Where the hop is queen

Discover the most important hop garden in the world

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Wye Hops is unlike any other hop garden in Britain, and it’s perhaps the most important hop garden in the world.

Walking up and down the rows of hops, some plants are metres tall and others are chest-high, some have large leaves while others look scrawny, some bines are bright green and some are deep red. By harvest time in September, some hop cones will be short and round where others will be long and fat. Where most hop farms have a pleasing uniformity of row after row of the same variety, at Wye Hops every plant, down every single row – there are 107 rows, ranging in length from 50m to 100m – is a different hop variety.

Based on China Farm near Faversham in Kent, Wye Hops is home to the National Hop Collection and the British Hop Association’s hop breeding programme. The Collection is a living archive of selected hop varieties, both female and male – only female hop flowers are used in beer, but the males are essential for breeding – which has been added to for a century. Next to those old plants are the new ones, and young hops (mostly between one and four years old) developed through the breeding programme. These are known as seedlings.  

Where most British hop farms grow a small selection of varieties – perhaps eight to 12 – Wye Hops have 761 selected female varieties, 488 selected males, and over 5,000 seedlings, with each seedling a unique variety. For perspective, the British Hop Association website lists just 34 commercially available British hop varieties.

Every variety and seedling is grown as a pair of plants, making the National Hop Collection the Noah’s Ark of hops. It’s home to mother plants of varieties like Golding and Fuggle, there are extinct historic varieties, hops with genetic resistance to diseases, hops bred decades ago and preserved because no brewers wanted them, and hops collected from Europe and North America. All together this represents the past of British hops, and it will also define the future. 

THE NATIONAL HOP COLLECTION

The archive of selected varieties is the foundation of the National Hop Collection. “We’d like to think that every characteristic you might want from a hop is in this garden,” says Mike Baldock, Wye Hops’ Plant Breeding Technician. “There are high-alpha varieties, high resin content varieties, there are Fuggle-type varieties, Golding-type varieties, there are varieties that smell like old socks, there are varieties that smell like flowers,” he says. “There’s a complete kaleidoscope of flavour.” 

The collection has existed for over 100 years, connected to the breeding programme which started at Wye Hops (previously Wye College) in 1906 by Professor Ernest Salmon. Since then, the collection of hops has been growing, with old varieties safely banked for prosperity, and new ones added whenever they are discovered.


The breeding programme has given us some of Britain’s best-known hops, including Bramling Cross, Challenger and Target (Fuggle and Golding are landrace hops, meaning they naturally developed and weren’t bred). There have also been hundreds of varieties bred by Salmon and his successors which had positive attributes but for whatever reasons didn’t suit the market at the time. Rather than composting them, many were kept alive in the collection and grown back every year.  

“It’s about maintaining a collection of germplasm that’s got a wide range of qualities that may not necessarily be required today,” says Baldock, “but we’re maintaining them just in case.” That ‘just in case’ has become relevant in the past few years as taste preferences and breeding priorities have changed.

“The whole purpose of plant breeding [is] to improve upon a variety,” says Klara Hajdu, Trainee Hop Breeder at Wye Hops. Historically that meant trying to breed similar flavours to existing hops but with better agronomics, so hops were assessed for how true-to-type they were (does it smell like Fuggle, Golding, etc), plus how well it grew and its resistance to disease. Brewers didn’t want new flavour, but they do want new flavours now, and they want something to suit modern beer styles. The British Hop Association wondered whether there might be something in the National Hop Collection that brewers would like. 

GOING BACK TO THE FUTURE

Prof. Salmon’s first successful crosses – Brewer’s Gold and Bullion – achieved his pre-determined goal: producing an English-grown hop with a higher resin or alpha acid content (which helped beer last longer, and gave a more efficient bitterness – i.e., fewer hops needed for the desired bitterness). Salmon crossed English females with wild North American males and while they took a higher resin value from the males, they also inherited a distinctly American character – pungent blackcurrant and citrus – which was undesirable to British brewers.

