The gravel soils of the southern half of Greenwich Park would naturally have supported a mixture of heathland and acid grassland, which depend on low-nutrient levels and acidic soil conditions.
Acid Grassland, with its fine grasses, wild flowers and other wildlife is of conservation importance in London and nationally. Some relict areas of this habitat remain in Greenwich Park, the largest of which is Croom's Hill. In the spring, look for the spectacular dark-red carpet of the flowers of sheep's sorrel; one of the indicator species of acid grassland.
There are other areas of conservation grassland managed for wildlife conservation in the park. A relaxation of cutting, and keeping some areas uncut each year ensures the survival of a wider range of plants and animals on the site. Of particular interest are the grassy slopes where the soil is less acidic and more nutrient-rich. A good place to visit is the path that runs diagonally up the south west side of One Tree Hill. Here you can see a mixture of tall grasses and wild flowers and the area is just buzzing with bees, butterflies, grasshoppers and other wildlife. There are also a number of plants of fiddle dock, an unusual plant in the London area.