The stock tomato cages do need to be modified slightly before you begin. You will need to make two cuts per cage. On the left you will see the cage after being cut. Notice that when placed upside down, the top ring is cut completely off. This allows you to draw the 3 legs together. One other cut is needed on the center ring. In the enlarged picture below you can see this cut on the right. This is so you can overlap about 1 inch of the ring as you draw the legs together so the tree stays uniform in shape. To cut the cages I used an angle grinder with a metal cutting blade on it, but it would be just as easy with bolt cutters if you have them.
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