Q. How do I keep tomato vines from growing too tall? I have four, six foot bamboo poles, four feet apart with two pieces of wire running through them. I don’t want the tomato plants going any higher. Any suggestions? Is my set up ok?
A. The short and easy answer is – cut the growing tip off at the height you want the plant to stop growing.
Perhaps more important questions might include –
1) why do you want to stop them at 6′? You could let them turn and come back down, thereby getting another 6′ of growth and production – depending on the length of your growing season. If you have frost, it’s most productive to cut the tip off 8 weeks before the average first frost date, since they won’t have time to mature fruit – unless you are going to protect them.
2) Are the poles and wires strong enough to carry the weight of 6 tomato plants each, with each plant carrying as much as 20# of fruit?
3) What are you using to encourage the tomato plants to grow vertically? Hopefully it’s not wire, which usually is too thin and hard, and will cut through and/or break your vines. Use baling twine or something nylon that is similarly heavy and strong.
4) Are you planting your tomatoes in one row, with alternating plants going to opposite sides of a T-type frame, so they all receive enough light? Planting in one row isn’t mandatory, but it gives you access to the soil-bed or Grow-Box for weeding, feeding, and watering. Just plant in double rows for a year, and you’ll see the wisdom of one row.
5) If you are able to find (preferably used – for saving $) 1/2″ galvanized plumbing pipe, that is stiffer and better to work with than wire across the top of your poles/frames, etc.
I recommend you look at the photos of the Hogle Zoo garden’s tomato plants growing vertically on T-Frames, for ideas on how to improve your set-up. You can find them at https://groups.yahoo.com/group/MittleiderMethodGardening/