I have grown tomaotes in the same bed for 25 years now with no sign of any disease, mostly because the soil is a well balanced, healthy soil that I add compost to every year and periodic soil tests tell me about the pH and nutrient levels. As long as you maintain the soil your tomatoes grow in in a good, healthy condition you should not need to be concerned with plant disease.

That is what confuses me. I add lots of amendment's every year and all season long. Grass clipping (organic), leaves, manure, veggie scraps, etc. My soil is in wonderful shape, nice and dark. It's easy to turn and loaded with worms. But I can honestly say, I've never had 100% disease free tomatoes, and this year, it was rampant, except for my cherry tomatoes. The leaves turn yellow, with black spots. Then the plant starts to turn brown and dry up. The tomatoes also are small with thick skin and black spots.

What is your soils pH?
What is the level of organic matter in your soil?
What is the nutrient level in your soil and is it in balance?
What does your soil smell like?
When was the last time you had a good, reliable soil test done by a good soil testing lab? Have you looked closely at your soil with these simple soils test?
1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top.

2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up.

3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart.

4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell.

5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy.
Lots of earthworms do indicate a high level of soil life, but id the major nutrients are not in balance then more then likely the minor nutrients will not be either, but the only way to know that is with that periodic soil test for pH and nutrients.

Hi gardeningmom2five...I would suggest that you grow your tomatos in large tubs that you could move to the most sunny area of your yard. I would suggest that you use a mix of peat moss...vermiculite/perlite...and sand. In the fall I would discard the mix to the compost pile. In the spring wash your tubs inside and out with a soap/bleach solution and rinse well. Refill with a new soil mix as stated above. Use some of the new hybrid tomatos that have more/better resistance to disease...and stay away from the heritage types. Fertilize with a seaweed/fish fertilizer like Neptunes Harvest. You should have good results. Franklin

Suggest you follow oldmainer's advice above. Also, after planting your tomatoes in pots, mulch each pot with coir (the coconut fiber sold at box stores or by the yard at nurseries). I have found this to be most effective to prevent water from splashing up onto the plants from the soil, which is the cause of many tomato disease problems.

Are you buying your tomato plants? Often disease problems originate with the grower. Best that you raise your own seedlings, sterilizing the potting soil before seed planting by pouring boiling water over the soil and allowing it to cool, then seeding.

If there is any commercial grower selling diseased plant stock there is a good probability that the states licensing agency would yank their business license. If you have a commercial grower that is knowingly selling diseased plant stock report them to your states Ag agency.

Not all tomato diseases are soil borne or soil persistent. Many are airborne. 2007 was a disaster year for me with tomato disease and it affected every tomato in my yard heirloom, hybrid, in ground and container grown.

Many plants died before they produced any ripe fruit.

Planting in the same soil for 2008 saw little in the way of disease and I didn't lose a single plant until frost.

You need to know what the disease is and it isn't always easy to know for certain. If you don't know what the disease is or if it is in the soil then I would hedge your bets for 2009 and plant some in the same soil and do a few in containers.

gardeningmom2five, did you have an especially rainy season and/or do you live in the Northeast? I have been reading about a blight that moved into our area in the past couple years that really takes off when it is wet. I can't remember what it is called. I had one bunch of tomatoes all get it about two years ago, and then this year in a completely different place with different seeds they all got it, but it was late enough that I got plenty of fruits anyhow. I wasn't sure if this year my tomatoes caught a virus from some daturas that volunteered right close by, though. Did your plants just brown from the bottom up?

I've seen contradictory stuff about planting the nightshade family in the same place. Some sources I have seen say tomatoes really like to be in the same place all the time. Others say you should rotate them.

Yes, I live in NE Ohio. The garden is in full (really full) sun, so against all odds, I still get disease lol.

We don't have disease problems anymore. Of course our soil is highly alkaline so things work differently but here's what we have and what we do.

Our surface soil is sand fill. The soil underneath is pulverized limestone. Below that is limestone rubble and rock. We have been collecting other people's leaves and our banana peels to make compost for 15 years. My wife faithfully scatters it on top of the soil under all her plants every year. That sets the stage with a soil full of microbes. Then I scatter ordinary corn meal underneath all the plants that we care about (roses, lemon, tomatoes, etc.) whenever I think about it. I rarely spray the tops of the plants but when I do I use milk or just plain generic baby shampoo (highly diluted).

Cornmeal and milk are foods for the soil and plant microbes. I can understand how they work. Soap is soap. I'm not sure what the mechanism is but more and more organic practitioners in the San Antonio area are using it against fungal disease. They claim good results, but I'm keeping my eyes and ears open.

What about spraying with baking soda or sulfur that I use for roses?

Both sulfur and baking soda are non specific fungicides. That means they kill everything and destabilize the balance of nature at the microbial level. Of course if you already have the disease, then your balance is unbalanced. I prefer to use a food approach to improve the health and population of the good microbes rather than a poison approach to kill the bad ones.

The problem with killing everything is that too often the bad microbes return first. Why? Because their food source (the plant) is still there and is untended by the good microbes (because they died in the poison attack). The bad bugs have to be there long enough for the population of predatory microbes (the good guys) to come back. Whereas if you fed the good guys first, none of that would have happened.

Corn meal works to eliminate disease by developing the population of Trichoderma species fungi. Trichoderma are predatory on other fungi - most notably the disease causing fungi. Apparently the fungi that decompose corn meal are excellent food for the Trichoderma. When the fungal population of the corn meal decomposers grows, then the population of Trichoderma grows. Then when the corn meal decomposers are all gone, there remains a huge population of hungry Trichoderma looking for more fungi to feed on. This process happens in about 10 days with visible results showing as new grass growth in about 20 days.

The mechanism for how and why milk and seaweed has not been explained to me. Both are food because they both contain protein, carbohydrates, vitamins, and minerals. It has been observed that there are as many as 20 "layers" of microbes living on the outside of plants (yes, in full sunlight). When you spray milk or seaweed on the exposed plant surfaces, you are sending food to those critters living there. Assuming they can use that food, then their health and populations should improve. That's my hypothesis.

I agree with crankyoldman. My toms in pots and in ground got creamed this yr with some kind of blight. Not much doubt the abnormal aount of rain had a lot to do with it.

Serenade Max is an organic fungicide that's pretty effective if you use it regularly. You should be able to find it at most nurseries. The pre-mix is kind of expensive though, so look for the concentrate that you can mix with water.

HTH