He was introduced to pottery at night classes while training to be a secondary school teacher.
His career path turned after he won a scholarship to study with master potter Bernard Leach in St Ives, Cornwall. During this period, recalled Castle, he absorbed a strong work ethic and became strongly drawn to the Oriental aesthetic.
He wrote of early exposure to pottery: "My relationship with clay became personal and intimate.
"I discovered in myself a strong preference for swelling forms with their hints of fecundity of the organic world; also a liking for pots with texture, tactile qualities and of a scale appropriate for household use.
"I felt strongly that the form of a pot is of major importance, glazes, textured surfaces and decoration should not overwhelm it."
Castle returned from England to a job teaching science at Auckland Teachers' College.
But the restless potter was stirring: he set up a studio in the Waitakere Ranges in 1960 and by 1963 was a full-time potter, supported by his then wife Ruth.
That same year Castle was a force behind the creation of the New Zealand Society of Potters.
In 1966, he won a Queen Elizabeth II Arts Council fellowship, which he used to go to Japan and Hawaii. His trip cemented his love of Japanese pottery.
His science training was evident in his work, which today is held in many major art collections.
He wrote: "In my workshop, by using considerable force I cut, tear, twist and stretch blocks of clay to suggest on a micro-scale some of the aspects of the geomorphology of our restless earth."'
Awards and honours flowed. In 1986, Castle was made a CBE. In 1990, he received a NZ Commemorative Medal, in 2003 an Arts Foundation Icon Award and in 2004 a Distinguished Alumni award from Auckland University. Also that year, he was also made a Distinguished Companion of the NZ Order of Merit. He declined the Government's offer to convert that honour to a knighthood.
Castle twice won book awards. His Making the Molecules Dance won the NZ Post Book Award for illustrative non-fiction. Len Castle: Potter was a Montana Book Award winner.
A tribute to his art and creativity filled the show Mountain to the Sea, which toured New Zealand in 2009-10. It featured a selection of his ceramic works and large-scale photographs taken by Castle over 30 years.
Former Prime Minister Helen Clark wrote that "Len Castle has helped define New Zealanders as different from others through his exploration of the relationships between clay ... and the natural world around us".
"His explorations of geomorphic and geothermal shapes, textures and colours, and his remarkable ability to capture the "wairua" of the land, have brought him and his art work to a previously unrealised and richly deserved international prominence."
A memorial service for Len Castle will be held at 4pm next Friday in the Titirangi Memorial Hall.
Len Castle, DCNZM, CBE
1924-2011