Hi!
In regards to your question, i believe the problem is root-nodes, You may
need to cover the roots up with soil, otherwise this is what causes root
damage.
I'm not sure about your second question, as here in Canada our tomato plants
die off with the first frost.
Good-luck!! peppergirl
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"JorgNS" wrote in message
...
This is the first season that I've tried growing tomatoes and due to lack
of
space, I'm growing them in pots. I have several varieties of heirlooms
growing. I've noticed that on a couple of plants, the base of the stems
have
bumps growing. Is this a disease or is this normal? Also, at the end of
the
season should I discard the plants or will they come back next season? I
live
in Southern Calif. in the valley where the summer has been hitting the
90's and
the winters get into the 40's. Thanks.