I believe that the greens start to yellow and then turn brown. This is usualy when they get pulled or dug up. But I am not an expert, so I might be wrong

We are starting garlic harvest today in NC (piedmont area ) but not all varieties.
Yes Yellowing and browning leaves are normal.
The falling over is normal also.
We harvest when about 1/2 of the leaves are brown or the whole plant is yellowing. Best to harvest a little early than late. It is best to get it up in dry conditions. With softnecks especially when you want to braid some it is wise to get them up early. Check each plant harvest the ones that are ready and leave any that are mostly green and harvst them later.
Good Luck
The Garlic Lady

Thanks Garlic Lady! I see your posts all over this forum and feel that I have been advised by somewhat of a regional hero! I have been consulting "Growing Great Garlic" by Ron Engeland and just this weekend dug most of the garlic and it is now drying in the shed under the slow speed of a ceiling fan. Some of the plants did not produce multiple cloves and some did. The plants that had no green left in the follige had some of the cloves exposed. I plan to do more reading and soil prep next year and really smoke next summer!

Best to harvest a little early than late.

uh oh. glad I saw this. Not that I need much encouragement.. I'm just DYING to get at those bulbs. They've been teasing me all spring!

Not to worry. If you harvest late they are still good but since the paper wrappers break down they dont store as long. Just use them up first.

Taste just as good.

Warthog