A meeting on Tuesday was told that ecological concerns over the possibility of slurry leaking into the River Clun from Tadymoor Farm, in Hopesay, near Craven Arms, had been dealt with.
A dirty water lagoon will be covered over and trees planted, Shropshire Council's southern planning committee heard.
The committee decided by a unanimous eight to nil vote to support farmer William Grant's diversification plan.
Members had heard that the plan had been implemented without the relevant permission.
Council enforcement officers said they had permitted development rights for a freestanding agricultural building for storing fodder, straw and machinery. An application was submitted to regularise the situation.
Councillor Richard Marshall said: "It is important for us to support our farmers. I absolutely agree that it blends in well."
Councillor Robert Tindall, a land agent by profession, said he was "very happy to propose acceptance" of the part retrospective plan.
Meanwhile, Councillor Nigel Hartin said there had been concern over the retrospective nature of the application but the building was smaller.
"I'm happy to second it," he said.