2008 Durability Guaranteed Pulhamite rockwork – Its conservation and repair Contents Introduction 3 What is Pulhamite? 3 Rock gardening 3 James Pulham & Son 4 Pulhamite rockwork 7 The ‘Pulhamite system’ 8 Pulham’s terracotta 8 Planting 9 Pulham sites 10 Clients 10 Associations with landscape designers, gardeners and architects 11 Deterioration and damage 11 Defects in the render coats 11 Defects in the core or backing 13 Previous repairs 13 Site assessment 14 Conservation-based research and analysis 15 Conservation, restoration and maintenance 18 Mortar analysis 18 Mortars for repair 18 Repair trials 18 Render repairs 18 Structural repairs 20 Cleaning 20 Vegetation control and replanting 21 Maintenance 21 Appendix A: A gazetteer of Pulham sites 22 Gardens and parks 22 Buildings 29 Terracotta work 29 Ferneries, rocky banks, alpineries and conservatories 30 Dropping wells and pools 32 Rocky recesses, grottoes and caves 32 Miscellaneous 32 Sites listed in Pulham catalogues from the 1920s and 1930s 33 Possible sites 33 Appendix B: Sources of advice and information 34 Glossary 34 Bibliography 36 An early 20th-century postcard of the Pulham rockwork at Battersea Park and a Websites 39 contemporary view. (© EH PC06588; DP016938) FRONT COVER: James Pulham & Son catalogue c1920s. (© RHS, Lindley Library) Introduction Rock Gardening In the 19th and early 20th centuries, the From as early as the 17th century British It was not until the early 19th century that the Pulham family became renowned for creating gardens included grottoes as ornamental concepts of ornamental design and scientific a wide range of artificial landscapes, from features. In the 18th century rock displays interest were fused in the distinct genre of small, exquisitely planted rockeries and were often added for their scientific interest, rock gardening. A growing passion for ferneries to grottoes and temples, from as at the Chelsea Physic Garden in London. gardening was creating an expanding market elaborate water gardens, complete with Terms such as ‘rock’,‘artificial rock’ and in plants, seeds and tools, gardening services chasms and cascades, to massive coastal cliffs. ‘rockwork’ were in use in this context by the and design. Newly-discovered plants from the These fashionable bespoke landscapes brought 1770s and usually referred to a garden world’s mountainous areas were being together many of the hallmarks of 19th- created as a specialised habitat for alpine and imported and cultivated. century garden design, including the interplay rock plants. In 1767, John Blackburne of of landscaping, botany and geology, engineering Orford, Lancashire, wrote ‘I am going to make and architecture, and innovation in materials a piece of rockwork for plants yet grow in and techniques. Collectively, they gave tangible rocks, viz: sedum, stonecrop, licopodiums, form to the Victorian passions for travel, for lichen, mosses etc’ (Wright 1925).The Chelsea plant collecting and for gardening. Physic Garden rockwork was made of 40 tons of stone, including flints, chalk and lava. It The Pulhams prided themselves on the survives, although significantly changed in strength and workmanship of their products – appearance. Illustrations of other early rock ‘Durability Guaranteed’ – and many gardens, gardens are scarce. Early botanists and ferneries and other features have survived, gardeners were creating rock gardens to forming a living record of their work.While imitate nature, even if their perspective on some features have been lost (more to what was ‘natural’ was to be superseded by vandalism and redevelopment than to later designers. deterioration), most of the structures are surprisingly robust. Many are, however, in urgent need of repair or restoration. The Pulhams used both artificial and natural rocks, and also made garden architectural Fig 2 Joseph Paxton’s vast 1840s rock garden at ornaments. Common to all of their work was Chatsworth. (© John Watkins) a proprietary cement with a striking resemblance, in colour and durability, to The collection of rock plants had, by the 1830s, natural stone, and which came to be known become a major branch of horticulture, with as Pulhamite. rock gardens the ideal place for their display. Initially only ferns were grown on the rocks This Technical Advice Note tells the story of themselves, with adjacent sheltered beds used James Pulham & Son and the building and for alpine plants. From the 1860s alpines were planting of their rockeries and other features. also cultivated in pockets on the rocks. It reviews common defects affecting this Unheated alpine houses and indoor ferneries fascinating but ageing rockwork, and provides were designed to display specimens needing guidance on assessing its condition and cooler conditions. Although the design and undertaking appropriate repairs.This advice structure of rock gardens was variable, draws on the conservation expertise of eminent landscape designers like Humphry consultants, both garden historians and Repton (1752–1818) and John Claudius building conservators, including those from Loudon (1783–1843) promoted the idea of local authorities and from English Heritage. picturesque, rugged and naturalistic formations Through grant aid, the Heritage Lottery Fund on banks away from the main house, and has helped to stimulate research and repair. Fig 1 The Chelsea Physic Garden rockery was made from more formal displays of alpine and rock A gazetteer of sites and places with volcanic stone from Mt Heccia in Iceland (brought back by plants in flower gardens. Loudon’s An Joseph Banks in 1772) and rubble from the Tower of Pulhamite rockwork is included at the end of London. It is probably the first rockery in Europe built for Encyclopaedia of Gardening (1822) includes a this publication. the purpose of displaying plants. (© EH/Ben Simpkins) crescent-shaped design for rockwork. What is Pulhamite? The term ‘Pulhamite’ is associated with at least two different materials considerably over time, it consisted of an eminently hydraulic lime or manufactured at different times by the Pulham family and firms natural cement binder, gauged with sand and other aggregates. associated with them. The other use of the term ‘Pulhamite’ is in reference to a One is a mortar for use as a render, described by the Pulhams as a stone-coloured terracotta material, rather like Coade Stone, which the ‘cement’, developed in the 1820s by the Lockwood and Pulham firms. Pulhams developed in the 1840s and used until the 1880s for pre-cast This was used most famously by the Pulhams in their artificial garden or architectural ornamentation.The term was applied in this rockwork from the late 1830s until the late 1870s. It was referred to latter sense well into the 20th century. variously as Lockwood’s Portland Stone Cement, Pulham’s Stone Cement and, later, Pulhamite.The render was applied to a masonry While this Technical Advice Note examines the historical background core or backing structure to produce texture and colour variations in of both materials, it concentrates on the conservation of rockwork imitation of natural rock.While its exact composition probably varied features, as their treatment has been largely neglected. 3 In the 1830s, many rock gardens used imported natural rock. Syon House, Hounslow, for example, had a rockery of granite.The famous rockwork at Hoole House, Cheshire, designed in geological imitation of the Savoy Alps, employed rock imported from Wales. Professional rock builders were commissioned to design the rockwork. An 1831 article titled ‘An essay on rockwork in garden scenery’ in Gardener’s Magazine (S T P 1831) explained: The use of rockwork in gardens may either be as a distinct feature; as a situation for cultivating plants; [or] as a screen for concealing objects . few objects produce a more striking effect than immense masses of stones, piled together in such a way as at once to give a particular character of rocky mass, and to form a proper nidus for valuable plants. The grand difficulty in rockwork is to Newman finished the cement with a coat of Fig 3 A path winding through the Backhouse rockery at form and maintain a particular character Aysgarth in Yorkshire. (© Andrew Wimble) or style in the disposition of the masses; oil paint to give the appearance of ‘veined or and the only way to conquer this stratified granite’. although today’s labour and transportation difficulty is to observe the manner in costs, along with environmental considerations, which masses of rock are disposed in The Pulhams anticipated a change in aesthetics make massive-scale rock gardens unviable. nature, or rather in such natural scenes in the 1880s towards rockwork that looked as are admired by men of taste, and geologically authentic.They created picturesque James Pulham & Son especially painters. And here the study effects by using a single variety of stone laid in of geology will assist both the painter horizontal strata, with ledges and pockets for The Pulham family business was set up by and gardener. plants.They also coloured their artificial rockwork James Pulham I (1793–1838; C Hitching, pers to imitate different rock types, including the comm), and the firm was developed in turn by Some designers, such as Mr Gray (who indigenous rock of an area; constructed larger the eldest sons, all called James, in three worked on the Colosseum grotto in Regent’s features that would otherwise require inordinate successive generations. Park, London, and the rockery at Clumber volumes of imported stone; and created realistic- Park,Worksop, Nottinghamshire), preferred to looking stratifications. Perhaps aware that their James Pulham I commenced his career with the work with natural rock.The York nursery, artifice could not always be disguised, the Lockwoods, a family of builders in Woodbridge, Messrs James Backhouse & Son, who created Pulhams often made their smaller commissions Suffolk, manufacturing cements. Around 1806 rock gardens across the UK between 1864 more fanciful than nature, or created simple James Pulham I created the architectural and the 1920s, had invented a rock-lifting structures intended solely for the display of plants.