Barrett has almost 40 years of turf production experience.
Inturf joint managing director Alex Edwards said: "Sales have been increasing exponentially for some time now. The fact is that, with increased production, we could sell even more so we’re excited by the contribution that Guy can make."
Barrett said: "I’ve known and respected Inturf all my working life and now relish the opportunity of using my experience to help them realise their vision for the business."
Inturf was established in 1985 and grows turf for golf courses, landscapes and gardens.
Joint managing director Stephen Edwards added: "We are hugely optimistic about the turfgrass industry. In particular we know that there are opportunities for Inturf waiting to be exploited and Guy’s appointment will help us to just that."