Over on the Tomato Pest & Diseases forum you'll find a long post called Problem Solver 2. Just use the forum search for that form if it isn't still on the front page. It is filled with links to images of the different tomato diseases. Browse them and see if you can find a pic that matches your problems. Off hand it sounds like you have a fungus problem (the black spots) from your description but I can't be sure without seeing it or a great many more details. If that is the case then spraying with an anti-fungus spray such as Daconil (sold under several different names) will help control it. The purpleing leaves and veins are due to stress - normal for a stressed plants - and will disappear once you ID the other problem and treat it. Good luck. Dave Here is a link that might be useful: Tomato Pests & Diseases forum

My jade has these black spots too. It is a baby jade my friend gave me (first one for me!)about an inch tall with 4 leaves and 2 tiny leaves at the top. After I transplanted it I didn't want to water it for a long time because I read the roots need to heal first, right? So, I kept it inside because it's been raining every day here in Florida. Then after about a week and a half inside, I put it outside. It got one heavy rain, but I have it in well-draining cactus soil, so assumed that was okay. It gets FULL FULL sun all day outside. After about another week outside I noticed all of my succulents that I had recently transplanted and moved inside and outside with this plant looked sunburned. It is weird to think this could happen to a desert plant, but they did. My aloe had red tan lines where the upper leaves blocked the lower leaves. A baby aloe I just moved to its own pot turned brown and squishy. Luckily, I moved it back inside and watered and it came back to a healthy green. Anyway, this after this sunburning, my jade leaves got a litte bumpy. They're still hard but they aren't waxy looking like I've seen on big jades. Then they developed these brown spots. Could this be from the sun. The spots look like they are part of the leaf and not a fungus. Sorry about such a long question, any ideas?

I was curious as to the history of tomato leaf sprays on roses. To do this I went to the Google Books site and checked full books only as that would then report books out of copyright. In 1877 a tomato leaf spray was reported to work for aphids on roses. Title: The Year-book of facts in science and art By John Timbs Published by Simpkin, Marshall, and Co., 1877 This effect is consistent with Hoovb's statement (I have reproduced his total statement, as the warning part I feel is important not just with a blender, but also if one selected to spray the mixture.): "It might have some pesticide or repellant properties, since tomatos are in the nightshade family. Tomato leaves and stems are poisonous. They contain an alkaloid that interferes with cholinergic nerves and cause some serious gastrointestinal distress. So make sure you clean your blender out thoroughly lest you poison yourself." Here is a link that might be useful: 1877 book page 40

Impossible to tell from your description just what was affecting your plants. LOTS of reasons why tomatoes can develop spots and not all are fungal issues. And problems which affect tomatoes tend to be quite different from problems that affect the squash family. Without photos illustrating the problems, it's hard to make assumptions about what's going on but I'm not sure you have a lot to worry about. If you maintain a hot composting process, a great many disease issues will be eliminated. Be sure to rotate your crops for next season.