Hailing from a farming family in Aberdeen, his early training was in the Aberdeen Parks Department and at Dunecht Estate.
Known as a man of stern commitment, he was hailed as being ahead of his time. In the late 1950s he argued that plants should not just be collected for collection’s sake and that it was the responsibility of botanic gardens to make themselves available as living and usable education facilities for all.
He became the very first recipient of the Royal Botanic Garden Edinburgh medal in 2001 as a reward for decades of work, research and tuition.
His association with the Botanics dates back to 1932, when he arrived as a student gardener. Within three years he was heavily involved and travelled round the world collecting samples, which had never before been brought to Scotland.
During the Second World War he served with the Royal Artillery and Intelligence Corps, his fluency in German resulting in him being seconded to Force 134, which led the immediate post-war Allied occupation of Norway.
Upon returning to civilian life he was appointed curator of RBGE in 1950, a post he held for 21 years. During that time he enhanced its international reputation as a centre of excellence and helped develop courses at numerous universities.
He developed two specialisms – the integration of trees into urban environments and plant propagation – and became a renowned authority in both spheres.
In his last decade at the RBGE he persuaded the Department of the Environment to demolish the old public glasshouses and embark on the design and construction of the unique, externally suspended modern range still in place today.
He was also honoured at a civic reception by the city council for his arboricultural advice and contribution to the city’s treescape in 2001, which Councillor Steven Cardownie referred to as Edinburgh’s green inheritance.
The Royal Horticultural Society awarded him a Victoria Medal of Honour and at his 100th birthday party a specially commissioned Gold Medal Award for Achievement was presented to him by the Botanics.
Dr Kemp was also awarded an MBE for his work at the garden, while other achievements include turning a piece of Dundee wasteground into a thriving educational resource.
He moved to Dundee following his retirement from the RBGE in 1970 and became the first curator of a new botanic garden for Dundee University in 1971 where he remained until 1980.
In 1954, he married his wife Helen. The couple had one son, Alan. He is also survived by three grandsons.