general environment.

Also because it works by suffocation the mites cannot become resistant to it as can happen with a pesticide. I've used it to control spider mites in the past. The only downside is it needs to be applied for a few weeks as it has no effect on the eggs so the mites will come back if stopped too soon

Leafmite · #6 09-16-2015, 12:04 PM

I hope my mites are all gone. I had a problem with them this past winter and I cleaned the orchids and other plants off under the faucet and then applied Lacewing larva. The new leaves/growths all look great but we shall see once the plants are indoors once more....

Brooke · #7 09-16-2015, 04:59 PM

Did anyone in your family object to having bugs flying around your house? How long did they last once they hatched out?

Brooke

NikolaAnne · #8 09-16-2015, 06:12 PM

Apparently, HairSpray also works, because of the suffocation thing...

Leafmite · #9 09-16-2015, 10:01 PM

Quote:

Originally Posted by Brooke

Did anyone in your family object to having bugs flying around your house? How long did they last once they hatched out?

Brooke

I had to laugh because, yes, my family would have been horrified to have them flying around indoors. I had to wait to receive the eggs until my plants were nearly ready to go outside. Growing plants in the home is just not the same as growing in a greenhouse. I usually do get away with a few ladybugs, though.
I am not sure how long it took for them to become adults. I did see some ladybug larva on the plants as well so I am not sure who exactly did all the work. I just hope the mites are gone.

bil · #10 09-17-2015, 06:34 AM

So far (touch wood) they haven't bothered my orchids, but we do get them badly on the tomatoes, the dahlias and some of the roses.
I use a chemical megadeath product, and it deals with the problem nicely. I have tried several natural products here on a variety of problems, but none of them really cut it.