Like cannabis the cultivars are usually female clones and propagated vegetatively. I purchased rhizomes from Freshops to start my crop. They produce a seedless flower and ultimately a fruit that contains oil glands that yield a variety of compounds that contribute both flavor and aroma to beer. Hops contain organic acids that isomerize during the boil and become bitter-flavored. That bitterness balances the sugars from the malt and rescues beer from being just another insipid too-sweet drink. The chemical cocktail is also bacteriostatic--hops are a natural preservative.
They are beautiful plants and do very well in our area. They take a fair bit of water but they grow like mad and have to be pruned and trained on to a trellis or framework. Commercially about a ton of hops can be produced from an acre of land. With 35,000 acres or so in the US, about 70 million pounds of hops were harvested in 2013, worth about 250 million dollars (source: USDA).
a.d. III Kal.Aug.
