Sue, The dark spots on the lower surface sound like lace bugs. Whitish specks on the upper surface of leaves and dark spots varnish-like on the bottom are symptoms of Rhododendron Lace Bugs, Stephanitis rhododendri, and Azalea Lace Bugs, Stephanitis pyrioides, small insects with transparent wings on under-surface of leaves.. This insect hatches early in spring as the new foliage begins to mature and its numbers may build to damaging levels with successive generations. Lace bugs reach their peak in late summer and do their worst in sunny, exposed sites. Spiders are important predators of lace bugs and since they shy away from sunny, hot places, plant your azaleas where there is some shade. Insecticidal soap, horticultural oil, or a systemic insecticide may spare your azaleas the damage if applied in spring when the first hatchlings are noticed. Care must be taken to spray the lower surfaces of the leaves where the lace bugs live. Moving a plant to an area with more shade may alleviate the problem. Lace bugs are more prevalent on certain varieties. Cottony masses on underside of leaves are a symptom of egg masses of the Cottony Azalea Scale, Pulvinaria floccifera. They are up to 1/2 inch long. Control is the same as with other scale insects. The scale insects are what secrete the sugary substance that becomes sooty mold growth on stems and petioles. This includes Azalea Bark Scale, Eriococcus azalea, and Cottony Azalea Scale, Pulvinaria floccifera. These small sucking insects feed on the bark and exude a sticky substance that turns the stems black. A scale infestation is indicated by sooty mold on leaves, yellowing of leaves, and twig dieback. This scale is most obvious from May through June when white egg sacs may be found in twig forks. Heavy infestations over several seasons may kill plants. Overwintering immature scales (nymphs) are about 2 mm long, gray, and are usually found in twig forks. This scale primarily attacks azalea and rhododendron, but has also been found on andromeda, maple, arborvitae, willow, poplar, and hackberry. Azaleas can tolerate low populations of this scale without injury, and if there are no yellowing leaves, no treatment is necessary. Beneficial predators and parasites will usually provide adequate control of light scale infestations. Examine egg sacs for holes which indicates control by parasites, and look for predators such as ladybird beetles. To control heavy infestations, spray dormant plants with a late oil spray to kill developing nymphs on twigs. If necessary a 2% summer rate of horticultural oil may be applied in July after all of the eggs have hatched.

Lowes is the only place I know where you can buy it. If you don't have a Lowes near you, try finding Lowes online and ordering that way. It should only take a few days to get to you. If its any consolation, I have to drive to the next town over (about 35 miles away) to find a Lowes, so I can buy the right Bayer product. Kate

There is a thi8ng called Intergrated Pest Management. It basically says to inspect your garden daily for pests and see if there is another way of dealing with them, like picking off blackspotted leaves as they start. It also says is the problem big enough to need to use chemicals. I walk thru my rose garden everyday. This way I know what's going on. If I see bs starting on a plant I can pick off those leaves. if it is one plant that's worse than the others, yes, remove it. I dug up Peace for that reason. If you know you will have bs, start off the season with a good spray program and you won't have it at all. Unless it's raining all the time and you can't do it like what happened to me a few years ago! These are just some suggestions to help you.

Yes, lime-supher mix in winter sprayed or poured with a watering can with a 'rose' head over the whole bush after you have done your winter prune and over the surrounding soil so as to kill off the (fungal) spores that winter over in the soil. And, I reckon at least monthly, spray with a fungicide such as Triphorine perhaps a bit more often if you are also suffering mildew. Good air circulation for roses is also important especially in humid areas. You might also consider varieties resistant to diseases, such as the old fashion varieties - they may not repeat flower as much as the modern hybrids but they are, generally, much more resistant.