This is actually a tough one to answer because there are so many factors. Zone 5b would mean you could expect temperatures down to -teens as lowest temp. So you would not expect any kind of garlic growth during winter until temps range up into the 20’s low and 40’s high. In the fall, if you were late in planting and the ground froze early, then the garlic cloves may or may not have had the chance to set down roots, let alone venture to make any top growth. But more relevant is your last average frost.
So it’s not surprising to me that some of the cloves look barely growing at this point.
I WAS surprised to see your photos — the ground looks pretty dry. You must have prepped the area well or picked a particularly good location. Rainbowgardener mentioned the ground being wet — maybe hers is due to rain. Mine is still sopping wet as much from the thaw as the recent rain. I pulled the mulch away from my garlic bed last weekend I think. I can see them from my window and the tallest of them look about 4-6” I did plant “late” as well, but my last average frost is end of April, and I normally wouldn’t harvest garlic until July. Only one variety -turban type which is more suited to the south- matures a little earlier in mid-late June.
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