Question
Will it hurt a tree to build up the ground about a foot high and ten feet around the base of the tree in order to plant flowers?  If so, is there a "minimum" amount of this a tree can stand?

Answer
Diane,

You never want to build up the soil around the base of a tree.  This is an important area for gas exchange for the tree and is probably the number one reason for tree death in the landscape.  

You can build up if you leave about a 5 foot diameter circle around the trunk of the tree and then only about 3" high for the built up area.  

You can always plant flowers in the area around a tree with a 2"-3" layer of mulch without buiding up the area and have good success.  

Good gardening

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