How long have British brewers been using American hops? Far, far longer than you might have guessed: for around two centuries, in fact.

The earliest evidence I’ve collected so far of hops from the United States in England is from exactly 196 years ago: May 1817, when the Liverpool Mercury newspaper carried a notice of the arrival in the city of a ship from New York, the Golconda, carrying 417 bales of cotton, 319 barrels of flour, 1,322 barrels of turpentine – and two bags of hops. Rather more came across the Atlantic a few months later, in November, when two ships arrived, the Pacific from New York and the Triton from Boston, with cargos including 49 bales of hops and 30 bags of hops respectively. An even larger consignment, 185 bales (a bale being 200 pounds), arrived the following month, December, from Boston on board the ship Liverpool Packet.

Not coincidentally, these imports of hops from the United States were arriving in Britain right after the famous (to climatologists) Year Without a Summer of 1816, itself the result of the biggest volcanic eruption in recorded history (with the possible exception of the putative proto-Krakatoa), when Mount Tambura in Indonesia blew up on April 10 1815 with a roar heard 1,600 miles away, sending 50 to 100 cubic kilometres of rock into the air and dumping tens of millions of tonnes of sulphur and ash into the stratosphere via a column of smoke and fumes 27 miles high, covering the northern hemisphere in a sulphate veil. Temperatures in North America and Europe dropped by as much as 3C for at least two years, rainfall rose by as much as 80 per cent, and agriculture was badly hurt.

The year after the eruption, the hop harvest in Britain, in particular, was hammered. Newspapers from September 1816 onwards engraved a picture of misery. The Hereford Journal reported that locally “the hops have nearly all been destroyed by the inclement season.” At Worcester fair, the Morning Post said, “there was not a pocket of new hops”. At Stourbridge Fair, just outside Cambridge, normally one of the country’s biggest hop marts, “the supply of hops was very small, not more than half a load.” In Farnham, Surrey, the hop cones were “uncommonly small”, and the harvest was set to be no more than a quarter of its usual size. At Weyhill fair in Hampshire in October just over 700 pockets of hops were on sale, down from 3,000 the previous year.

The final harvest was just under 100,000 hundredweight of hops, against 265,000 hundredweight the previous year and an estimated annual consumption of around 210,000 hundredweight. By December the shortages were being reflected in the prices being charged at the hop market in Southwark: £10 to £15 a hundredweight (112 pounds) for Sussex hops, £10 10 shillings to £17 for Kents, and £18 to £25 for Farnhams, all two to three times more than the prices being charged the previous year.

Normally foreign hops were kept out of Great Britain by a deliberately crippling rate of duty: in 1711, when a tax of one penny a pound (nine shillings and fourpence a hundredweight) was first laid on British hop producers, the “protective” duty on foreign hops imported into Great Britain was set at three times as much, £1 8s. (Foreign hops were banned from import into Ireland entirely, unless and until, at least in the early 19th century, British hops reach £9 a hundredweight.) Over the following century the duty on foreign hops rose to £5 18s 10 pence a hundredweight in 1787 and, by 1818, £8 11s. The tax on home-produced hops, meanwhile, had merely doubled, to 18s 8d a hundredweight.

The result was, effectively, a bar on the import of foreign hops, except, as happened in 1800, when there was a severe shortage and the government was persuaded to drop the tax on imported hops temporarily down to the same level as that on the home-grown variety, or, as in 1817-18, when the prices being charged for home-grown hops in Britain were so high that the import tax on foreign hops scarcely mattered.

Even then, however, American hops were at a disadvantage over hops from Flanders, Bavaria and elsewhere in Continental Europe, because British brewers did not like their flavour. In September 1819, Richard Rush, the United States “Minister Plenipotentiary” (ambassador) in London, visited Truman’s brewery in the East End, and asked the man showing him round, “young Mr Hanbury” (presumably Robert Hanbury), if “they ever got hops from the United States.”

“The answer was, only in years when the crop was short in England, the duty upon our hops being so high as to amount to prohibition. The price in England for their own hops was stated to be £3 per hundredweight, this was in good seasons: last year, being a very bad one, the price rose greatly higher. This had brought American hops into demand, the quality of which was better for brewing than the English, but it was said that they were injured for the English market by being dried, as was supposed, with pine wood, this being the only way in which a bad flavour imparted to them could be accounted for.”

