HARVESTING AND STORING
When to Harvest
The plants are ready to harvest when the foliage has died off, or mostly died off. If it is very wet near harvest time, consider lifting them a bit earlier and drying them under cover. Left in wet soil, the outer parchment often rots. The state of the foliage is the indicator, not any particular date.
An experienced Italian American home garlic grower passes on a valuable tip for refining the estimate of when to harvest common garlic- "Once the top part of the plant has begun to turn brown, pull one of them and peel back the sheaths one at a time. My grandfather liked to wait until there were 2 sheaths, but I'm more comfortable with 3 to 4 sheaths. The problem with only watching the top part of the plant is that when it's very wet or very dry, the sheaths can reduce much faster than in other years.
When most of the leaves have turned brown (in mid-July to early August, depending on your climate), gently pull or dig up the bulbs, being careful not to bruise them. Do not leave them in the ground too long, or they may begin to separate and will not store well. Place in trays with screens or slatted bottoms and remove tops when dry. Mature bulbs are best stored under cool, dry conditions. Set aside the larger bulbs to replant later in the fall.
It is important to get the freshly-picked bulbs into the shade immediately and
to hang them in an airy place so they dry quickly and evenly.
If you intend to keep your own clove seed, select the biggest and best bulb. Leave the cloves on the bulb, and at planting time select only the best cloves to use as seed cloves. But store your seed bulbs in a relatively cool, dry place-heat in storage can cause the seed cloves to develop into a plant that produces a single large clove , rather than a normal multi clove bulb. Prolonged very low temperatures can also disrupt proper growth.