You won't necessarily have a problem with damping-off in potting soil. The fungal organism would need to be present first; if the soil was sterile, chances are it won't be a problem. Remove the plastic wrap when the seeds have sprouted. You don't want too much moisture on the foliage fungal may occur. One sign of damping-off is when the plant falls over at the soil line. If you see this, you can remove the section of plants affected and save the rest of the seedlings.
Do not turn over the soil in your garden too early. If you cultivate wet, soggy soil, the soil will become compacted, especially if you have clay soil. An easy way to determine if the soil is too wet is to pick up a handful of soil and squeeze it. If it forms a solid ball, it is too wet, but if it forms a loose ball that falls apart, it is ready to till. If soil sticks to your shoes or shovel, it is too wet.