Hanbury’s comment about American hops tasting as if they had been dried with pine wood is fascinating and revealing, since it looks to be the first ever reference to the “piney” aroma associated with some of today’s American hops, such as Chinook and Simcoe: an aroma that, along with others found in many popular hop varieties, is almost certainly derived from native American wild hops in the ancestry of American cultivated varieties. The oil that is associated with “piney” flavours in hops is myrcene, which also gives floral and citrussy flavours: wild American hops are particularly high in myrcene compared to European types. So, too, are most varieties of cultivated American hops.

You will sometimes see it asserted that hops were “introduced” to North America in the early 17th century by Dutch and English settlers. In fact, when Europeans arrived, there were already three native North American hop varieties growing across the continent, where they had been for around a million years, after migrating from Asia: Humulus lupulus var. neomexicanus, which as its name suggests, grows in the Rocky Mountains area, from the Mexico border to Saskatchewan; H lupulus var pubescens, which is found in the mid-western United States; and H lupulus var. lupuloides, which grows on the eastern seaboard from New Brunswick to the Mason-Dixon Line, and right across to the Dakotas and Manitoba.

Pubescens does not seem to interbreed with European hops (which has led to the suggestion that it should be classed as a different species, rather than a variety), but neomexicanus and lupuloides can interbreed and have interbred with European types, both accidentally and with deliberate human assistance. Indeed, today it looks as if few or no “American” hops are free from wild American hop genes. Dr Ray Neve, director of hop research at Wye College in Kent, writing in 1976, said:

“There is no doubt that the early American settlers took hop cuttings with them, but the characteristics of the present-day American cultivars indicate with some certainty that they developed as a result of hybridization between the introduced and indigenous plants.”

It looks as if, judging by Hanbury’s comment to Rush about the “pinewood” flavour of American hops, cultivated European hops had already interbred with native types in North America by the start of the 19th century (and probably much earlier): presumably the lupuloides variety that the first settlers in and around New England would have found growing in the woods and valleys near their farms. Genetic studies have shown that Cluster, one of the oldest varieties of American hops, is a mixture of native and European hops, presumably created accidentally.

In the past hundred years, interbreeding between wild American and cultivated European hops has been conducted on a more scientific basis. Brewers Gold and Bramling Cross are just two varieties created deliberately by crossing a European variety with a wild hop from North America, in the first case a wild female from Manitoba and a male English hop, in the second a wild male hop from Manitoba and a female Bramling hop (a Goldings variety) from Kent. Both the lupuloides and neomexicanus varieties are found in Manitoba, and nobody seems certain which of those two were the “wild side” parents of Brewers Gold and Bramling Cross. Quite possibly, in fact, the wild parents were themselves crosses between the two North American varieties. Rather more randomly, Cascade, frequently described as the most popular hop with the US craft brewing industry, was born in Oregon in 1956 (but not release until 1972) in a breeding programme via open pollination of a female plant of more-or-less known European lineage by a male parent of unknown provenance which later studies strongly suggest was of wild American origins.

One other interesting point arises from Hanbury’s comments to Rush: if the dreadful harvest of 1816 (and 1817 was not much better, at barely two fifths the size of 1814’s crop) “had brought American hops into demand, the quality of which was better for brewing than the English”, then were American hops used during the shortage of English ones to make pale ale for the Indian market? In other words, were American hops being used to make IPAs (which weren’t then known as IPAs, of course) two centuries ago?

Well, with the enormous caveat that we don’t have any evidence for it whatsoever, yes, it’s distinctly possible that in 1817 and 1818 the brewers shipping pale ale to India from England used some American hops in that pale ale because they couldn’t get enough English ones. Indeed, it verges on the probable that some foreign hops, from North America or continental Europe, went into ales and beers shipped to India in those years, simply because poor harvests meant the supply of English hops was so much smaller than the demand. In 1817 and 1818, almost 52,000 hundredweight of foreign hops were imported into Great Britain to make up for the poor British harvests. The Hodgsons at the Bow brewery, a few miles east of Truman’s, who were still at this time the main suppliers of pale ale to India, would have had just the same problems that Truman’s and everybody else had in buying sufficient supplies of hops after the harvest collapsed in 1816, and may well have welcomed hops from the United States, with their higher bitterness, regardless of their aroma. So American hops in IPAs may have an ancient pedigree.

