American craft beer drinkers might be forgiven for believing that the history of New Zealand hops didn’t begin until Nelson Sauvin started appearing in their IPAs in the early 2000s. But the truth is that the New Zealand hop industry dates back almost 200 years, and has often been a world leader in breeding and environmentally-friendly agricultural practices. Let’s learn more about Humulus lupus in the Land of the Long White Cloud:
In 1840, the Treaty of Waitangi gave Great Britain sovereignty over New Zealand and paved the way for immigrants from the UK and other parts of Europe to settle there, bringing along their native beer culture.
Hops grow best between 35° and 55° latitude worldwide, and English and German colonists who settled on the south island discovered that hops grew very well there.
Nelson, named after the British naval hero Admiral Lord Horatio Nelson and situated along the 41st parallel south on Tasman Bay, became the center of hop production in the new colony. By the end of the 19th century, the Nelson area boasted 19 breweries.
20th Century: Changes and Innovations
Cluster hops were brought from the west coast of the United States to New Zealand hop gardens in the 1920s. Known as California Cluster, Late Cluster, or just Cali, its hardiness and yield made it very popular with New Zealand growers. Unfortunately, it also proved susceptible to Phytophthora, or black root rot.
By the 1940s, Phytophthora had become an existential problem for the NZ hop industry. The New Zealand Brewers Association funded a hop research program to combat the threat posed by black root rot, and established a research station in Riwaka.
Enter Dr. Rudi: R.J.H. Robrogh, a Dutch-born scientist who arrived in New Zealand after a stint in an Indonesian prisoner of war camp, pioneered several new hop cultivars that were both resistant to root rot and high yielding to boot. Smoothcone, First Choice, and Calicross were developed in the 1950s and introduced to hop gardens by 1960.
After saving the New Zealand hop industry from Phytophthora, Dr. Rudi (these days also known as “the father of New Zealand hops”) turned his attention to another problem: the worldwide demand from brewers for seedless hop flowers. At that time, most other hop-producing countries simply purged male plants from the hopyards and crossed fingers. Dr. Rudi took inspiration from polyploids.
According to the Nelson growers’ cooperative New Zealand Hops Ltd.:Seemingly extra-terrestrial in name, polyploids, including tretraploids and triploids, are simply multi-chromosomal plants which produce virtually sterile seedless fruit yet retain the elemental flavor and composition of the parent.
Robrogh guided an intensive breeding program with the goal of seedless hop cones that retained the aromatic oil profile and alpha content of the parents. Thanks to his work, New Zealand gave the brewing world its first triploid hop plants. In the past 40 years, the New Zealand hop breeding program has released 19 triploid cultivars.
Thanks to a growing environment that is virtually free of the hop diseases and pests that afflict the northern hemisphere, New Zealand is the world’s largest producer of organic hops.
The only exception, according to New Zealand Hops Ltd., is the two-spotted mite; and a natural solution, in the form of a second mite that preys on the two-spotted, has been implemented, so that hop gardens can remain pesticide-free. Instead of sprays, Nelson growers graze sheep in the hop gardens to defoliate the lower part of the plant naturally and mow the cover crops in between the trellises.
The environmentally-friendly practices continue through harvest as well: New Zealand Hops Ltd.’s hops are dried using hot water radiators as the source of heat, thereby ensuring the hops stay free from any contamination by exhaust gases.
Coming to America
Upon its release in 2000, Nelson Sauvin made a big splash with American brewers, who quickly made a home for it in everything from IPA to saison. Craft beer consumers wanted more and the way was paved for other new and traditional New Zealand varieties.
The intensive work started by Dr. Robrogh has flowered (pun intended) into the multitude of varieties available to brewers today. By incorporating Old World genetics into New Zealand’s hop breeding program, New Zealand growers have created a wide range of flavor profiles, from the spice-and-fruit of classics like Dr. Rudi and Green Bullet, to the intense tropical notes of new cultivars like Rakau and Moutere.