Found this on a web site below. Hope it helps you
The pine tree has a unique beauty and appeal once fully grown. Taking proper care of seedlings goes a long way in ensuring the tree reaches full maturity. These care instructions will help you promote healthy growth of your pines.
Pine tree seedlings are fragile so proper handling is crucial in ensuring their survival up to the time they are planted and beyond.
It is best to retain them in the moist bundles they are found in when obtained at the nursery. They can last up to 3 weeks this way.
Keep your seedlings cool and moist until you are ready to plant them. Avoid placing them in sunny or windy areas as this will cause drying out of roots. Do not let them freeze. Keep them in a shaded spot.
Keep the bundles loosely to encourage air circulation and water them well every other day. Bundles should be restacked after watering. Raise one end slightly to facilitate proper drainage.
It is best to plant your seedlings after a period of good rainfall when soil will be sufficiently moist. This is vital in encouraging the healthy development of conifer trees.
Look out for excessive sun, wind or freezing conditions as these constitute the greatest danger to pine tree seedlings.
Read more: http://www.doityourself.com/stry/caring-for-a-pine-tree-seedling#ixzz17jqItIA9