It would help us confirm what the problem is if your tell us, in detail, what's happening with the plants.

Images help us make decisions also. Take closeup and also overall views.

You are just having an outbreak of spider mites....every gardener gets them and some years are worse than others....

The best and cheapest way to deal with them is to purchase some Garden Sulphur (Liquid or Powder) mix it up as per the manufacturers directions and apply with a sprayer on top and bottom of the foliage. This will get rid of the mites, but be prepared to spray again in a week because you may get another hatch of mites later on..........

Ian

I have brought samples into the nursery, and after inspection under a microscope it has been confirmed that there are spider mites (and eggs) present.

Ok, so Garden Sulpher.... In your experience does this work better than neem oil (which didn't do much for me) or insecticidal soap (which I am now trying.) Or, the over the counter miticides (I just bought one by Bayer and plan to spray tomorrow.) I just used the jet spray hose attachment on the limelights--- but I hate being so rough with them---flowers and all.

So none of you do anything preventative in the Spring? Just wondering if I missed the mark somewhere

The female mites over winter in leaf debris and start laying her eggs on the new foliage depending on the temperature etc.....so it is not practical to use dormant oils etc as a preventative method....
The most effective method is to catch the first outbreaks of mites to keep ahead of the hatching(s). A female is capable of laying a multitude of eggs over her life span...... I use garden sulphur because it is the cheapest way to go for large areas. I also have it on hand to use as a fungicide. Whatever you use, it must be a miticide (insecticidal soap is ineffective and Neem oil is not an instant bug killer)
If you use sulphur, make sure not to spray on a hot sunny day....better to wait until evening or early morning to reduce any foliage burning....follow the directions...

Ian

What was the first insecticide you used? Rotating neem and Dish soap eliminated them in my case.

Check out this thread.

Here is a link that might be useful: does this sound like spider mites?

There are so many opinions out there when it comes to gardening. I'm such a "right answer" type of gal---it drives me crazy. I suppose I have to just try it all and see what works for me. Neem oil did not. The first thing I started with was dish soap---that also didn't work for me. It heped a little bit, but I really think the problem was too far gone at that point. Others swear by the insecticidal soap on other forums... but you're saying it does nothing to mites (much like using a pesticide for 6 legged creatures without a miticide won't work?)

Off to get some sulpher!

As far as what I used to treat.... I used Avid on the boxwoods last weekend (got a very small sample on ebay---have enough to treat one more time, but got freaked out by comments on another forum and am wary to use it again.) So I bought Bayer's 3 in one insect disease and mite control. I had treated the limelights with a bayer fungicide (because that is what I originally thought was wrong.) I should probably wait a few days (which kills me watching the plants look so bad while I do nothing but spray them down with a hose.... which in turn makes them droopy and does nothing to help the flowers) until I treat with the miticide.

Off to get some sulpher---will at least use that for now and see how it goes. Thanks so much for everyone's advice

How has your weather been? Hot and dry like many places? That kind of weather causes spider mites to suck out more sap from the plants which causes them to mate more which produces more spider mites. The simplest control is to mist affected plants several times each day to raise the humidity around the plant which slows down the wee buggers.

Do some tests with the sulfur on your plants BEFORE you spray widely. Many plants are very sensitive to sulfur.

Insecticidal soap is actually quite helpful in controlling spider mites. It's action is physical, rather than chemical. It dessicates the exoskeletons of those little mites just as it does other insects. It's a worthy product to have in your arsenal.

kimmsr,
thank you---it has been very hot here in Cleveland. Glad to know that misting the plants does help.... On another forum I was told that misting them wouldn't do anything---The spray had to be forceful enough to make them fall off. I was willing to do that to the boxwoods, but doing that with my new guineas on the front porch was another story.... The flowers would fly right off! Good to know that misting the plants DOES indeed do something. I will start doing that again.

Imidacloprid should never be used on spidermites. It turns them into breeding machines. You also fail to see the significance in rotating these things on spidermites. Don't continue the same thing over and over. They are one of the best at creating a tolerance to any chemical but 2 different things rotated back to back every week does the job. You continue to move forward instead of looking at the mistakes you made 2 steps back. That's what was so wrong in the US majorities vote.

About misting, IME misting only works on two spotted spidermites. The others love humidity.

Makes sense---thank you!