Q: Any suggestions what we might plant over septic field to add some interest to the blank area? It gets filtered sun.
A: Trees and shrubs are risky to plant over or near a drain field. Their roots penetrate more deeply than grasses and flowers. Once their roots find the constant source of moisture and nutrients that a septic pipe affords, the roots will invade the pipe.
The best place to plant a tree is near the end of a line, where it is drier and less attractive to root growth. If you insist on planting a shrub over the drain field, the ones that have fibrous roots, such as holly, boxwood, azalea and rhododendron would not be likely to invade pipes. Even a small tree, such as dogwood or dwarf Japanese maple could be considered. Here are other choices to think about:
NOT RECOMMENDED NEAR DRAIN FIELDS
BETTER CHOICES TO PLANT NEAR DRAIN FIELDS
ALL FLOWERS WOULD BE FINE TO PLANT.