"Damping Off" is an unexpected plant death in the seedling stage caused by soilborne fungi. It is a global problem which occurs in most soils and greenhouses. The disease(s) affect various seeds and seedlings. Cool, wet soils seem to promote development of the disease(s). Pythium, Phytophthora, Rhizoctonia and Alternaria are known to be among the culprits." Damping Off " Disease
Germinating seeds may be attacked by Damping Off which is termed "Pre-emergence Damping Off". When the emerged sprouts are attacked it is termed, "Post-emergence Damping Off". Older plants seem more resistant to attack, possibly because their stems are not as tender, and therefore more capable of preventing bacterial penetration.
Gardeners are seldom aware that their seeds have been attacked; they attribute minimal germination to bad seeds. But when seedlings suddenly fall over at the soil line like a utility pole hit by a truck, and a closer inspection reveals that the plant stem has constricted at the soil line, you can bet that fungus of the "Damping Off" family have attacked.
At this point it is best to discard the infected container to the dumpster or an obscure corner of the garden. If only a few seedlings have been affected, you may try to remove them and the surrounding soil in an attempt to save the remaining seedlings. But it is best to move the container to an obscure location where the disease is less likely to invade adjoining containers.
A natural or commercial Fungicide may be misted over the soil until it is damp. But be reminded that the term "Damping Off" is derived from the dampness that often precedes the disease, and is suspected of contributing to the conditions which promote the disease.
A dusting or misting of seeds or seedlings with Cinnamon Powder, cooled Chamomile Tea, a tincture made with crushed Garlic cloves, or a Hydrogen Peroxide solution may help. So may Thiram or Captan when used according to the package instructions.
A Hydrogen Peroxide solution may be made using the 3% drugstore product, by adding it to a gallon of stirred rain water as follows:
Start with weak dilutions and increase the strength
- 1 to 4 Tablespoons; for watering seedlings and potted plants.
- 3 to 6 Tablespoons; for watering outdoor plants.
- 5 to 8 Tablespoons; for dipping seeds or roots prior to planting or repotting.
- Full strength for cleaning tools and work areas.
until you determine what works for your particular problem
in your particular climate and location without injuring plants.
The first line of defense is to keep seedlings in an atmosphere which has been proven to hinder disease development:
- Try to find seed varieties that are resistant to fungus attack.
- Use new containers, or sterilize your used containers.
- Select a soilless seed-starting mix, which contains no "earth".
- Sterilize your tools and work surfaces.
- Keep the seeds and seedlings moist but not wet.
- Water the containers only from the bottom.
- Never put the containers in water-retaining "saucers".
- Keep the containers in a warm area; 75F. or more.
- Allow and promote air circulation among your seedlings.
- Use minimal misting so as to not wet the soil surface.
- Wash your hands often to prevent disease migration.