However, British brewers generally continued to avoid American hops except in times of shortage. British comments about American hops frequently used the adjective “rank” to describe their aroma, which a writer in the Edinburgh Review in 1862 blamed on “the soil in which they grow”. Was this “rank” smell and taste that British brewers so deprecated the “catty” aroma many find today in American hops such as Cascade, Cluster, Simcoe and Eroica (descended from Brewer’s Gold via open pollination)? If it was, then, it’s (1) another example of the antiquity of certain kinds of flavour in cultivated American hops and (2) almost certainly another of the characteristics derived from American cultivated hops’ wild neomexicanus and/or lupuloides sides of the family.

At any rate, deterred by the enormous duty payable, imports of hops into Britain, American or otherwise, remained extremely low. In 1827, just four hundredweight of foreign hops came into the country. In 1833 barely 100 hundredweight of foreign hops arrived, all from the Hanseatic Towns (that is, probably, grown in North Germany), while the next year just 470 hundredweight of hops were imported, only 136 hundredweight of it from the United States, to be set against 14,800 hundredweight of British hops exported abroad. (Most of that year’s imports, 223 hundredweight, came from Denmark – who knew? – while Canada managed to supply 104 pounds, which seems hardly worthwhile.) American hops were also finding their way onto the Continent, incidentally: in 1834 the American Railroad Journal reported that “A gentleman from Germany informs us that American hops have been tried in that country and obtained a decided preference to the English; and that an increased demand from that quarter may be looked for hereafter.”

In 1842, as part of the general movement to cut tariffs that culminated in the repeal of the Corn Laws, the tax on imported hops was almost halved, to £4 10s. Although, as the Prime Minister, Sir Robert Peel, recounted, “The hop-growers of Kent and Sussex said, ‘We shall be ruined: where are those employed in the culture of hops to find subsistence?'”, in the next four years only two hundredweight of foreign hops entered the country. In 1846, the same year the Corn Laws were abolished, the tax on foreign hops was cut again, to £2 5s. According to The Transactions of the American Agricultural Association, published that year, this was down to pressure from British brewers keen to import American hops precisely because of their strength:

“Last year two bales of New York grown hops were sent to London as a sample; a committee of brewers was appointed to examine them, and they arrived at the conclusion that these hops were fifty per cent stronger in aroma than those of England. The committee waited on Sir Robert Peel with this conclusion, and in the new tariff a decrease of the duty to just one half or £2 5s per 112 lbs, is proposed. A reduction of the duty has been advocated in England for a long time, on the ground that a diminution in the cost of hops would induce the brewers to use nothing else in their malting; but the protective agricultural interests have as yet proved too strong for the manufacturers. It is believed that with the proposed reduction of duty in England, this article will become one of the principal articles of export from this State; indeed, farmers in this State have, in anticipation of it, already laid out grounds enough to increase the export thirty-three per cent within two years. The average product, per acre in England, according to the London Mark Lane Express, is for the last twenty years, less than 500 pounds per acre, while the average of the American harvest is 1400 pounds per acre.

Once again the English hop growers declared that the cut “would ruin all the landowners, tenants, and labourers of Sussex and Kent, and throw thousands out of employ.” But while imports from both Europe and America certainly rose, evidence given at a parliamentary inquiry into the hop duty in 1857 suggested that every year the quantity of hops imported into Great Britain was more or less balanced by the quantity exported. The only year that American hops were imported in any quantity was after the failed harvest of 1854, when the import duty was again cut to the same level as the tax on domestic hops, and enough hops were brought in from the US (which sent 18,000 hundredweight) and Belgium to drive down the price of poorer quality Sussex hops by half.

Several witnesses to the 1857 inquiry commented adversely on the quality of American hops. Thomas Waterman, hop merchant, said:

“I should say that the American hops would never come into use in England for brewing purposes on account of the flavour, which arises pretty much from the soil on which they grow. I made an experiment with them upon my kilns in Kent to see if I could destroy the flavour, but it is impossible to do so by any sort of process whatever; it retains the same flavour, and we cannot get rid of it. I do not believe that they will ever be able to come into use.”

Robert Tooth, a hop grower in Kent (and brother to the founder of Tooth’s brewery in Sydney, Australia), said American hops were “grown too rank; they are very powerful in their flavour, and very bitter, they are naturally grown of a certain quality, which cannot be changed, by reason of the soil and climate being the only cause of it.”

