What is the difference between a moisture meter and a tensiometer?
Moisture meters estimate the volumetric moisture content of a material based on the dielectric constant of the substrate.
Tensiometers provide a measure the force required to obtain water from soil. Tension is a direct measure of the force a plant has to exert to obtain water from soil.
Moisture content alone is not a measure of water available to the plant. This because the size of the pores in horticultural materials affects how water is made available to plant. Materials with large pores (such as sand, wood chips, perlite, clay balls, or spun granite) are comprised of large pores and release water at a very low tension. Materials such as clay, coir, biochar, compost contain finer pores and these require more force to drain them.
It is possible to establish the relationship between tension and moisture content for any given soil. This relationship, often call a moisture release curve. These curves are typically measured under highly standardized conditions to allow for accurate comparison between materials, but the values often do not translate well into the greenhouse, especially when the material is close to saturation.
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Which tool do you recommend I use to measure the moisture content of bio365 media?
bio365 soils release water across a wide range of tension, allowing for dry backs during crop establishment with low risk of wilting and providing options for fewer waterings and use of strategies to dry stress the plant, if desired during later ...
What is a tensiometer?
A tensiometer is used to measure the force required to obtain water from soil: known as soil moisture tension, soil water suction, or soil matric potential. A porous ceramic cup or tube is buried in the soil at the depth of interest. This ceramic cup ...
What is a moisture meter?
There are two main types of sensors that measure the volumetric water content in soilless media: Time Domain Reflectometry (TDR) and Capacitance. Both types of sensors measure the dielectric constant of the substrate. The dielectric constant is 1 for ...
Does the presence of biochar in your media affect how I should measure soil moisture and other properties?
Biochar has an inherently high electrical conductivity. This conductivity may interfere with soil measurements. We have occasionally seen erroneous measurements with push in type pH and EC meters as well as TDR moisture meters. While infrequent, it ...
Do you recommend a specific type of water?
We do not, but it is important to understand the quality of water being used in horticulture. In particular, you should understand the alkalinity of you water and presence of any minerals. If you have a high ppm water source, we recommend treating ...