A visit to the Scherrer Vineyard in the California's Alexander Valley a few year's back provided the inspiration for my current trellising system. Pictured at right is octogenarian grape grower Ed Scherrer's trellising system. Ed treats tomatoes like vines, saying "they want to grow up, so let them".
His trellis is a fairly simply tacked together wood and metal fence of sorts. There are a few keys to its success:
1) Each stake is firmly anchored into the ground (buried roughly 8-12 inches). As the vines become heavy with fruit and thick with leaves, they risk toppling the 'fence' under their weight, and can act as sails, catching lots of wind. Deeply planted stakes help to solve this problem.
2) The cross bars are firmly attached, but the work they do in supporting the plants is minimal. The plant is directed back in towards the fence with a long string tied to one end and woven through the fence as the plants grow. Having multiple levels of garden string that begin near the base is key. Waiting to tie the plants to the fence once they are too big creates pressure that can cut the stem. As they grow, this means a new string once every ten days to 2 weeks.
3) The fact that the plants grow up means that the fruit is exposed to wind, which helps prevent rot after a rain, and of course avoids contact with the soil.
Here are the fences we have built and used for the past three years. Next year, they will need to be replaced.
We move them into a new bed each year in the interest of crop rotation, and because it allows us to scope out the ideal spot. We are fortunate to have good room in our raised beds and we can experiment with a north / south vs. east / west alingment. This picture is north / south, and it appears to be doing quite well.
One other development this year is the addition of metal labels for each plant. We have a habit of either losing tags or having the marker wear off over time. Using a home labeler, my folks made metal labels this year that are attached to the wood in the fence above each plant.
This might be the best new addtion to the garden this year.