I used to get confused and wait to harvest the bulbs until the topgrowth was all brown, the way you let daffodils and tulips and other bulbs fully “ripen” before removing the foliage.
In fact, prime harvest time is when some lower leaves have gone brown but about a half-dozen up top are still green. For me that was a week or so ago; depending on the year, it can be July or August. Carefully dig one or two heads, and check to see that the cloves are wrapped nicely in papery tissue; that the heads are really ready. To get them out of the ground without damaging the cloves, loosen the soil around the perimeter of the planting carefully (not unlike you’d do with potatoes) before reaching in to dislodge the crop. Don’t just pull on each stem, because you want to cure the heads with their stems and foliage intact for best results.
With your hands, gently brush off the extra soil but do not wash the heads or dislodge the papery covering.
Plan to lay the heads on screening or hang then in a dry but not sunny spot, such as a porch or garage, where they will need several weeks of thorough drying (and as much as two months, if the season is a bit humid). A dank shed or basement is not the right place; think airy and dry. I often put mine on a heavy framed screen on top of a spare garden cart, and wheel them outside (in the bright shade–not baking in the sun, which will damage the bulbs) each
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