It looks like possible transplant shock. Make sure it is watered, and put it in a shaded spot for a couple of days until it perks back up.

He'll be fine. Water, filtered light for a day or two, and all will be well. :)

I don't see anything wrong with the plant in the photo other than putting that tiny cage on it was a waste of time and effort as it is already outgrowing it. But as others have said a day or two of partial shade after transplanting is usually all that is needed for the plant to recover.

If it is a Big Boy it is going to need something far more substantial and 4x taller than that for support, but I have to say that plant was very likely mis-labeled. Based on the photo, Its growth pattern and node lengths certainly don't look like a Big Boy. It has the appearance and growth patterns of a determinate variety, not an indeterminate.

Dave

Is this the same BIG BEEF plant ?