@La_chica_gomela, sorry to claim ownership of our tomato plants. It’s just that I’m the only one who waters them, or even notices that they exist. =P Plus, they’re in my backyard, and you know…possession, fractional law, and all that.
@laureth, I think you may be on to something with the root initials. Searching for images of that in Google, I found an image that looks like what is on my plants. It’s out of focus, but clearly the same feature.
Also, I found this exposition :
“Tomato stem primordia may develop all along any tomato stem regardless of its proximity to the ground. Often it is a response to high humidity levels in the air or to excessive watering/rain around the roots. The plant attempts to compensate for the excess moisture around its soil roots by developing more roots. But the root initials themselves are not harmful to the plant. They are normal.
If you have a section of the garden that is showing a greater number of primordia and is also having wilt problems then it is likely that it is too wet there for some reason – poor drainage, too much watering or rain, etc. Diseases are more likely to develop there too.
Remember that roots need air as much as they need water and excessively wet soil deprives them of that needed air. More plants are killed by overwatering than by underwatering so when in doubt – don’t water and pray for less rain. ;) ”
Houston is very humid during the summer and I was watering the pots heavily to help the tomatoes through the summer. This is about the time the bumps developed.