A disease of germinating and newly emerged seedlings caused by many species of fungi, including Pythium, Rhizoctonia and Phytophthora. Symptoms include decay of seeds prior to germination, rot of seedlings before emergence from the root medium and development of stem rot at the soil line after emergence. Causes include bad handling, poor quality or unhealthy soil, over crowding, synthetic fertilizers and poor drainage.
Small plants fall over as if burned at the ground line. This is a common problem when so-called sterile potting soils are used with synthetic fertilizers and toxic pesticides. Damping off can be can be avoided by using organic amendments to stimulate biological activity in the soil. Another preventative is to use colloidal phosphate or horticultural cornmeal on the surface of planting media. Keep soil moist, but not waterlogged. Provide good air movement and always use living organic material such as earthworm castings or compost instead of peat moss in the seed beds. Wait until soil is warm enough for the specific plant before seeding. Spraying and drenching with aerated compost teas works as a preventative and curative.
Damping off disease in lavender and begonias.