Work is to start on Leeman Road Millennium Green as part of the York Central project.
Under the plans, work will begin next week on clearing away brambles and shrubs around the footpath entrance to the green at Garnet Terrace.
Several trees next to the footpath will be removed. The viewing platform will be refurbished, about 300 metres of footpath will be improved with stone and timber edging replaced.
Three new benches will be installed at the southern end of the site, the Millennium Green signs moved and a new fence put up along the boundary between the green and the end of Garfield Terrace.
The footpath will be closed and fenced off during the work. Millennium Green will remain open – but access over Holgate Beck to Garnett Terrace at the southern end of the park will sometimes be closed.
A City of York Council spokesperson said trees will only be removed if it is essential. The Millennium Oak and the mosaic will be protected while work takes place.
An area of trees will also be removed from land next to Bishopfields Drive, to allow the York Central infrastructure works to take place later in the project.
The work will be carried out by builders John Sisk and Son on behalf of the council and letters are being delivered to neighbours to inform them of the plans.
Council leader Keith Aspden said: “The council will continue to working closely with John Sisk and Son to limit any disruption to neighbouring residents and businesses, and to keep them informed of any planned works.
“As ever, we thank all local residents and businesses for their patience.”
More than 300 mature trees are set to be planted during later phases of the work.
In 2018, the Millennium Green Trust agreed to allow some land to be used during construction of the York Central scheme.