The Blakes were the third owners of Danesbury, and it was William John Blake, son of William Blake, who in 1859 directed their Head Gardener, Anthony Parsons, to build a Fernery. It was completed in 1860 and later gained wide acclaim.
The Blakes moved out of Danesbury in 1902 and after renting it out, eventually sold the house in 1919 to the Dewar family. The Dewars were destined to be the last family to live there.
The Dewars moved out in 1937 and in 1939 the House became a TB Hospital. Danesbury Park itself was requisitioned by the Army in 1943 and operated as a Command Bakery run by the Royal Army Service Corps.
In 1944 the Dewars sold the estate to the Barnet (Hospital) Management Group and the House became home for long stay hospital patients.