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Leading women

Cracking the codes of gardens: The life of Mavis Batey


Ahead of our Open Gardens events in Gordon Square on 9-10 June, we explore the remarkable life of Leading Woman Mavis Batey: Bletchley Park code-breaker and garden historian.

Mavis Batey

'Hello, we're breaking machines. Have you got a pencil? Here, have a go.' With these words, 19-year-old UCL student Mavis Lever was introduced to the Enigma research team at Bletchley Park by Greek scholar and veteran cryptographer Dilly Knox. Midway through her French and German degree as war broke out in 1939, Mavis’ language skills led her to become one of the top code-breakers of the Second World War, playing a leading role in breaking both the Italian and Abwehr Enigma machines. After the war, however, her pattern recognition abilities led her to a quite different career: decoding the language of historic gardens, in the process becoming the driving force behind English Heritage’s national register of parks and gardens. 

‘Give me a lever and a rock and I will move the universe.’

After impressing the Government Code and Cypher School by realising that a mysterious Morse Code place name S-T-G-O-C-H was not St Goch but Santiago, Chile, Mavis was sent to Bletchley Park to work with Dilly and his largely female team on breaking the Enigma ciphers. In March 1941, she decoded an Italian Enigma message which read, ‘Today’s the day minus three’ – working round the clock for three days, the team unravelled a series of messages which allowed the Royal Navy to ambush an Italian attack at the Battle of Matapan. Later that year, Mavis broke into the German Abwehr Enigma, previously deemed impossible to break, enabling Allied forces to stage the D-Day landings in 1944. Dilly gave enormous credit to Mavis and fellow coder Margaret Rock for this, remarking ‘Give me a lever and a rock and I will move the universe.’ 

Mavis fell in love with mathematician Keith Batey after the two worked together on a particularly difficult cipher during a late-night shift. Marrying in 1942, the couple remained at Bletchley until the end of the war.

The arboretum at Nuneham Courtenay

‘Someone had tried to say something there’: The language of gardens

Spending several years in Canada with their young family, the Bateys returned to England in 1955, settling in Farnham, Surrey. It was here that Mavis first became interested in landscape history, inspired by historian W. G. Hoskins’ study of the evolution of the English landscape. This intensified when the Bateys moved to Oxford to live in the grounds of Nuneham Courtenay, a sprawling 18th-century park designed by Capability Brown. Mavis became fascinated by its William Mason garden, sensing patterns in its design in the same way that she had previously analysed codes. ‘I knew at once it wasn't just an ordinary derelict garden: someone had tried to say something there,' she recalled in a 2008 interview.

Mavis spent the next few years researching Nuneham Courtenay, publishing her findings in Oxoniensa in 1968. She went on to produce several books on historical gardens across the south of England, as well as writing about literary gardens in the works of Lewis Caroll, Austen and Pope.

From code-breaking to campaigning

As Mavis’ knowledge of gardens developed, so did her realisation that none of these historic spaces were afforded any official protection. ‘It seemed to me that the moment I'd got interested in these lovely landscape parks, they came under threat. The Ministry of Transport actually said that putting a road through Highclere Park would give the motorist something good to look at as they drove through!' she recalled in 2008.

Mavis became the Secretary of the Garden History Society in 1971, and began campaigning to preserve historic landscapes. Her efforts led to the 1974 Town and Country Amenities Act, the first legislation to recognise the concept of historic gardens alongside listed buildings – after which she turned her attention to the creation of a national register. Organising a pilot study – and singlehandedly surveying the gardens of Oxfordshire after government funding failed to materialise – Mavis’ findings grew into English Heritage’s first Register of Parks and Gardens of Special Historic Interest.

For many years bound by the Official Secrets Act, in later life her achievements were finally made public. In 2004, she brought together the two strands of her career by creating an American Garden Trail at Bletchley Park, filled with flowers and trees from each of the United States. Dying in 2013 at the age of 92, her codebreaking work was celebrated around the world.

From breaking Enigma ciphers to preserving historic gardens, Mavis Batey’s work has had a considerable impact. As she later recalled, ‘You should make your voice known. You never know how things are going to turn out.'

Dr Elizabeth Dearnley teaches within the School of European Languages, Culture and Society at UCL and is Communications & Engagement Assistant for the University of London’s Leading Women campaign. You can find her on Twitter, @eliza_dearnley

Join us for our free Open Garden Squares event, on 9 and 10 June!