500 Years of Oasts and Hop Kilns in England

The introduction of hops for brewing in England

As little as sixty years ago many hundreds of brick and timber hop kilns and oasts were still used to dry hops. Now very few remain in use.

Hops are an essential ingredient in the production of beer, helping to preserve the beer in good condition and give it a bitter flavour.

Imported hops were introduced in London in the 15th Century, to brew bittered beer instead of the traditional unhoped ale common in England. The growing of hops in Kent was introduced by Huguenot Refugees during the Reformation. The first documentary evidence of oasts built to dry hops in England appears soon after.
Hop-drying buildings are called oasts in Kent and Sussex and hop kilns in Hampshire, Surrey, Hereford, and Worcestershire.

There are about 1500 hop-drying buildings on Historic England’s National Heritage List. Oasts and hop kiln spread across the landscape until the late 19th Century when England was the world’s largest producer of dried hops. A recent Historic England/Liverpool University Press book (2021) gives us the first national account of this special branch of vernacular architecture, drawing on regional studies in the last 60 years.

The function of hop drying

Oasts and hop kilns consist of a rectangular building of from one to three storeys, called a “stowage”, with a kiln or kilns (up to six) attached to it. A hop kiln had to be close to the hop farm to permit rapid transfer of the crop from field to kiln. Otherwise humid “green” hops decayed and were ruined.

The hops were first typically taken in to the upper floor of an oast or hop kiln and spread on a slated drying floor in the kiln for ten hours, heat being provided by a furnace below. This reduced the humidity from over 80% to less than 20%. The hops were cooled in the stowage and then tightly pressed in large “pockets” for despatch to a market or brewery.

The geography of oasts and hop kilns

Small-scale, local hop growing spread rapidly to many counties of England, mainly in the south and east, up to Nottinghamshire and down to Dorset. Recent research published by the Essex Society for Archaeology and History has used place names to map otherwise unsuspected hop growing and drying in the 17th and 18th centuries in that county. Attempts to develop a hop industry in Scotland, Wales and Ireland were defeated by the weather and topography.

Over time, the industry became concentrated in three favourable regions: Kent/East Sussex, Hampshire/Surrey and Herefordshire/Worcestershire . The buildings in each area had a strong regional identity. By the later 19th century, Kent was producing 75 per cent of England’s dried hops. In the present century, West Midlands production has overtaken Kent and Sussex for the first time.

Research into oasts and hop kilns.

This topic is multi-disciplinary. The new Historic England book is based on studies conducted in1960, updated 60 years later. In the intervening years several experts have researched the history of hop drying in greater detail. Robin Walton in Kent, David Martin and Gwen Jones in East Sussex, Edward Peters, Joan Grundy and Jennefer Wheale in the West Midlands made important regional studies based on fieldwork evidence. When I returned to write the book their work and online sources contributed greatly.

Studies of hop farming, hop picking, marketing, transport, and brewing are all necessary to understand hop drying. Brewing has long attracted a wealth of excellent writing. All this work has provided a more solid context for the study of how the industry’s buildings evolved.

Major libraries, including Historic England’s, contain an exceptional body of illustrated literature and manuals on hop farming, from the mid-16th Century through to the present day. Gentlemen farmers and landowners put on record illustrated instructions on the best way to grow and dry hops.

Hops were the most profitable, most risky and most volatile product of English farming, generating much passion between the participants.

The study of hop drying buildings has also benefited from the growing discipline of industrial archaeology and its focus on technological innovation. Surviving buildings retain much evidence of how new methods of heating and draught control were introduced: ultimately the installation of electricity in kilns made drying far more efficient, but led to the scrapping and loss of many earlier furnaces.

The evolution of oasts and hop kilns

The earliest known oasts were square or rectangular structures inside a farm building which otherwise looked like a barn or shed. However, they contained a drying floor and a kiln. These “inset kilns”, that is, kilns within the structure of the building, are hard to trace from the exterior and therefore it is difficult to estimate with any confidence how common they once were.

Square and round kilns

The new scale of production encouraged the development of oasts and hop kilns in which kilns were built grouped around the stowage, rather than within it. Square pyramidal kilns developed before round kilns, but in the late 18th century John Reid from the Weald of Kent emerged as an indefatigable campaigner for the merits of round kilns. The roundel became the dominant type in Kent and Sussex, though not in the West Midlands or Hampshire, where the square kiln remained the norm. About 50 years later collective wisdom shifted again and square kilns became dominant in the final years of hop kiln building.

Cowls

White-painted wooden cowls revolve on a vertical spindle at the top of the kiln, turned by a long wind vane so that the open side faces down wind. They expel the fumes and humid air from the kiln and shelter the drying floor in bad weather. They are the most prominent symbol of hop country.

The 20th century

English hop farming declined throughout the 20th century, falling to 1 per cent of world production. As a result, thousands of oasts, especially in the Home Counties fell out of use. However, the decline coincided with strong demand for rural homes of character within reach of London. Former oasts, converted to residential homes now sell for £1 million upwards. Conversions to dwellings are less common in the West Midlands.

Former oasts, converted to residential homes, now sell for £1 million upwards.

The survival of historic oasts and hop kilns in south-east England has therefore been greater than might have been the case. The oast exterior often remains little changed by conversion, its features giving valued character to the property in its new life. The interior of the kilns and their working parts have fared less well. Preserving them in situ is hard to combine with creating living space in domestic dwellings.

It is, however, still possible to understand how these buildings functioned. Working examples of oast interiors can be seen, for example Beltring Hop Farm, Paddock Wood, Kent and Scotney Castle (National Trust) near Lamberhurst. A scattering of others, some identified and recorded, are known.

Many more oasts and hop kilns remain to be identified on farms and private properties. The remains of early hop kilns are undoubtedly still hidden in many 17th-18th century buildings and further field work may help reveal them.. Special attention in recording them should be given to the upper storey and attics of timber-framed buildings, long converted to other uses, for evidence of roof vents, drying floors or floor holes for hop pressing. This will help us to understand more about the development of these important regional building types which give special character to their local landscape.

Further information

A Perfite platforme of a hoppe garden and nescessarie instructions for the making and maytenance thereof. Reynolde (Reginald) Scot Henrie Denham of Paternoster Row, 1576

The Riches of the Hop Garden Explained. Richard Bradley, Professor of Botany, Cambridge University 1729

The Hop Farmer, E J Lance 1838

The Hop Industry H H Parker 1934

Hops AH Burgess. Pub Leonard Hill 1964 (Brown folder notes and excerpts)

Farnham Buildings and People Nigel Temple. 1963 Herald Press

'Oasthouses in Sussex and Kent Their History and Development' Gwen Jones and John Bell. Phillimore for the Hop Industry Research Survey 1992

Kentish Oasts 16th-20th Century. Their History, Construction and Equipment Robin and Ivan Walton 1997 Egerton

A Pocketful of Hops Bromyard and District Local History Society, First published 1988. Revised 2007.

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