Hops and climate change

At war: The breeders and the pathogens

What beer-quality hops need

Simply put, hops thrive only in moderate climates. For their well-being, they require well-drained, sandy soils with a pH of roughly 6.5 (glacial deposits are best). Because they are fast-growing, have deep roots, and a large leaf area, they need plenty of water and a balanced nutrient supply of potassium, phosphate, and nitrogen at critical times in their growing cycle, which lasts from roughly April to September in the northern hemisphere; and from October to February, in the southern hemisphere. During these roughly 120 days, hops cannot tolerate frost; and they need about 15 hours or more of sunlight per day. Yet, they also need cold, frosty winters, when the rhizomes are dormant to conserve energy. These complex requirements eliminate most of the earth’s landmass from hop cultivation, except for two narrow, lateral bands around the globe between the 35th and 55th parallel north and south.
Because the earth’s landmass is much larger north of the equator than it is south of it, the main hop-growing countries are also located in the northern hemisphere, including the two traditional hop power houses, the United States and Germany (Table 1). Other smaller hop powers are Czechia (a distant third in most years), followed by China, Poland, Slovenia, and Australia with relatively small volumes, as well as  New Zealand, Spain, the UK, France, South Africa, Canada, Ukraine, and Austria, each producing roughly 1 percent or less of the world’s hops (Figure 1 and Table 2).