I've been growing the same varieties for years, and save my own seed...but this year we have had great weather for tomatoes..and they are just now starting to outgrow my trellis set up! I have 10' conduit pipe that I can attach to the stakes I have in the ground now, but that will only give me a few more feet than I have now, and at this rate they'll outgrow that height, too. I am thinking that I have 6 feet of metal stake sticking out of the ground, and if I add the conduit, I'd have to attach it with wire, so to stabilize it, I'd need a good 4 feet against my metal stakes for stability...

I think that years of adding compost, drip irrigation, and this year's weather have all contributed...but what happens to production when the plants outgrow your highest wires?

I'm in the northeast, and just don't get the height like some of the warmer zones I've seen. They don't usually get this tall till the very end of the season...and my tomatoes are just now starting to ripen..(normal for my zone).