Southerham Farm is a 131-hectare (320-acre) nature reserve on the eastern outskirts of Lewes in East Sussex. It is managed by the Sussex Wildlife Trust.

The thin and infertile soils on this chalk site result in a floristically very rich grassland. Plants which flower in the summer include horseshoe vetch, kidney vetch, mouse-ear hawkweed, field scabious, dropwort and salad burnet.

50°51′54″N 0°01′34″E / 50.865°N 0.026°E / 50.865; 0.026