Marigold seeds are among the first I grew as a child and the tip I remember was this: Don't plant them too deep! Start the seeds indoors in a pot with good drainage using potting soil. Just barely sift a bit of soil on top of the seeds then press them firmly into the soil with the heel of your hand. Give them sunlight and keep the soil moist not wet. Transplant the seedlings when they have their second set of leaves. Do not put them outdoors until all danger of frost is past. Keep growing, Marianne Binetti