Scott and I aren’t experts at seedling fatality diagnostics, but
we’re pretty sure that for the last two years in a row at least
one of our tomato seedlings has succumbed to ‘damping off.’
Damping off or seedling rot is caused by fungi that live in the
soil. When you keep the soil continuously damp, give it some
high humidity and maybe some cloudy days it sets that fungi in
action and ready to destroy your fragile little seedling stems.
How Do You Notice Damping Off? We first notice it when the base
of the 1″ stems get thin and white, the next day they fall over
and die. Sometimes the damping off will affect your seedlings
before they even sprout. How can You Prevent it? You can prevent
Damping Off by sterilizing everything before you plant your
seeds. If you make your own seed soil mix you can sterlize your
seed soil in the oven with this tutorial. Make sure to wash your
planting flats thoroughly too. When seedlings are crowded
together that also will activate the fungi, so try to only plant
one seed per pla