Middleton's disgraced alter ego grew the facial hair while homeless after being barred from his duties as a vicar.
Ashley, whose marriage to Laurel has broken down, was shunned from the village when it was revealed that he had been abusing elderly father Sandy.
Speaking to Inside Soap, the actor revealed: "Everyone keeps saying, 'John, that really suits you!'
"For a while my wife said nothing, but I confronted her about it recently and she said, 'I've watched it grow, and I suppose it's grown on me as well'.
"It's been great for me, though. I begged the Emmerdale bosses to let me keep it, and so far they've said I can!"