Plant individual garlic cloves in the fall before the ground freezes. In Chicago, this usually means by the end of October or early November. Plant cloves 6-8" apart, and around 2" deep - make sure that the tip of the clove is pointing up. It's a good idea to cover the bed with straw to help insulate the soil during the coldest parts of the winter.
The plants will emerge in the spring. At that point, be sure to provide sufficient irrigation and control weeds to grow nice sized bulbs. Don't forget to harvest the scapes once they have a full curl. Not only are they delicious, but cutting the scapes will also push the plant to focus on bulb growth instead of flowering. If you wait longer to harvest the scapes, they will be tougher (but still usable!) and your garlic bulbs will likely not grow to maximum size.
When to harvest
Garlic is a long-maturing crop, taking 8-9 months from seed garlic to final harvest. In our experience, this is usually sometime in late July through early August, but timing can vary for all sorts of different reasons. So how do you know when it's ready? It's all in the leaves.
Each leaf above ground corresponds to one layer of wrapping around the bulb. A garlic plant with 8 green leaves will have 8 layers of wrappers. When half the leaves have dried up and half are still green, it's time to start checking for readiness. Be careful not to wait until all the leaves have dried up, since the bulb won't have wrappers to protect it and the cloves will separate. While you can still eat this garlic, it won't store well.
You'll want to stop watering about a week before harvest. This will prevent rot and make harvesting easier, since the soil will be dry and loose.
Checking for readiness
Once you think it's time to harvest, clear the soil around a bulb (without digging it up) to check the size. If the bulb looks small, cover the bulb back up and check again in a few days. If the cloves look plump and the wrappers are tight, it’s ready to be harvested.
Once you're ready to harvest, do not try to pull the garlic straight from the ground by the neck. Instead, use a digging fork or trowel to gently loosen the soil around the bulbs and then lift at the base of the neck. Brush off the excess soil. Do not wash garlic after harvesting. Getting garlic wet can leave to bacteria or fungal rot.
Curing garlic really just means letting it dry out for 2-3 weeks - up to a month in high humidity. As it dries out, the wrappers will become papery, like what you're used to seeing in the store. Lay your garlic out to dry in a single layer on an elevated surface like a table or shelf in an area with good ventilation and indirect light. We like to cure our garlic in a cool basement room with a window.
During this process, avoid washing, leaving in the sun, removing leaves, or piling on top of each other. If you're short on space, you can tie your garlic in bundles and hang it to cure. You'll know it's done when the roots look shriveled and stiff and the leaves are completely dried.
Once the garlic is cured, remove the leaves and trim the roots to 1/4". Store your garlic in a cool, dry place and you'll have fresh garlic all winter long. Mesh bags, paper bags, and baskets all work well. For the longest storage, keep it between 50°F and 60°F, around 60 percent humidity, in low to no light with good air circulation.
If hardneck garlic is stored in conditions that are too dry, it can dry out. Too damp and it can get moldy. Light doesn't matter too much - just keep it out of direct sunlight. Do not put your garlic in the refrigerator as it will tend to sprout or grow mold.