A brilliant man with a deep understanding of agriculture and nature, he is much respected by those who work under him.
As war progresses, he becomes an even greater taskmaster, with the focus on feeding the troops and the Home Front becoming more and more of a priority.
Like John, he has family fighting in the war – his two sons Tobias and Ernest. The thought of losing them has led Mr Leathley to become obsessed with his new war-time responsibilities – to turn the once ornamental and decorative gardens of Harewood into a hive of food production and cultivation.
Seeds of Hope continues in the Walled Garden until Sunday 4 November.
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