February 4, 2012

1 - Soil test results can be used to make recommendations for organic gardens, just tell that you want organic recommendations.

Yard and Garden
February 4, 2012

Please advise how i may have my garden soil tested in order to make amend using only organic fertilizer and materials.

David L.

When you send your soil sample to a lab for analysis, there should be a place for you to identify the manner in which this soil is used - farm, lawn, fruit trees, vegetable garden, or flower garden. When you identify the use, specify that this will be an organic garden. If there is only a check box beside the use, there will be some place on the sample submission form to specify that you want recommendations for organic gardening. Most soil testing laboratories will give recommendations based on your request.
As a retired extension faculty member from NMSU, I tend to refer people to the NMSU SWAT lab (The Soil, Water, and Agricultural Testing Laboratory). The laboratory's physical location is PGEL Building, Westside Entrance, on the NMSU campus. The mailing address is :

Box 30003, Dept. 3Q
Las Cruces, NM 88003.

You can call them at (575)646-4422 or Fax to (575)646-5185.

For more information, see the SWAT Lab website.

Your local NMSU County Extension Service office can give you information regarding proper soil sample collection and can help you with soil test results interpretation.
There are other (commercial and university laboratories), but NMSU's lab has experience and techniques adapted for New Mexico soils. It is important to get the appropriate sample submission form from the lab you will use and follow their specific instructions.
Proper soil sample collection is important. It is important to collect a random sample (many samples from randomly selected sites from across the garden area). If there are obvious differences in the soil, or if some areas produce plants with a different appearance (color, size, etc.) than other plants of the same type in different parts of the garden, a separate sample should be collected from each of those areas (resulting in two or more soil samples and potentially different recommendations for the different areas).
Approximately one pint of soil should be collected for each sample to submitted. Remove the grass, weed, or other plant debris layer from the top layer of the soil, then spread the soil on newspapers to dry. The sample will be less expensive to mail if it is dry and the soil testing lab will spend less time drying your sample if you have pre-dried it.
Put the sample into an appropriate container (bag or special container as required by the lab you choose), put this into an appropriate mailer (box or envelope) with your sample submission form. Follow the instructions from the laboratory regarding payment (either enclosed or sent separately) and mail the sample to the laboratory.
More detailed information for collecting a soil sample is available from you local NMSU Extension Service Office or within Guide A-114: Test Your Soil.
After the sample is analyzed, you will receive a report and your local NMSU Extension Service office will also receive a copy (if you chose the NMSU SWAT Lab). Because they also have a copy, they will be better able to help you if you have questions regarding proper treatments for your garden.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.


For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook page.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!