Extending tomato height

Anyway, getting back to the topic, You can double the height of a good tomato plant by letting the first armpit sprout under the first truss grow. Obviously though it needs a bit more room. I've got a gardeners delight growing that has just reached the top with both vines and has about 15 trusses on it. The largest has got about 125 tomatoes developing and about 100 more flowers that possibly could.

So far, I've only had 800g off it but I'm hoping for over 7kg. It started a bit late as it is one i grafted (don't think that would affect its vigour except to enable it to grow in diseased soil) and that sets them back a couple of weeks. Next year, I'll have to start them off a couple of weeks earlier which would mean sowing about 1st March. I think I'll be saving some seeds off it this year.