If you are at all clued into the craft brewing scene, you have heard of Citra. Light, crisp, and (as the name suggests) citrusy, it's one of the latest "hot" hop varieties to hit the market, and every brewer wants it. Inquiring gardeners frequently ask me where they can buy the plant, and I have to grudgingly tell them: you can't. Like many of the new varieties coming out these days, Citra is proprietary. It was developed and released by a private company - Hop Breeding Company - therefore they own the rights. You cannot buy it, grow it, or propagate it without being licensed, and to say HBC keeps that under lock and key would be an understatement. But fairly so. Breeding and releasing a single successful hop variety can take ten years minimum, not to mention tons of money. And in those years of development, breeders must keep an eye on the hop market, judging which flavors are coming in and out of style, hoping to stay ahead of the curve. Because what brewers and beer drinkers enjoy today may not be popular a decade in the future.
Breeding hops is a labor of love; an exercise in patience and perseverance. Undertaking such a project requires lots of planning and note-taking. While breeders whittle through the possible candidates for commercial release, they are continually evaluating plants and recording data for positive agronomic characteristics: above-average vigor, unique growing traits (leaf/bine color or form), pest and disease resistance, and high yields. It's a daunting task when looked at all at once, but here's a rough breakdown of how this process works...
Year 1: Breeders cross male and female plants via open or hand pollination, then collect the resulting seed. Seeds are planted in a greenhouse over the winter to grow into juvenile hops with mixed genetic profiles.
Year 2: The young plants are evaluated in the spring, with the less vigorous and more mildew-prone being tossed out. The remaining selections are planted in an experimental hop yard to continue evaluation.
Year 3: Experimental selections produce their first "baby" crop. Standouts are identified and put through sensory testing for brewing characteristics.
Year 4: The first mature crop yields continued agricultural evaluation and a second round of sensory testing. Exceptional varieties in both categories enter the fast-track to farm and brewery trials.
Year 5: Breeders propagate these exceptional varieties in the early spring, then plant them out at farm trial sites. This is their establishment year.
Year 6: The "baby" crop from the trial farm gets put into pilot brewery trials, while the mother and baby plants continue to be evaluated for agricultural characteristics.
Year 7: The first mature crop gets put through the second round of pilot brewery trials.
Year 8: Breeders evaluate the second mature crop to identify strongest candidates from the group. Any commercially-viable varieties are presented to a board for potential release.
Year 9: If a release is granted, the chosen variet(ies) can be propagated for planting and establishment on a commercial farm.
Year 10: The first commercial "baby" crop is produced.
So you can see why, after this long, tedious process, breeders play their cards close to their chest. It's a lot of money and work to get just one sellable hop variety, but sell they do. And they're not all proprietary. Most varieties produced before the 2000s (by programs like the USDA-ARS hop breeding program) are available for the public to purchase and grow. So knock yourself out! There are plenty of great varieties out there. (And we've got 17 of them!)
Hopservatory Manager, NASA JPL Solar System Ambassador