can you post a picture of the plant ?

Early Blight.

Dave

Well it was getting worse, so I cut off all of the leaves that looked like that, so now there are just some leaves left at the top.

Here is a close up of one of the tomatoes

This leaf is just staring to turn

Did you apply a fungicide? It may help stop/slow the spread.

I haven't. I have heard that equal parts baking soda and vegetable oil mixed with water works?

I would spray it with fungicide, just in case.
Your plants look very healthy. Lower leaves can get like that for other reasons , me thinks.

Im a real noob with my toms and a "hypochondriac" some of my plants have similar issues but I am tending to think they are cultural and not actually early blight. Iike yours my stems, fruits and tops look fine but I have some significant yellowing/browning on the bottom. I have been using neem oil and baking soda to try to control insect and disease as I have a tight urban garden with some real built in challenges for air flow and spacing- seems to be helping hold trouble at bay - couldn't hurt. My problem is all the afflictions look so similar its hard to know - now with a week of hot rain predicted I am basically at the mercy of the gods I guess.

A dissenting voice: Doubt it's blight. Suspect it's water stress, as in shortage.

1. Please tell us what's the white stuff at the base of each plant.

2. Also how do you water -- Drip, hand held hose, or?

3. And how do you determine how often to water

4. as well as how long to water?

Early blight affects the leaves differently as described :

>>>Brown spots and yellow of leaves are signs of early blight. The leaves shown in the first picture doe not have that pattern. The are drying from the edges, WITH NO BROWN SPOTS ON THE LEAVES.
Further more , the subsequent pictures show normal plants.

JMO

Here is a picture showing a typical EB

It looks like Early blight. Yes, potassium bicarb sprays reported to be effective for EB, mmm, as much as anything is effective LOL
baking soda is step below than potassium bicarb.
You can use fungicides, not to stop but at least control it to a degree.

Here is a link that might be useful: EB

seysonn's response has image of early blight.

OP's image is *not* early blight.

Here's info from NCSU (see link)

And here's a portion of NCSU info:

"Infections of early blight usually begin when water splashes infected soil onto lower leaves or the stem. (The disease can also come on the plants from the garden center.) Soon afterwards, black spots develop that may be surrounded by a yellow area. The spots grow in size and number, spreading upwards towards the top of the plant. As the spots grow, they form a bulls-eye pattern. Lower leaves eventually wilt and fall off."

Hmmm. Doesn't sound like OP's plants or symptoms.

Here is a link that might be useful: early blight.

More images (Univ Maryland), with nice close-up of bull's eye pattern. (click link, please)

Here is a link that might be useful: early blight - bull's eye lesions

So if it's not early blight, should I worry about it? The white stuff is Epsom salt. I haven't watered much recently because it has been raining so much. But when I do I hand water with a hose. Usually I dig about 2 inches down to see how moist it is.

This post was edited by hopefull742 on Wed, Jul 16, 14 at 16:29

I did get some Neem Oil last night, and have sprayed it.
Thank you for all the answers!

Miriam

This post was edited by hopefull742 on Wed, Jul 16, 14 at 16:28

I do get similar leaves on my plants ( the very lower ones). They get yellow and the start drying up. Hot weather speeds up the process. I don't think that is a disease. But I just remove them. It is also getting close to my third round of anti fungal spray, as preventive measure.