The tops or leaves of ripe garlic will turn yellow and when the tips of the foliage begins to brown this is when you should harvest. Use a large fork tool or shovel to dig up and loosen the soil under the row of garlic so you can more easily pull up the bulbs. The leaf base should look papery, but don't wait so long to harvest that the tops die and turn brown or else the cloves will have started to sprout. One more tip is to stop watering garlic as harvest time draws near so the cloves will dry out while they are in the soil. This will help the last longer in storage. Keep growing, Marianne Binetti