In the following decades, more crosses were made with Brewer’s Gold, Bullion, and wild American hops, and that strong American character continued to come through, so many promising varieties were deposited into the hop collection and forgotten about.

Around 10 years ago growers began reassessing those older varieties in the National Hop Collection with a new priority – intense aroma – and they discovered varieties with great potential, plus they rediscovered important old varieties, like Bullion.

Bullion was released as a high-alpha hop in 1938 but it ended up being grubbed from fields in the 1980s and wasn’t grown for 25 years until Ross Hukins, Director of the British Hop Association and grower at Hukins Hops, went into the National Hop Collection and took cuttings from it. 

Hukins is the fifth generation to run his family business. “My grandfather grew [Bullion] here and it was my father’s idea to plant it again,” he says. The initial cuttings became 100 plants, then 1,000, and now it covers several acres. Where it used to be sold as a bittering hop, Hukins sells it as an aroma hop with its punchy aromas of orange, lemon and tangy blackcurrant. Those aromas were always there, it just needed growers and brewers to think differently about them, and to utilise them in new ways. 


Other varieties have also been rediscovered or remarketed, like Admiral (orange, resinous), Bramling Cross (blackcurrant, spice), Keyworth’s Early (lemon, grapefruit), Pioneer (grapefruit, cedar) and First Gold (marmalade, orange).

Then there are the hops which never made it to commercial scale, and which were preserved in the archive. There was one variety which “kept being noticed as being interesting,” says Hukins, for its distinctive apricot, citrus and spice character. It had been bred by Salmon and had wild American heritage, but was too aromatic for brewers of the day, so it was left in the collection with a note suggesting ‘no obvious promise now,’ perhaps with emphasis on the now. As growers and brewers successfully trialled it, it was planted up to commercial scale and came to be named after its breeder: Ernest. Hukins Hops is now one of its main growers.

“I think it’s nice that [Ernest] resided quietly in the background without anybody noticing it for so long,” says Baldock. “And also that we kept it: we didn’t think ‘no, we’ll get rid of it, it’s got no purpose,’ we kept it because it might have a purpose.” There are several other hops like Ernest which are currently going through more trials and showing great promise, while there’s a renewed interest in extinct varieties like Early Prolific, Tolhurst, and Colgate.

It’s unlikely that a decade of annual searches through the archive collection has discovered anything particularly appealing for right now – though there may be others which will appeal to new and different tastes in the future – and so, as Ali Capper, chairman of Wye Hops (and hop farmer), says, now the National Hop Collection’s “real value is in breeding for new varieties.” 

THE BREEDING PROGRAMME

The National Hop Collection is “a brilliant resource to be able to dip in to, to make sure we’re always selecting the right parent for whatever our breeding objective is,” says Capper. Past priorities have been higher resin content, disease resistance, and replacements for varieties like Fuggle which are susceptible to verticillium wilt. Now Capper explains that the breeding project is for intense and interesting flavours which are also recognisable (so when you smell the hop in a beer, you immediately identify something like mango or peach).

Around 30 crosses are made each year, meaning a selection of females are pollinated by a selection of males, which Hajdu and Baldock choose from parents from the existing hops they have growing on the farm – Ernest and Cascade have been common females in recent years, while the males are picked more by habit and through knowing they can provide good agronomics. The result will be some 700 seeds per female, which are essentially 700 siblings with shared parental DNA but totally unique characteristics. Each individual seed could become a new hop variety. The challenge is finding the good hop, and hoping that it grows well.

From those 30 crosses, some 15,000 seeds will move into a glasshouse. They’ll be infected with downy mildew and then powdery mildew, which will leave around 1,200 seedlings. They go to the field to grow, where, after three or four years, they can be properly assessed for flavour and growers will rub the cones in their hands, and have a good sniff. Any hops which display potential are kept for further trials.In a good year, that’ll be around 30 females. The most promising six or seven of those will be grown further, and perhaps two or three will be trialled on other hop farms, though it’ll be at least another five years before it’s available at commercial scale – and that’s only if it passes all disease resistance tests (especially wilt which can only be tested on a mature plant), and grows well and harvests well – no matter how good a hop smells, if it doesn’t grow well then it’s not a viable variety.


