Backfilling with 18-24" of soil would surely damage your trees. Why don't
you just try planting things that will thrive in the exisiting soil under
the trees. I've got a little island of redwoods where ferns, trillium,
vanilla leaf, Soloman's seal, ginger, hosta, violas, lamium, epimedium,
Vancouveria, huckleberry, vine maple and other shade tolerant plants are
growing. It's my own little forest.


(Chris) wrote:

I was looking back through this group to see if I could find an answer
to my questions but I could not. So here goes. I bought a new house
last year that was build where an old shopping center was. I am in
the back corner of the subdivision and the builder left all the old
redwood trees that lines the old shopping center. I love them, but
want to clean up the look of my backyard. The trees range from 6" -
18" in diameter and 20 - 60+' tall and run the entire length of my
back and side fence, one about every 4-8'. What I would like to do is
build a 18-24" retaining wall about 2' infront of them and backfill
that with soil so I could plant some flowers and other shade loving
plants. I have always heard that backfilling soil like this against
the tree trunk can kill the trees. Is this true? If so, could I
build some sort of box around the trunk and fill with gravel to keep
the soil away and still build my raised bed?