That is not like any bacterial leaf spot that i've seen. What treatments you could use would depend on what is causing the problem, A) Bacterial, B) Fungal, C) Viral, D) Pests. Unfortunately, or fortunately, i do not know the proper treatment for spider mites. But there is a broad spectrum treatment that covers bacterial and fungal infections, copper-sulfate mix. Copper works well against bacteria whereas the sulphur component works well for fungal. Look for the words "copper-sulfate" on the bottle to make sure you are getting the right product, and concentrated formulas are your best bang for the buck. I would spray the plants outside, and let it dry for a tiny bit before bring them back inside. Use gloves and be sure to wash off anything that may drip onto your skin, remove your clothing and throw it into the wash because the ingredients are skin irritants. While i would look to get it treated asap, i would wait for more and hopefully better opinions before running out to the gardening store. There is a chance that it may be Viral (?). I would also try to isolate the infected plants. Good luck either way. Steve This post was edited by sjetski on Mon, Jan 6, 14 at 12:33

emyers, I doubt that Neem oil will be effective against your tomato leaf problem. It remains to be seen what the Copper Sulfate will do. Are you certain that the leaf spots you are seeing are bacterial, and not fungal as in Septoria Leaf Spot? The product GreenCure® is safe to use and effective against a number of foliage problems, including Septoria Leaf Spot. However, I think it would be ineffective against Bacterial Spot. I spray GreenCure on my zinnias to help maintain their foliage health, even though I am not an organic gardener. ZM

Serenade is organic www.agraquest.com

Well drop in gardner your more than welcome and see my plants.!!! Im near Glasgow. The horse chestnut stuff is a anti bacterial thingy that kills anything in the soil, foliage and plant. You would know this if you smelled the stuff as its like smelling uranium..lol...It will kill you the smell is so power full yer eyes water if smelled. So the bacteria hasnt a chance. Its especially great for young seedlings as it stops dampning off in them when they are vulnerable to fungus in the early days of growth. Its cheap to buy and easily available at any garden store. Arthur.