Hi Normandy! I tried something similar... a thick metal pole that hung the tomato plants upside down. Really bad idea... the tomatoes didn’t grow well at all (they just didn’t root the way they should) and a breeze knocked the thing over. Unfortunately, I was weeding underneath the thing when it toppled over. Saw stars and gave me a good gash on top of my head. We now laugh at the incident but for a minute there... I thought it would be “death by tomato plants”. Save your money and use pots or plain old (non lethal) dirt.
Thanks for the tip! Something to avoid :)