Trevor first ran for office in 1985 and then in the European elections of 1989, won 8.3% of the Dublin vote. Two years later, in June 1991, he was elected to Fingal County Council and a year later, in November 1992, to Dáil Éireann. He topped the poll in 2002 with nearly 17% of first preference votes in the market gardening constituency of Dublin North and was comfortably re-elected in May 2007, after which he was appointed Minister of State for Food and Horticulture.
Trevor is co-founder and was, until his appointment to Government, a board member of Sonairte, the Irish National Ecology Centre, near Julianstown, County Meath which is an Agricultural Training and Visitor centre with a 2.2 acre walled organic garden. He is also a member of Amnesty International, the Dublin Food Co-op, the Irish Organic Farmers’ and Growers’ Association, Organic Trust and a former member of Macra na Feirme.
A former teacher and fluent Irish speaker, he relaxes by reading, walking and playing music. His favourite form of relaxation is tending to his prolific organic garden at home in Balbriggan, North County Dublin, an area known by many as Fingal.