How do you know if it's spider mites? I have noticed some fine webbing around the growth tips of some of my Japanese maples and just assumed it was spiders. Now you've got me worried. I sprayed my trees with insecticidal soap this morning, as the label said it was effective on mites. We'll see.

Insecticidal soaps are effective against spider mites. Read and follow directions carefully.

To do a spider mite scout, tap the affected plant parts against a white sheet of paper and see if any of the debris that lands on the paper moves after a few seconds. Spider mites can be seen with the naked eye on the underside of leaves, in particular.

Update: I found an organic recipe for spider mites online using buttermilk and wheat flower mixed with water and I've sprayed my flower beds and herbs paying particular attention to the roses (undersides and tops) for the last two nights in a row. I'm doing nothing tonight and we're having a gentle rain anyway. On inspection, I'm seeing far less of the mites, damage and webs going on. But..being a doubting Thomas, I'm not convinced it's the spray just yet. Time will tell and I'll share more when it looks more definitive. Anything to avoid using chemicals and killing every other good bug out there in the process.
-Nan