PLACING IN STORAGE
If you want to place the Sensetion in storage, for example after the growing season, the Sensetion needs
to be deactivated. Use the Dacom Advice app to
deactivate
the Sensetion. Click on the ‘+’ sign in the
overview, scan the QR-code on the back of the data logger and use the slider to deactivate the Sensetion.
Don’t forget to save changes. You can also deactivate the sensor in the web application.
If the Sensetion will not be used for a prolonged period of time, the Sensetion should be placed two
entire days outside in the sunlight once a month. This will prevent the batteries from being discharged
excessively and ensures a longer lifespan of the batteries.
PUTTING IN USE AT THE START OF THE NEW GROWING SEASON
One week before the start of the new growing season, you should place the Sensetion outside in the sun
to ensure it’s fully charged.
TECHNICAL EXPLANATION OF SOIL MOISTURE
SOIL MOISTURE SUPPLY
The total amount of moisture a soil can contain, depends primarily on the particle size distribution within
the soil and the organic matter content. Only a portion of the total amount of soil moisture is readily
available to the plant. We call this the ‘readily available soil moisture’. The crop should be irrigated once the
amount of readily available soil moisture is likely to become too low. The soil moisture deficit determines
the number of millimeters to be irrigated. Irrigating more than the deficit will cause water (and nutrients) to
seep away beyond the reach of the roots or may cause ponding and runoff.
SOIL MOISTURE TERMS
Field capacity (FC):
is the amount of water that a saturated soil can still retain after 2 to 3 days against
the force of gravity. The field capacity influences the availability of water-soluble nutrients for the plant,
the flushing of nutrients and the irrigation. Once the field capacity has been reached, the soil is not yet
completely saturated with water. There is still air in the large- and medium-sized pores. So, in case of
precipitation it is possible for the soil to contain more water than at field capacity.
Saturation:
occurs when all the voids in the soil are completely filled with water. Although there is a lot of
water available for the crop, the water uptake will be very limited due to the lack of oxygen. If the
situation in excess of the field capacity persists, the plant will die.
Wilting Point (WP):
the (permanent) wilting point is the level of moisture content of the soil where the
plant is not able to absorb any more water from the soil and, therefore, will wilt and die.
Maximum Available Soil Moisture (MASM):
is the difference between the amount of soil moisture at field
capacity and the amount at wilting point.
Refill point:
the point at which irrigation should be applied to avoid stress to the crop. Beyond this point
the daily uptake of water by the plants is reduced because it requires more pressure (suction) to move
water into the plant. A plant will be limited in its production as it closes down stomata to avoid
dehydration. Some crops require some stress in certain stages of the crop development.
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