How big are the seedlings? If they are one foot or smaller we put them into a section of the garden we call the tree nursery. They stay well-mulched and pampered until they are big enough (2-4 feet) to move to their permanent location. If you are putting small seedlings out on their own they need some protection. Net or put chicken wire around them staked down with a stick/rod. Mulch them heavily for about 12 inches around. Keep them well-watered the first year. The mulch keeps them moist and protects them from tall grasses. It also makes it easier for you to weedwhack without killing them.