HI,
I have been growing elephant garlic for about 7 years here in my CT garden and find that it is best to debud the flower heads on the garlic before it flowers. This sends strength back into the bulb and you get bigger bulbs.. Smitty

They also have rather an attractive flower. I usually plant a few just for the flower. I only see one in your pic. If the bulb is the important thing, cut off the scape.
Garlic has a rather large root ball, 30" or there abouts so if you can, put them in the ground, they should do much better. The one you show looks nice and healthy, but somewhat small in diameter.