Thanks to the soil testing laboratory operated by Texas A&M AgriLife Extension, it’s easy and not very expensive to get a professional soil test in Texas. Simply fill out an online form and mail your sample(s) to the lab (located in College Station). Cost is $12 per sample for Routine Analysis, a basic test for basic fertilizer recommendations. Several add-on tests are available, which increases the price per sample to $19-$89. (Shipping cost is extra.)
According to the Dallas County Master Gardener Association, a division of Texas A&M AgriLife Extension, the Routine Analysis is the one most homeowners should use. It will tell you how much nitrogen, phosphorous, potassium, calcium, magnesium and sulfur your soil contains, and it will advise on any required supplementation. In addition, it will list the sodium content (related to salinity), pH (acidity or alkalinity), and the soil conductivity (also related to salinity).
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