The five-centre business, which has its head office in Hertfordshire, has this month been awarded a three-year contract with the London Borough of Enfield. Earlier this summer, the firm won five-year contracts with the London boroughs of Southwark and Ealing.
Director Andy Toms said: "These are significant contracts for us and we're immensely proud to be given the responsibility to care for the trees in these boroughs.
"We're very keen to develop other areas of the business too and the long-term contracts provide us with the stability to do that."
Gristwood & Toms will be exhibiting at IoG Saltex, held in Windsor next month, where it will be launching two new services and revealing a new brand image.
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