This course takes me past a backyard fence on which grows a vine with deep green leaves, and large, soft-green conical flowers. Could it be?
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Yes. Hop flowers. Charlie Papazian describes them in the Complete Joy of Homebrewing as developing tiny yellow capsules of lupulin at the base of each petal as the flowers ripen, from mid-August into September. Boy and I walked there today and popped a flower off the vine, and found the lupulin. I rubbed the flower between my palms and smelled it. It's the real stuff.
Homebrew: just what I need to reduce my triglycerides.