A changing climate impacts us all. In his latest Talking Point, Tim O’Rourke looks at how climate change affects the supply and availability of brewing ingredients

If nothing else the climate related incidents over this year will have convinced even the most scepti-cal amongst us that we are in the middle of a climate emergency, and going forward we can expect to face annual climate events such as heat waves, drought, forest fires and flash floods. 

It is incumbent on all of us to try and mitigate these events by reducing carbon emissions which im-pact on the climate, as well as affecting our lives it will also have a profound effect on the natural world around us.

Climate change also effects the supply and availability of brewing materials. This article will look at the effects on hop availability and costs. 

Hops are a perennial plant widely distributed in temperate areas and grow in many hedgerows. Hops for brewing are principally grown in the Pacific North West of America and South Central Europe, Bavaria and the Czech Republic, they also grow in the Southern Hemisphere, Australia, New Zealand, southern tip of South Africa and Patagonia.

Although the UK represents the 10th largest hop growing region, it provides most of the varieties required for brewing British beers and these hops have been affected by the hot dry spell. There are three principal effects anticipated as a result of the change in climate.

Warmer wetter winters (less snow and frost) which results in waterlogged soils. Hops have a requirement for large volumes of water, but hops don’t like wet roots and should be grown in well drained soil. Cold winters are required to vernalise (frost) certain varieties such as Bramling Cross to achieve good yield. Cold weather is also required to kill off some pests and diseases which can over winter under mild conditions.

2022 global Hop Crop

England

English hops – Hereford & Kent

Most native English hop varieties are adapted to moderate summer temperatures of between 20 – 25C. this year has seen two very hot spells with temperatures exceeding 30C which has stressed certain hop varieties such as Fuggles. By contrast other varieties such as Chinook and Cascade which traditionally grows in the Pacific Northwest of America have grown particularly well and is predicted to yield 1.5 to 2 times above their average.

The good news is that some of the recently developed hop varieties are showing good heat and drought resistance, helping us to secure a future for UK hops.

Most English hops are now grown in Hereford and Worcester where yields were normal but yields for traditional landrace varieties were slightly lower. Kent endured hotter weather and since they mainly grow traditional English hop varieties which experienced stress which resulted in lower yields but quality in terms of bitterness and aroma were good. English hop farmers may have to consider installing local water supplies for irrigation to combat drought.

United States, Pacific Northwest

The Pacific Northwest has a plentiful supply of water from the snow melt off the Cascade mountains but this year there was an unusually cold Spring and a late summer with the crop harvest a few days late with around 5% decrease in yields. With certain varieties such as Centennial and Willamette yielding well below average. The cold weather reduced the incidence of mildew, but the dry weather encourage the proliferation of spider mite. Both aroma and bitterness quality is good.

Germany – Hallertau 

Few hop farms in Europe have an independent irrigation system and hops require high volumes of water normally provided by rainfall. 

In Germany hop growers are prohibited from watering and with higher temperatures the hops were severely stressed giving anticipated yields down by 15 – 30%. The quality of the crop is good but may have a slightly lower average alpha acid content.

Czech Republic 

A similar decrease in hop crop is expected in Czech Republic town water supplies are not suitable irrigation (assuming the farmer could afford it) because most has been treated with chlorine and this can raise the chlorates concentration on the cone above the permitted standards

Slovenia

Slovenia experienced drought in previous years so most hop farmers have introduced irrigation and in spite of unusually high summer temperatures they had a normal crop.

Climate is not the only concern for hop growers. Hops are greedy feeders and require high levels of fertiliser. The prices of which have increased fourfold in cost mainly because of the Ukraine war. The other major demand is for energy required for hop drying and refrigerating hop bales in the warehouse with energy costs increasing by 3 to 4 times. Hops have never been a particularly profitable crop, requiring major investment and high labour demand and it is inevitable that there will be a substantial increase in hop costs.

Hop growers have made great efforts to reduce their energy dependence with solar power to power cold storage and have reduced the use of fertilisers using spray along with ideas such as mulching and intercropping to reduce moisture loss and pest control. The future is likely to depend on newer varieties, new hop products and inevitably higher costs.

Conclusion

u DON’T PANIC – although this year’s harvest may be below average worldwide there are still plenty of hops available from previous years and so there should not be any shortage in the 2023 brewing year. 

u There may be some carry over of the stress effect on the plant into next year’s growth which could affect availability of some varieties.

u To make sure you get the supply of hops you require all brewers should agree a contract with their hop supplier for several years in advance.

u Availability of hop varieties may be limited and more expensive so brewers may have to look for alternative bittering and aroma varieties. 

➢u The higher temperatures and low rainfall in Central Europe may result in a shortage of Noble hops for lager brewing.

➢u The increased use of hop products for bittering and aroma is generally more efficient requiring lower quantities of raw hops for their production. 

➢u Longer term, it is possible that if climate change continues, hop cultivation may need to move north from the traditional areas of the Hallertau and Washington State as temperatures in these regions rise. Late June 2020 saw temperatures in Yakima exceed 40 degrees centigrade. Fortunately, the crop was largely unaffected, but if these temperatures had occurred when the plants were at a more vulnerable physiological stage then certain varieties might have been short. 

u If nothing is done to ameliorate the effects of climate change hop will continue to be stressed with poorer yields and a scarcity in the future.

Acknowledgement: I would like to thank Andy Garbett and Will Kirby from Brook House Hops, Will Rogers from Charles Faram and Ali Capper hop farmer and Director of British Hop Association for information used to produce this article.