I have Cala Lilies planted in a container outside. They are covered with all of these tiny black spots that smear brown when you rub it. It looks as if the whole stem and underside of the leaf are covered with freshly ground black pepper. I mean covered literally like a peppered steak.

Its a really bad infestation and I don't know what it is. I wiped the plants down and these little black bugs came back. ( I assume they are bugs, they don't crawl around.)

WTH is this? Should I just dispose of the plants and start fresh again with some new calas? I don't want this pepper stuff taking over my other plants (it hasn't seemed to). I can't post a pic cos I don't have a digital camera. Also the growth of my plants have seemed to really slow down.