Damping Off

Damping off is a fungus that attacks young seedlings, normally killing them, but can be controlled thru good sanitation and cultural practice. If the fungus kills (rots) the seedlings before they sprout, it is called preemergence. If it kills them after they sprout, it is called postemergence. Thoroughly wash your plastic containers with soap and water, and rinse in about a 10% bleach solution before using them in spring. And whatever you do, don’t over water or over fertilize the seedlings - a common mistake among beginners. Wet growing media and high nitrogen encourage the damping off fungus. Overcrowding can also play a role, so allow plenty of air space between the seedlings.

The usual sign of a young plant that has been attacked by the fungus is a very thin (sunken) stem right at the soil line. The young plant will usually wilt, fall over and die. If this happens, remove the plant as soon as possible, and assess weather or not you have been over watering.

We have found that if you spread a thin layer of very fine milled sphagnum peat moss – not regular peat moss- over the top of your seedling trays, it can help prevent the damping off problem.