In our back yard, we have a spruce tree that grass doesnot grow under so we are thinking about building a raised bed under the tree and planting some flowers or something. I asked one friend of mine and she says not to do it as putting a bed over the spruce roots and up the trunk a bit will kill the spruce tree. Is this true. I don't want to kill off the tree, I just want to make a nice flower bed under it. I am also not sure what kind of plants will do well under those conditions. Must like shade and I am assuming higher acidity of the soil because of the needles. Can anyone help?