OP: "...the Sevin I used set up a nice cozy care free environment for the mites." Here's a paragraph (from the link below) that would implicate Sevin (and some other insecticides): "Spider mites frequently become a problem after applying insecticides. Such outbreaks are commonly a result of the insecticide killing off the mites natural enemies but also occur when certain insecticides stimulate mite reproduction. For example, spider mites exposed to carbaryl (Sevin) in the laboratory have been shown to reproduce faster than untreated populations. Carbaryl, some organophosphates, and some pyrethroids apparently also favor spider mites by increasing the level of nitrogen in leaves. Insecticides applied during hot weather usually appear to have the greatest effect, causing dramatic spider mite outbreaks within a few days." Here is a link that might be useful: Spider Mites, UCDavis

You can also use a natural diy spray. This will not hurt the spiders and its not harmful to you etc. Also it keeps bugs from coming in like roaches and also keeps ants at bay. You mix up in a spray bottle with water. Now the main ingredients are simple but you have to prepare in one of two ways. You can chop large into large pieces and put into a small boiler and and bring to a boil on the stove and if tho is the one chosen, make sure ti allow it to cool down before putting into the spray bottle. If there isn't enough to fill your bottle simply add water to the bottle. Now the other way is to take the ingredients and put them into a processor with a little water and puree it down. Take the bottle and fill with water and pour water into bowl and add the mix to it mixing well and pour it into bottle. The ingredients are 2 tbsps red cayenne pepper, a handful of dry bay leaves, half of a onion, and 1tbsp of garlic, after you get these processed or boiled down and into your bottle add 2 tsps if dawn dishwashing liquid. Make sure to shake the bottle real well before each use. You will have reapply it after it rains. This mix is not good for repelling those few things. If you plant a garden of veggies, tomatoes,etc. You can actually spray this mix onto you plants and even if they have veggies in the plant it is safe. This will not alter the taste in your veggies at all. It will not harm the plants either. You are not spraying the roots just the top from the ground up. Remember to rinse your veggies very well. This is actually safer than using 7 dust etc. As I mentioned earlier you will have to reapply after the rain and after watering your garden. Certain critters dont like the aroma of thus mix so it keeps them away to. I hope this helps. Enjoy!!!!

For good, a 10 mile wide asteroid splashing down nearby at 40,000 miles per hr. Otherwise get a better miticide. Avid or Florimite will give weeks if not months of control. There are many other good miticides to chose from. One wk is totally unacceptable. Even oil will do better than that. Look on Ebay for smaller quantities if the big bottles for a couple hundred are too much.

Sara, schefflera are infamous for being spider mite magnets, though perhaps not as bad as as their close relatives, English Ivy. I am also a fan of using an alcohol mist. Do you have any horticultural oils besides the Neem? Any of them are effective in the on going battle against spider mites, as long as you concentrate on getting the mist to the underside of the leaves. You do NOT need to spray every day! Whatever you use, read and follow the directions on the container! You can damage the plant 'skin' by using any product too often or making it too strong. That includes the rubbing alcohol. By the way, your best hope is to gain the upper hand over the mites, rather than eradicate them. You must have X-Ray eyes if you can spot one or two sitting on the leaves, lol! Once you get to the point that you have to search for them, you can work with a preventative schedule, rather than a curative.