Hi there, I have bought some young pampas grass and would like to plant it, but my yard is hardpan. The soil is so hard that after the first 4" I have to get the pick out. (It is nothing for me to spend a few hours digging a hole for a tree or climbing rose). So the question is: if I want my pampas grass to do well and grow to it's potential size of about 10ft (I understand), how big should I dig the hole, width and diameter to ensure the roots will be able to support the pampas grass' huge size? Thanks in advance Steph P.S. Am I right to believe that hardpan soil is very restrictive and basically unpermeable to tender roots and therefore when I dig a hole it's like providing a pot for whatever I plant in it.