Richard Haddock wants to add a garden centre, three polytunnels, a coffee shop and toilets to his farm shop on a semi-rural site near Brixham, Devon.
Torbay Council agreed to the expansion of Churston Traditional Farm Shop even though the plans breached rules concerning building on areas of landscape importance.
Haddock said the planning delay had scuppered plans to open this year. Building was now due to start late this year for a spring opening.
Objectors argued that the plans represented "over-intensification", sent the "wrong message to developers" and went against policies in the local plan.
They said there were five garden centres within 6.5km already. However, planners said that sales could be restricted to plants and exclude items such as machinery, sheds and conservatories.
Councillor Peter Addis said: "There is a park and ride, a go-kart track and Cayman Golf on that road, so it is hardly the heart of the countryside."
Planning service manager Ivan Woodcock said: "Approval was on the basis of rural diversification, which outweighed our normal policy of going with the local plan."