Spider Mites on Renanthera, time to toss?
 

About a month ago my renathera started to look brown and blotchy and the newest leaf especially, a while later I noticed the top leaves were covered in a red dust, so I cleaned it off with alcohol just incase, the new leaf bit the dust and the leaf under that is nearly gone as well. Then a week later it was covered in the red specks, this time I had done more research and out of everything they looked like spider mites, the bottoms of the leaves never looked different, no webbing and the red dots always on the top leaves so it does seem a little bit different than what you hear. This time out of the dozens probably 100 specks on the top leaves I managed to see one move very slowly, I should've taken a pic, they literally looked like rest dust, like if I had sanded a brick over the plant, very tiny. Anyhow, the plant looks awful now and I'm just wondering what to do about it, I'd rather toss it than risk infecting others if it hasn't already. After the last red specks I took all my plants nearby and gave them an alcohol treatment, and with the renanthera I removed the lava rock and boiled it and bleached all the pots and I bleached the plant and hosed it down. It's been near 2 weeks since then, no red dust, but I did notice a few dew drops on the bottom and am wondering if they're there and sucking the plant? Any ideas or should I just toss it? It's ugly now.

Treat with a 3-in-1 (rose?) systemic. I have roses and I use the granular stuff on some of my house plants and all the sucking insects disappear. They have the spray most places. It is highly effective.

Tossing it sounds like an extreme. I haven't had any problem with controlling spider mites. High humidity, lower temp, and spray insecticidal soap every 5 days or so for a while. Even a wimpy product like Safer Insecticidal soap was enough. I've never used systemic which Leafmite, but it may be easier. If you are using non-systemic stuff, you'll need to repeat the spray many times. Waiting for 2 weeks before the follow-up treatment (alcohol, insecticide etc) could be a problem. Some species could complete a generation in 5 days. So even if you don't see them, you need to keep repeating the treatment for a while. Maybe the following info will help:

https://www.sdstate.edu/ps/Severin-M...ed-Orchids.pdf

I wouldn't give up yet, but be sure to keep it isolated so they don't spread to other plants.

Also, once the damage is done it is done and will remain unsightly. I had a break out of mites last year and have had to live with the damage done although unsightly. It still looks like they are infected, but testing with a white paper towel tells me they are gone. I sprayed and sprayed and sprayed for weeks to get rid of them all though.

If you are talking about a product from Bayer the only granules that I know of do not contain any ingredients believed to be effective against mites. Bayer does have some sprays that contain a synthetic pyrethroid that may be effective against mites. You have to be careful with Bayer products to very carefully specify the exact name of the product as Bayer has a number of different products with similar names and front labels.