As many of you know I"m starting my first asparagus patch. The plot is over a newer leach bed and my worries of it getting into the black rich dirt then it getting into the plant itself. The leach bed is probably a foot to a foot in a half under the garden. The reason I choose this are to put my garden is because I had the septic and leach bed put in and this area was already recently excavated. Last year was the first year I had this garden. I could put the patch elsewhere, but it just makes sense to have it here. Any input?