Soil Testing

"Residents who plant without preparing the soil often
end up with persistent lawn problems or landscape
plants that simply do not thrive. Applying fertilizer to the
soil surface after planting will not solve the problem."

"In order to have a healthy, attractive landscape,
take time to prepare the soil before you plant.
Prepare the soil wherever you plan on installing lawn or
landscape plants such as flowers, grasses, shrubs and
trees. Don’t skip this step. There is not an easy way to
go back and fix the soil once plants are installed. If you
are working with a landscape contractor, make sure soil
preparation is part of the installation plan. The first step
is to get a soil test."

Colorado State University Best Practices, Soil Preparation (.pdf)