Before you dig a garden, it's important to figure out what type of soil you have and then select plants (and amend your soil) accordingly.

Besides taking a sample to a lab for a soil test ... “Technically speaking, you can’t transform your garden soil into loam by adding sand or clay, because that results in a muddy mess ...

Soil samples should represent only one type of planting ... organic matter content, percentages of sand/silt/clay, textural class, and gravel content test would be an additional $90.