I think people have used sand before to keep the top of the soil drier, thus trying to prevent damp off. But I think it would hamper germination.

I am not sure about the gravel idea though. I have always monitored my watering carefully ad used sterile equipment and soil and I have never had a dampening off problem.

I will be interested to see if any others have used the gravel.

Keriann~

I do...for larger seeds, I'll sow and cover with the sowing medium, then top pots with fine aquarium gravel. If using it with very tiny seeds, I'll prepare the pot with the gravel complete, sprinkle the seeds on that and wash down in with a spray of water to make soil contact. It works especially well for those pots of perennial, tree, shrub seeds that are going outside for the temperature fluctuations, the gravel will keep seeds from being dislodged in a gully washer rain and prevent a crust from forming if there should be a drying wind. Discourages algae and mosses for those pots that are going to be a while in germinating.

But I'll use chick grit or crushed pumice as a topping just as often. Will help to control damp-off as it doesn't hold as much moisture at the surface. It also helps to control the growth of those unwanted green things (algae, lichen, moss) under lights. Light layer for those things that have small seeds and those that require at least some light for germination, heavier topping for the rest.

I plant my tomato and pepper seeds in small holes about 3/8 inch deep I make in the seed starting mix with the eraser end of a pencil. After dropping a seed in the hole I backfill it with pure vermiculite soaked in the potassium nitrate solution I presoak my seeds in. It doesn't take much, maybe a quarter teaspoon per a hole. The vermiculite in completely sterile, and very easy for the seedling to push through. Even if mold forms on the surface of the potting mix it doesn't effect the seedling because it is pushing its way through pure vermiculite.