Ten years ago I could have given you an answer. Not now. Back then almost every single garlic sold in grocery stores were from Gilroy, CA (they call the town "The Garlic Capitol of the World"). It was going to be one of two varieties, though in reality, there is little if any difference in them. One was named "Early California" and the other "Late California". Catchy, huh. One was harvested early and.............well you know.
Now almost all the garlic seen outside of the Pacific-coast states is from China. Who knows what the variety is but it still looks like those two CA varieties. The Chinese (might) treat their garlic so that it will store longer, and if done so, it won't sprout well. I just don't know.
If you are serious about growing your own garlic, buy the higher quality, larger bulb-size varieties. In Orlando you can grow hardneck, softneck, and Creole - all three categories of garlic. You would probably plant in late October to mid-November, by your county Extension Service folks can tell you when to plant. I'm in NE Mississippi and I plant all my garlic in mid-October. I have already harvested all my hardneck and will be bagging it over the next several days. The softneck and Creole will be dug up this coming week, after I have cleared all the hardneck out of my greenhouse. Garlic should be cured for a couple of weeks so that it develops its full flavor and stores longer.
You might want to take a look at the forum "Classifieds and Group Buys".