I transplanted my (home-grown from seed) tomato plants (three varieties) about a week ago.
From what I was able to determine, my zone is 8a here in Vancouver, Washington state.
The weather has been erratic lately - ranging from dry and in the low 80's, to wet and in the high 50's. At night, it'll plunge down to about 50-55 degree range.

I'm a pretty seasoned tomato grower, but this one's got me stumped. There are brown streaks up the stems; the leaves aren't affected, and the plants seem to be growing well, but since I've found the same characteristics on three different heirloom varieties (Pineapple tomato, Gypsy (black), and cherry), I figured it has to be a disease or deficiency of some kind.
I had a similar problem late in the growing season last year, but so late that it was rather cool, and didn't affect production (I remove the late green ones in early November).
If it's a potential problem, and there's something I can do to save my plants now, then I'll definitely pull out all the stops to do so - I just need to know what it is first!
If you know what it is, I'd very much appreciate a diagnosis!

Thanks!

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