You really need to provide a photograph.

Try finding your disease on this link

Here is a link that might be useful: Disease ID link

I'm one who doesn't have a camera so if you could describe what you saw with those diseased plants that would help a lot. It would also help if you could share with us what gardening zone you're in or a rough idea of where you grow, in a geographic sense. And that b'c tomato diseases are regionalized so not every one is found in all places.

The most common are the foliage diseases. I didn't look at the link provided, but the four most common foliage diseases are Early Blight ( A. solani), Septoria LEaf Spot, both fungal and Bacterial Speck and Bacterial Spot.

Those diseases are Ided primarily by the distinctive lesions on the upper leaf surface.

I'm curious, but why did your friened say the disease was in the soil? That's perfectly possible depending on where you garden and diseases such as Fusarium and even Root Knot Nematodes and many more are possible.

But it will depend on the pictures you show, if you can, and if not, the way you describe the symptoms.

Carolyn, whose good camera was stolen years ago and she's never been interested in getting a new one. ( smile)

Early blight, late blight, and Septoria leaf spot are common tomato diseases caused by fungi. The fungi overwinter in the soil. That's why a good preventative measure is to rotate your tomato crop each year. You can also grow disease-resistant varieties. You can read more through the link below. Good luck!

Here is a link that might be useful: Different kinds of tomato blight and how to tell them apart

Late blight does not overwinter in the soil. It survives on living tissue.

Early blight, late blight, and Septoria leaf spot are common tomato diseases caused by fungi. The fungi overwinter in the soil. That's why a good preventative measure is to rotate your tomato crop each year. You can also grow disease-resistant varieties. You can read more through the link below. Good luck!

*****

As has been noted, late Blight ( P. infestans) does not overwinter except in certain areas of the US where the two mating types are present and then the sexual oospores can do so.

But having posted online since the early 80's I can share with you that there are a lot more tomato diseases/conditions that folks refer to as "blight" than the few foliage ones in that link, which I thought was quite incomplete.

There is no need to rotate your tomatoes every year, many folks simply don't have the room to do that.

For the foliage diseases prevention is the key, spraying with a good anti-fungal ASAP after the plsnts are outside. The two fungal diseases of Early Blight ( A. solani) and Septoria Leaf Spot are perhaps the two most common ones worldwide. The two bacterial ones which I don't even think were mentioned in that link, are Bacterial Speck and Spot and prevention for them is not all that effective.

Again, speaking only to the foliage diseases, all NEW ones are acquired via air and embedded in rain droplets. But any diseased plants also can shed spores and bacteria to the ground and then the next year rain and irrigation can splash back those pathogens to the lower leaves of the plant and away it goes up the plant. Mulching can help prevent splashback.

One of the best thigs to do is in the Fall to turn over the soil deeply, not just with a tiller, to bury any spores and bacteria that may have fallen to the ground so that they're buried very deeply.

But again, blight to most folks means a sick looking plant and there are lots of possibilities for that including the systemic tomato diseases, nutritional problems and the weather in any one season.

I grew my tomatoes on the same 1/2 acre field for about 16 years and never had a buildup of pathogens in the soil.

Hope that helps.

Carolyn