The buildings that enjoy the strongest planning protection against proposals involving demolition or inappropriate alteration are those on the Statutory List of Buildings of Special Architectural or Historic Interest, which is compiled by the Secretary of State for Environment. In Merton Park such listed buildings are :

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• The Church of St. Mary the Virgin

• The Norman archway between the Church and the Vicarage

• The ancient wall of Church House

• Dorset Hall, Kingston Road

• The Almshouse in the corner of Kingston and Mostyn Roads

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Merton Council has also compiled a "Local List" of buildings of architectural or historical interest, to help ensure that any development proposals are sympathetic to the character of the building. There are 145 such buildings in the John Innes (Merton Park) Conservation Area, 50 in the John Innes (Wilton Crescent) Conservation Area, and 26 in the Merton Hall Road Conservation Area and a number in other parts of the John Innes Society's "Area of Benefit".

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In the Conservation Areas there is considerable protection under planning policies and laws to prevent inappropriate developments out of keeping with the character of the area, although inevitably some building modifications have "slipped through the net".

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The John Innes Society, together with other organizations and individuals keen to preserve the special character of the area, is active in commenting on and, where necessary, opposing inappropriate planning developments. Buildings in areas adjoining the Conservation Areas do not have the same degree of formal protection but they do benefit from their proximity, as a major development that may be acceptable elsewhere would not be so in an area immediately adjoining a Conservation Area.

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Most of the holly hedges on the John Innes estate were protected by covenants, and sometimes the retention of a holly hedge has been made a condition of local planning consent for a building alteration. In the Conservation Areas, all holly and other trees (except fruit trees) -with trunk diameters of 3 inches (7.62 cm) or more at a height of 5 feet (1.52 m) - require 6 weeks' notice of felling or lopping to be given to the Council. Trees with preservation orders have special protection.

 

The Council has a programme of replacement of street trees, planting new trees in gaps, and the John Innes Society and other organizations with an interest in the environment have contributed to the planting of new trees in Merton Park. Saplings need regular watering in dry summers, and local residents have been urged to help.