Local Soil Testing Service?

Q. I have an 8-foot x 8-foot raised bed garden about 3 feet deep. I used a soil mix with a rich compost about three years ago. I added rock dust and steer manure to the soil over the last two years. I would like to test it now before adding anything more. Are there any local soil testing laboratories I can use?

A. There are at least two Las Vegas soil testing laboratories that can do this kind of work, but they specialize mostly in soils for construction and environmental protection.

http://geoscience.unlv.edu/ESAL/ESAL.html

https://www.ssalabs.com/services/

Las Vegas is not an agricultural community. I think the local laboratory is more expensive compared to existing agricultural soil testing laboratories and you must specify with them what you need done. Plus they have a minimum numbers of samples that must be submitted for the quoted price. It would be a good idea to do some comparison shopping.

            When shopping for a soil testing service, know what you want done. They analyze a soil for its structural and chemical properties. For a small fee they include a computer-generated response about results, how to correct the soil if there are problems and what to add to it if it’s lacking something. I would recommend getting it.

            Select a soil testing service that does a lot of desert agricultural soil testing. Selecting an agricultural soil testing service in Florida for instance may not give you desert appropriate feedback. I am comfortable with soil tests from A and L Agricultural Soil Testing Laboratory in Modesto California, IAS or Motzz Laboratories in Phoenix and Waypoint Analytical in Los Angeles. I’m sure there are others as well. Any of them would provide good information.

            Some people may cringe when I say this but if you are careful and have analytical skills, the home soil testing kits are not bad and give you a rough approximation of nutrients and the chemistry of your soil.

            My last piece of advice when taking and submitting a soil sample is, “garbage in – garbage out”. You must sample the soil from several random locations in your raised bed and mix them together. Use extremely clean tools and soil sampling containers. Sample the soil to a depth you know is actively supplying plants with nutrients. In your case, if you’re growing vegetables and herbs I would sample to 12 inches deep only.