There are currently around a dozen varieties at different stages of field trials. It’s not easy – or quick, or cheap – to find new hops. But finding new varieties is essential: “The only future for hop growing in this country is to produce varieties that brewers want to buy,” says Baldock. “Breeding new varieties of hops has never been more important.”

Brewers want high-intensity hops, which they’re buying from America and the southern hemisphere, because they work best in the popular contemporary styles, like IPA. As those styles increase in popularity, traditional ones like Mild and Bitter, which use traditional British hops, are declining in volume, meaning those hops are not being bought. Hop farmers need British-bred varieties, which grow well in our climate and soils, which brewers want to buy (there’s also the key considerations of climate change, sustainability and using locally-grown produce, which are critically important but beyond the scope and word count of this story).

And complementary to the British Hop Association is another breeding programme with similar ambitions.

JESTER, HARLEQUIN & MYSTIC

Charles Faram are a grower-owned hop merchant and have been running their Hop Development Programme for a decade. Through their early successes they’ve released the proprietary sister varieties of Jester and Olicana, which have citrus and tropical qualities. Now Jester is being used as one of their main breeding hops.

Harlequin and Mystic are the next hops to look for. Harlequin – with pineapple, peach and passion fruit aromas – was fast-tracked to field trials as quickly as possible because of the promise it showed and, as Paul Corbett, Managing Director of Charles Faram, says, “we know that we’ve got other varieties coming through which are even more intense,” with more tropical fruit, bubble gum, pomegranate, mango, tangerine, and more.

Charles Faram are investing more into their programme and are excited that with each successful new cross there are new intensities and aromas. “I never expected to get to the level we’re at now,” says Corbett. “We don’t know how far we can go yet,” he says, but they’re going to keep on trying: “The more you look for it, the more seeds you make, the more crosses you make, the more likely you are to find that needle in the haystack,” says Corbett. And the next development for British hop breeding will hopefully make that metaphoric needle a lot easier – and quicker – to find. 

THE DNA OF HOPS

Klara Hajdu is completing her PhD research into genetic markers for hops, trying to find the specific DNA responsible for certain traits. “We have all this genetic material but we understand too little about it,” she says. “We need to understand more. We have to utilise it better.” By looking at a molecular level, the whole breeding process can become more accurate and efficient.

The first markers Hajdu is searching for are resistance to verticillium wilt and downy mildew. Finding hops with resistance means she can breed with them (still using the traditional methods), increasing the chances that seedlings will also have that resistance, and future generations will all carry that, speeding up the screening process.

While finding the genetic marker for disease resistance is the first challenge, the search for flavour is harder. Alpha acids and the aromatic oil content “could be controlled by many genes, plus the environment will impact it. So that’s harder to figure out with sequencing,” says Hajdu, “but you can get a good idea because there are some things in the DNA which can give a good estimation.” That might mean finding markers for certain hop oils or proportions of hop oils as an indicator, but all hops will still be assessed with the rub and sniff technique. “I don’t think we’ll ever get rid of the need of the breeder’s eye,” says Hajdu. “The human factor is massive in breeding. I can’t quantify that with markers.”

Come September, the first assessments can be made on the three- and four-year old seedlings at Wye Hops, plus another walk through the National Hop Collection, just in case they’ve missed anything. The growers will rub the hops between their hands and hope for something interesting. No one knows quite what they’ll find, but those warm harvest weeks always bring a lot of hope and excitement, and by then, some of Hajdu’s Doctorate work can be properly evaluated in the hope of modernising a century of hop breeding.

“Everything we need is probably right there,” says Hajdu, looking over the hop garden. “We’re still at the beginning of this whole story.”

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