Douglas Mackay Henderson CBE FRSE FLS (30 August 1927 – 10 November 2007) was a Scottish botanist, the 12th Regius Keeper of the Royal Botanic Garden Edinburgh from 1970 to 1987.
He was born in Blairgowrie on 30 August 1927, the second son of Captain Frank Morrison Henderson of the Ben Line, and his wife, Adine Cornfoot Mackay.
his influential tutors included William Wright Smith, Malcolm Wilson and Harold Fletcher and he graduated with first class honours in 1948.
After overseeing expansion of the herbarium and the library, he took sabbatical leave, sponsored by the US Atomic Authority, to work on pollen structure in Solna, Stockholm.
There his work introduced him to poppies in the genus Meconopsis and led to a seminal paper on the pollen of the constituent members.
On his retirement in 1987 he accepted the post of Administrator at Inverewe Garden, Wester Ross for the National Trust for Scotland.