The tomato trellis is one of many ways to support tomato plants (some others are tomato cages, tomato ladders, and simply staking tomatoes).
Trellises seem to work best in a garden design when used along walls and up the center of garden plots, and of course you'll want to pick a color that goes with your garden design.
Here are some tomato trellises I found recently that looked interesting (click on the photos to learn more about them):
Here's a "zig-zag" trellis that would be nice going down the center of a rectangular or oval garden plot. It comes in two sizes, 38" tall and 66" tall and has holes large enough for even a giant tomato to get through.
It only comes in silver, but I suppose if you really wanted this in another color you could spray-paint it the color you wanted.
Here's another trellis -- this one can be used flat against a wall (you might want to secure it in some way if you use it like that), as a "zig-zag" trellis, or close the ends to make it into a triangular tomato cage.
It comes in "cherry red" which would be very attractive in a red garden, a children's garden, or as an accent in any edible garden.
From the reviews, this seems to be a very versatile trellis: you can use it in raised beds, containers, or as a stand-alone trellis by a wall. It's sturdy enough to hold a large tomato plant and has multiple "feet", so you shouldn't have to secure it unless you were expecting high winds.
I'm very partial to the color as I'm using black for my edible front yard garden's accents ... so I would probably choose this one if I were buying a trellis from the list here. It comes in 36" and 72" heights.
You certainly don't have to!
I've used a chain link fence as a trellis for my tomatoes with some success, using ties to hold the tomato plants in place. I think this works best with cherry tomato plants, as they are easier to weave between the mesh -- then you don't have to tie the plants up.
An alternative would be to use stakes and 4-6" (10-15cm) wire mesh as a trellis.
Another alternative is to plant your tomatoes around your compost bin. Since tomatoes like warmth, moisture and can be heavy feeders, I've found this location to be ideal. Just secure your tomatoes to the sides of the bin as they grow.
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