[Arid_gardener] Question from Home-Hort WWW page

[Chris Trask]

>
> I plan to start a new garden in Sun City. I will add
> compost and sand to the soil. How much Gypsum would you
> recomend? I don't want to add too much. Thanks!
>

    It would be best if you didn't use any gypsum at all.  In time, the
gypsum dissolves and you are right back where you started with the clay
problem.  The long-term solution, which I learned while working at the
Boyce-Thompson Arboretum, is to remove the clay and then mix the remaining
usable soil with sand and compost (or mulch).

    Many years ago I used the prescribed gypsum method, only to discover
that the high amount of clay in desert soils is pervasive.  I also tried
dilluting it by just adding sand and mulch, but with little success.  It
wasn't until I learned to remove the large lumps of clay and then backfill
with the soil/sand/compost mixture that I made any real progress.  Now I
rarely lose any nursery stock except to excessive summer heat.


Chris Trask
Outings Leader, Sierra Club (1981-1991)
Palo Verde Group Outings Chair, Sierra Club (1985-1988)
Grand Canyon Chapter Outings Chair, Sierra Club (1988-1991)
Member, Arizona Native Plant Society
Member, Arizona Governor's Advisory Council on Invasive Species (2005-2006)
Member, Arizona Riparian Council
Member, Central Arizona Weed Management Area

     We cannot command nature except by obeying her.

                                 - Sir Francis Bacon