Surfgrl, Florida weave is the way to go if your going to grow hundreds and thousands of tomatos, I was raised using cages and that is my perferd method but now that I market approx 600 tomatos I use the weave and it works very well
T post should work well for you. I was lucky enough to have some old scrap pipe that I use 7' and drive in the ground a foot, I don't prune and I grow mostly Indeterminates, Just tie off to the end post and go down one side and loop once around each post. Better yet go to the garden tools section on this site and find the thread Florida weave method.
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