Can you describe the fungus that you've identified? We can't help you with a 'cure' until we know what the problem is. It will also help if you let us know which kinds of plants seem to be affected.

The link below will take you to all the recent discussions on organic fungus controls. Scroll down to the messages with the blue borders. Several recipes are included in some of the posts.

However, as rhizo pointed out you first need to ID which fungus infection you are dealing with and which plants are affected. Different controls work on different plants and only against different fungi.

Given all the rain I have heard about in IN lately you need to be aware that control is going to be very difficult. Judicial pruning and opening up areas to increased sun and air exposure can help but the most effective broad-spectrum control is one of the Daconil products - likely what you have tried. And even its effect once the fungus is established is apparently limited.

Serenade is another product I have heard good reports on so you might want to research it a bit too.

Good luck!

Dave

Here is a link that might be useful: Organic Fungus Controls

A good general fungicide was developed at Cornell University:

Tbs. baking soda,
1 Tbs. vegetable oil
1 Tbs. insecticidal soap
1 gallon of water

It is effective but it must be applied before there are any signs of fungal disease. It is, like virtually all other fungicides, a preventive -- not a cure.

Since your plants are already infected, consider it a learning experience and plan for next year by incorporating plenty of compost from at least five different materials into your soil. The nutrients from the compost give your vegetable plants what they need to fight off disease as best they can in the first place. Also look for disease resistant varieties to plant.

Fungicides, whether purchased or homemade, doesn't get rid of damage you see. Instead, they are meant to protect new foliage against infection.

Beyond that -- please brace yourself for a mini-lecture -- never spray if there's a wind and/or breeze.

Serenade

As far as a fungus, the tomatos have a spot on them, I know it's a fungus I just can't remember the name right now

{{gwi:85207}}

THe cucumbers I think have powdery mildew, but they seem to be the least infected. To be honest about the squash and zucchini, I am not 100% sure what they have, I only know that they are turning yellow and dying.

Neem oil is an organic fungicide.

I've lately been hit with powdery mildew on my pumpkins thanks to the last week of rain and insane humidity.

Anyways the way I'm dealing with it is diluting skim milk with water (1 part skim to 9 parts water) then spraying all the leaves with that. The leaves that are goners I just clip off and throw away.

For your tomatoes I would recommend doing the same. Spray them with the diluted skim milk, and clip off the infected leaves. Remove them and any dead leaves on the ground and put them in the garbage can to stop the spread of the disease. It also looks like you have some tomato branches/leaves touching the ground. I myself do not prune the suckers on my tomatoes but I do remove any foilage that is touching the ground. Also make sure to mulch around the stem of your tomatoes with straw or w/e you have laying around to prevent water from splashing from the ground onto your leaves. That's how most diseases infect tomato plants.

Old zucchini leaves will yellow up and die, that's normal.

That would be milk, dear. Plain old ordinary milk. Dilute it a bit and spray after the rain. Better yet, use the leftover milk the kids leave at the table.

Easy AND Cheap!

I had powdery mildew on one of my peonies and after trying all the organic methods (opening up the plant with pruning, baking soda, etc.) the best thing I found that rid the plant of the disease was to mix in a ordinary spray bottle one or two tablespoons chlorine bleach (Clorox) then fill the bottle with water. Early in the morning I sprayed the plant throughly with this mixture until all the leaves were dripping, left it on for about 10 minutes then hosed the plant down. Got rid of the mildew and it hasn't come back or had a chance to spread to the rest of the garden. This is the first year in many where my lilacs are mildew free and I really atribute it to that initial spraying which prevented the fungus from spreading throughout the garden. I don't know if it would work on the black spot fungus on your tomatoes, but it probably wouldn't make them any worse than they already are right now.

I have found that GreenCure® is a pretty good organic fungicide.

MM

Unless I am missing something, GreenCure is baking soda and water. I certainly have found baking soda (1 rounded tablespoon) and water (1 gallon) to be an effective fungicide, but there would have to be something more to the product for me to not just make my own.

I guess I was missing something, it's potassium bicarbonate in GreenCure, not sodium bicarbonate. Guess I should read more carefully.