Thanks to some nice people on The Tomatoville Forum I can now show you how they make their tomato cages from concrete meshing. I will quote the text from their post. I am sure you could find concrete mesh quite easily.
Please note from 3rd September Tomatoville will be a members only forum. But well worth joining if you are a tomato fan.
Home Depot sells 5x150' rolls of 6" concrete mesh for $120. Using 13 squares (6.5') per cage, one roll of mesh will make 23 cages. The full roll is heavy – 150lbs – so use a dolly or a friend to help you move it.
A-clamps or a helper will keep the roll from springing open when the ends are straightened out.
Wood, bricks or container plants can be used to manage the roll and keep it from getting away from you. (It wants to unwind more than you may want it to...)
Count out the number of 6" squares for the size cage you want – I used 13 squares – and cut each horizontal wire tightly against the 5' vertical wire. That'll make all the ends the same length and give you a clean vertical wire at the beginning of the next 6.5' length.
You can use the pliers to bend the ends – but I had a nut driver with a hole drilled about an inch or so up into the shaft. The fixed depth of the hollow gave me consistent length bends without having to measure.
Bent ends form hooks that grab the vertical wire at the other end once rolled.
Overlapping the ends by one 6" square keeps the cage round and gives you something to hold onto when hooking all the ends in place.
The cage should hold itself together without additional fasteners or welding. I used wire-ties to prevent any surprise movement or dismemberment that might occur once the cage is weighted down with tomatoes.
Thanks to Thawley for his pictures and great advice.
Here are some pictures of the cages in use. The first picture is thanks to Ruth10
Ruth's comments; The wire Thawley is using is galvanized, so no rust. This is distinct from the concrete reinforcing wire, which is not galvanized and comes "pre-rusted." I suspect the galvanized wire is slightly more expensive, but I've never done a pricing comparison of the two. And, yes, you want to watch out when you're working with those rolls. They can jump out and bite you.
I used the galvanized wire from a large roll as in Thawley's photos. A large T-bar pounded into the ground and wired on supports the cage.
Now a selection from Korney 19. With his comments
I bought galvanized sheets a few yrs ago and made a large variety of cage configurations. Triangular cages I use 1 plant in each corner. I also make 3ft x 7ft "pens" and various sizes of "stalls."
Here's a 3ft x 7ft pen that holds container tomatoes, anywhere from 8 thru 12 plants:
And here's a way to both anchor and EXTEND the height of your CRW cages:
You cut the bottom ring where it joins each vertical wire (only 1 cut per square) and then bend each down, from horizontal to a vertical position.
Finally how the larger growers use them. Pictures thanks to Granite26.
I use a 5" section of rewire cutting the bottom edge off which makes a bunch of prongs to stick into the ground. This holds them in the ground well for me.
Well that's it for now folks, I hope this post gives you some insight as to how they do it across the pond and I am sure I will be trying their method sometime next season. In future post, I will tell you more about the varieties they grow and other methods used. As I have said, the climate and conditions are different all over the globe for growing tomatoes, but basically they all like light and heat and hate frost, so we are not too far apart wherever we grow them.