Gypsum Blocks & Meters

They may look like nothing more than marshmallows on strings, but Gypsum Blocks can be a grower’s best friend when it comes to finding out what’s going on below the surface of fields. The Gypsum Block system is a valuable tool in monitoring the soil moisture available to the plants. This system eliminates guesswork so that irrigation can be effectively scheduled according to plants' requirements, decreasing the potential for over irrigation, under irrigation, and deep percolation.

Gypsum blocks have been around since the 1940’s and are not much more high tech than they look. Made of gypsum, cast around two stainless steel electrodes: they work according to the theory of conduction. At about $6 per block, it is also one of the cheapest methods of soil moisture measurement. And because the grower can read the gypsum block manually with a hand-held reader (about $150, and a one time purchase), the cost per measurement point remains the lowest in the industry. It is extremely simple and is well worth the investment of time and labor.

Simple Installation and Operation:

 The blocks are buried in representative areas in the field to monitor soil moisture changes in the area of active root growth. Gypsum blocks should be installed as soon as possible to allow time for plant roots to grow around the blocks. Blocks installed late in the growing season may not provide accurate readings. They are buried at one or more levels, depending on the crop and the depth of the root zone. When the blocks' lead wires are connected to the meter, an indication of the available soil moisture is immediately obtained on the meter display.

The cost of keeping track of soil water on your own or by using a service can be paid back through the benefits of effective water management. Included among these benefits are energy savings, water savings, water quality improvement, and quite often improved crop quality and yields.

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