English Garden, painted in 1965, is on display before it goes under the hammer with estimate of £2.5m-£3.5m

David Hockney’s first English landscape, depicting a perfectly manicured Oxfordshire garden, is on show for the first time in three decades before being auctioned.

Sotheby’s said the 1965 painting, English Garden, which was completed in Boulder, Colorado, was pivotal for Hockney as well as holding an important place in wider art history.

“It is a seminal painting,” said the Sotheby’s co-head of contemporary art in London, Tom Edisson. “It really lays the foundations for everything that was to come after.”

The painting has gone on display at the auction house’s central London galleries before its sale on 4 March, with an estimate of £2.5m-£3.5m.