Identifying the Baseline Areas

Dear All, I want to double check on how to allocate the Baseline areas for my project. My proposed project has 100 sq.m of trees, 300 sq.m of shrubs, and only 5 sq.m of turf grass. Shall I allocate the same areas for my baseline scenario (100-300-5), or do I have to lookup the typical landscaping schemes in my country and adjust accordingly? I believe that the typical project in my country includes a larger area for turf grass (~20% of landscaped area). Am I obliged or do I have the option of changing the baseline areas (increasing the turf grass percentage while decreasing the trees / shrub percentages)? Thanks!