The main importers of American hops seems to have been a firm called Keeling and Hunt, with offices in Monument Yard in the City of London, which commissioned a report on the US hop trade in 1847, reprinted in Berrow’s Worcester Journal. Their American correspondent described the “eastern hops”, grown in Massachusetts, Connecticut, Vermont, Maine and New Hampshire, as

“[resembling] more in colour and flavour the English hop than any other grown in our country. For strength and flavour they cannot be equalled by any thing grown in your country … I understand that some of your brewers in the city of London have condemned our hops for the reason that they are too rank and strong … I confess our hops are stronger than yours, and to avoid the evil complained of, or to remedy the great objection made, let the brewer take two pounds of the American where he at present uses three pounds of the English, and he may rest assured of producing as full and fine an aromatic flavour upon his ale, to say the least, as he does now. The quality of the eastern hop this year is uncommonly fine, … if your pale ale brewers could be induced to give this article a full, fair and impartial trial, I have no question they would prefer them.”

Of the “western” hops, “those grown in the western part of this state” (presumably New York state: it would be another 20 years before hops were grown in the western US, although in 1846 it was said that some hops “of inferior quality are raised in Ohio and Indiana”), Keeling and Hunt’s correspondent declared: “For certain characters of ale, and for brown beer and porter, there are no hops grown in the world to compare to them … Our western hop is much stronger than our eastern, and is used almost invariably by our porter and brown ale brewers, and for the manufacture of stock liquors.” (The statistics for 1845, incidentally, showed the New England states growing 4,250 bales of hops, and New York 4,000 bales).

Despite the threat of foreign competition, however, starting in 1860 the English hop growers themselves allied their regular agitation for an end to the domestic tax on hops with a call for the abolition of the duty on foreign hops as well. This seems to have been prompted by a feeling that the free trade sentiments of the then government would not have scrapped the domestic duty without ending the duty on imports as well. At first the Chancellor of the Exchequer, William Gladstone, resisted the hop growers’ calls, probably because in the last half of the 1850s the hop tax had brought in record revenues, culminating in almost £400,000 being collected in 1859.

Inevitably, however, 1860 saw yet another dreadful harvest. Gladstone had predicted in his budget for 1860, set in the spring, that the hop tax would bring in £300,000 that year. In the end the take was less than £70,000. The next year was again poor, with a domestic tax take from hops of just £149,000. Prices by December were up around £9 a hundredweight, and “large” quantities of Belgian, Bavarian and American hops were being imported to make up the shortfall: large enough quantities so that a big fire in Tooley Street, Southwark in the summer had seen 5,000 bales of American hops destroyed.

Gladstone, one of the smartest operators in British political history, saw a way to make it look as if he was doing the English hop growers a favour, and at the same time end the wild swings in revenue represented by the hop duty. Even better, he could also secure the same or more tax income. For his 1862 budget, he announced that he would, indeed, be ending the hop duty, on both domestic and foreign hops: but he was putting up the cost of a brewer’s licence by three pence per barrel of beer produced. That three pence a barrel represented the former tax on the two pounds of hops that was, Gladstone told the House of Commons, the minimum that went into a barrel of beer. He also introduced, for the first time, a licence for home brewers, who would now have to pay 12s 6d a year if their rent was greater than £20 a year for private home owners (maybe £1,300 a month today), or £150 a year for farmers. At a stroke he had turned a wildly variable source of tax income into a steady one without offending too many people.

By 1889, despite the previously poor reputation that American hops had had for flavour (even in 1875 one commentator called them “strong, coloury [but] badly flavoured”, a spokesman for Bass could tell the Pall Mall Gazette that while the best hops came from Kent, “there are none to equal them in the world”, “The Americans, however, are greatly improving in their cultivation of hops, and some very fine ones come from the north-eastern states.” The spokesman also revealed that Bass used no Bavarian hops at all.

American hops were now divided in the UK market into “States” and “Pacifics”, with hops from Washington, Oregon and California all available at the hop market in the Borough. Hops from the US continued to arrive in Britain in considerable quantities: in 1908 yet another parliamentary inquiry into the hop industry (there was also one in 1890) was told that half the hops imported into the UK came from the United States, and 90 per cent of US hop exports went to Britain (with much of the rest going to Canada, Australia and India.) Until around 1905 most of the American exports of hops to the UK came from the Atlantic states, with increasing amounts then arriving from the Pacific states, notably California.

The introduction of prohibition in the United States gave the American hop industry a massive incentive to increase its exports, of course, and in the three years 1920-1922 more hops, many of them American, were imported into the UK than were grown by English hop growers. The howls of pain from the English growers were eventually met by the imposition in 1925 of a £4 a hundredweight tax on imported hops, which, except in years of poor English harvests, pushed imports of hops down to minimal levels: by the early 1950s hops imports were down to less than 1 per cent of total UK hop usage.