My sister-in-law has a problem with several of her plants. Some of the leaves are absolutely covered in brownish spots so close that all you see are the spots.

The affected plants include red valerian, daisy, bleeding heart. They are in different locations on different ends of the property. Other plants nearby appear unaffected.

Any thoughts? Some of the valerian had blackish dots as well. The spots are fairly regular in shape. I think they had a slightly darker margin. Sorry, I don't have a picture. Thanks.