Testing Soil Salinity

A truly successful gardener will not only know how to make compost and grow plants but they will also be very familiar with the properties of their soils as well.  The knowledge of soil pH, salinity and other factors are very important in determining what can grow where in your garden.  To that end you should know how to test soil salinity in your garden soils.  Testing salinity is easy enough to do if you have the right tools like a soil meter capable of measuring electrical conductivity.  They are easy enough to find can be found on Amazon for around 20 dollars.  ​

Saturated Paste Method  The most common field method for testing soil salinity is called the saturated paste method.  I will outline the basics of doing this test but the specifics will vary according to the meter you get.  It is very important that you follow the directions that come with the meter because is you don’t the results could be skewed.

Step 1
If you are testing a specific spot collect a sample of soil from that spot.  You will need anywhere from a tablespoon to a quarter cup of soil for the test.  If you want a general picture of your whole garden you will need to either collect and mix multiple samples or do multiple tests at different spots.

Step 2
Crush up and powder the soil until it is finely broken down into the smallest particles you can get it into.  I would typically use a sturdy spoon and a tough plastic or glass cup as a container to grind the soil in.  You should also remove any rock or large bits of organic matter from the sample.

Step 3
Add either distilled water or rain water to the cup at a ratio specified by the meter.  I have seen directions indicating water amounts to be as low as 1:1 water to soil and as high as 4-5:1.  When doing this step it is very important you used distilled water and only enough water as indicated by your meter.  If the water amounts are not accurate then it will throw off the results.  

Step 4
After the soil and water have been fully mixed then place the meter in the water and wait for around 10 seconds before taking a reading.  The number will take a little bit to settle on a figure and you may have to average between a low and high reading.


Step 5      
Depending on your meter you may have to convert the reading to a number you can use.  The conversion factor is dependent mainly on soil texture which you will have to know.  If you don’t know your soil texture you can can find a guide on how to do it here.


After you have the reading is important that you clean the meters electrodes off with more distilled water.  Once clean go ahead and put the cap back on and put it way until your next test.


Doing a salinity test is an important part of determining the suitability of growing food on your land so it would be a good idea to pick of a meter.  Having a meter on hand will allow you to figure out problem spots before you try and grow something which will save you time and money.    


Sources:
http://extension.uga.edu/publications/detail.cfm?number=C1019#Collecting


http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0008/168866/texture-salinity.pdf


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