Steve - Nashville, TN
A: This also happened to me! Sounds like the plants needed a little more time in the shade. Leave them where they are. Pound some stakes in the ground and hang a sheet canopy over the plants for a little more time of shade. Pound in a thin stake next to the plants and gently bind them up for a little support. I usually use a plastic grocery bag to stake up plants. The artichokes will look a little sad for a while, but they will come back. Don't worry if the plants shed some of its leaves. This is how artichokes generate energy to the more important part of the plant; such as the center and the roots.
The pic on the left is an artichoke that I bound up to help it through its transplanting shock. See: http://www.sweetheartartichokes.com/care02.htm. B-1 can also help give a plant the boost it needs for recovery. This can be purchased at Lowes or Home Depot. Let me know how it goes!
WILTING ARTICHOKE UPDATE:
It seems as though they needed a little more water. It's almost 5pm here and still holding steady at 91 degrees so I gave them another good soaking. After about 10 minutes they began to perk back up. I'm going to run a slow drip soaker hose through the garden in about an hour so and then water the whole garden just after dusk so they'll get a little more water then too. I think I just underestimated exactly how much water they need. I'll keep you posted. Steve