- Peter D. A. Boyd
McNab, William (1780–1848), horticulturist, was born at Knockcavish in the parish of Dailly, Ayrshire, on 12 August 1780, one of twelve children of James McNab, a farmer. He assisted his father on the farm but about 1796, at the age of sixteen, he became a gardening apprentice in the garden of Mr Kennedy of Dunure, at Dalquharran in Carrick. After three years he obtained a situation in the gardens of the earl of Haddington at Tyningham in East Lothian. His character and abilities were quickly recognized and, after only fourteen months, he was recommended to William Aiton for a position at the Royal Botanic Gardens at Kew. He commenced employment there on 12 March 1801, aged twenty, and became foreman in 1803. He gained the approval of George III (who took a special interest in the gardens) not only for his horticultural prowess but also for his willingness to be actively involved with the Kew volunteer infantry, formed, like other volunteer corps at the time, to help repel invasion by the French and subdue civic unrest. The king apparently commented that he had the appearance of a soldier. McNab's correspondence with William Kerr (d. 1814), a friend and former foreman at Kew, shows that the Kew gardens benefited from the actions of English privateers against French ships during this period. The king acquired an important collection of plants from South America, intended for the 'National Garden at Paris', through this means. As foreman at Kew, McNab received a salary of 100 guineas per annum, a house, fuel, and candles, together with access to Kew's excellent botanical library. About 1808, while at Kew, he married Elizabeth (1777/8–1844), third daughter of Joseph and Judith Whiteman of London. They had five sons and four daughters.
In 1810 Daniel Rutherford, regius keeper of the Royal Botanic Garden at Edinburgh, asked Sir Joseph Banks to recommend a proper person to take charge of the Edinburgh garden. It had suffered from a succession of superintendents who only stayed a short time or died in post at a relatively young age. William McNab was recommended by Banks, and William Aiton sent a letter of introduction testifying to McNab's qualities as a gardener, and his possession of 'the sincerity and real worth of an honest man'. Even though the financial rewards were lower at Edinburgh (£50 a year with house, fuel, and candles) than at Kew, McNab had been persuaded that there was great potential for development at the garden and personal advancement. He fulfilled his side of the bargain and praise for his work in Edinburgh came from many quarters, Dr Neill remarking in 1812 on McNab's energy in increasing the collection of plants, despite the discouragement of limited funds. McNab's handwritten records of the acquisition of native and exotic plants between 1810 and 1820 are testimony to his work.
Rutherford and McNab pressed for the Edinburgh garden to be moved from its cramped, 5 acre site on Leith Walk, with its dilapidated glasshouses, to a bigger location. In January 1820, following Rutherford's death, and with a large family to support, McNab addressed an impassioned appeal for more resources, and was endorsed by Sir Joseph Banks and William Aiton of Kew, and later by Robert Graham, appointed regius keeper in succession to Rutherford. His salary was increased to £80 that year, £100 in 1822, and to £150 in 1834. Professor Graham also succeeded in negotiating a new site for the garden at the Rocheid estate at Inverleith. The move to Inverleith was a massive undertaking including the preparation for removal and transfer of mature trees and shrubs (some of them 100 years old) from one site to the other a mile away. MacNab undertook this task between 1820 and 1823, with very few trees and other plants failing to be re-established under his care. As the acknowledged expert in transplanting evergreen trees and shrubs he developed what became known as McNab's transplanting machine. His Hints on the Planting and General Treatment of Hardy Evergreens in the Climate of Scotland was published in 1830. The new garden provided new opportunities, including the construction of glasshouses in which to grow tender exotics that had been favourites since his time at Kew. He became a particular expert in the cultivation of ericaceous plants from southern Africa and published his Treatise on Propagation, Cultivation, and General Treatment of Cape Heaths in 1832. A genus of ericaceous plants was initially named Nabea in his honour (later renamed Macnabia Benth). Although he had a love of exotic plants, he maintained an interest in the native flora of Scotland, producing watercolours of specimens in life before pressing and drying them on herbarium sheets. He became an associate of the Linnean Society of London in 1825.
Plants arrived at the Edinburgh garden from all over the world, though the movement of plants and seeds was not exclusively inwards. The Royal Botanic Garden at Edinburgh also supplied other botanic gardens and individuals around the world with plants or collections. McNab's registers and notebooks recording the 'plants-out' flow of specimens give an insight into the significance that the garden now had as an international centre. In 1826 the tsar of Russia sent him a diamond ring in acknowledgement of his assistance with acquisition of plants for the imperial botanic garden at St Petersburg.
Despite a forbiddingly austere appearance, William McNab was a well-respected and well-loved man, who accompanied Graham and his students on botanical field excursions into the highlands. A testimonial was raised for him in 1844, resulting in the presentation of £400 in a silver snuff box, along with another snuff box made from the root of a bamboo which he had grown to a height of 40 feet during six months under his care at the botanic garden. The Edinburgh professor Thomas Traill observed: 'It is owing to him that our conservatories are now so full of the plants of other countries, and it is owing to him that Scotland has attained such a high name for its scientific horticulture'. He died in post at the Royal Botanic Garden at Edinburgh on 1 December 1848 and was buried at the Calton burying ground beside his wife, who had died four years earlier. His eldest son, James McNab, who worked with him in the Edinburgh garden, succeeded him as curator; his third son, Gilbert McNab (1815–1859), qualified as a medical doctor and undertook botanical investigations in Jamaica; and his eldest daughter, Catherine Mary McNab (1809–1857), published Botany of the Bible (1850–51). Many of his herbarium specimens were left to his eldest son, and subsequently found their way to Ireland through his grandson William Ramsay McNab.
- Gardener's Magazine (1832), 210–11
- Gardeners' Chronicle (1848), 812
- Cottage Gardener, 1 (1849), 165–6
- Botanical Gazette (1849), 52
- Chambers' Journal, 13 (1850), 60–61
- I. B. Balfour, Notes from the Royal Botanic Garden Edinburgh (1908)
- H. R. Fletcher and W. H. Brown, The Royal Botanic Garden, Edinburgh, 1670–1970 (1970), 80–90
- M. Hadfield, R. Harling, and L. Highton, British gardeners: a biographical dictionary (1980), 199
- E. C. Nelson, ‘William Ramsay McNab's herbarium in the National Botanic Gardens, Glasnevin’, Glasna, new ser., 1 (1990), 1–7
- bap. reg. Scot., Dailly
- census returns, 1841
- Royal Botanic Garden, Edinburgh, diaries
- J. Somerville, lithograph, repro. in Gardeners' Chronicle, 50 (9 Dec 1848)
- portrait, RBG Kew
- portraits, Carnegie Mellon University, Pittsburgh, Hunt Library
Wealth at Death
£783 14s. 1d.