Maintaining soil moisture at optimum levels can increase crop yield and profits by: maximising nutrient & mineral availability; ensuring fertiliser is not flushed from the root zone; reducing disease susceptibility; increasing oxygen levels in the soil; improving soil structure; minimising the effects of moisture stress; maximising fruit size and quality.
Available water for the crop
It is important to realise that the same percentage amount of water in different soil types yields vastly different amounts of ‘available’ water for the crop.
An instrument that gives a direct indication of water availability (i.e. how difficult it is for the crop to draw that moisture from the soil) would therefore be much better than one which indicates the actual percentage of water in the soil.
Capacitance and some other probes indicate the percentage of soil moisture, whereas tensiometers (such as the Soilspec Tensiometer System) indicate soil moisture availability.
Soil moisture control
The combination of an accurate soil moisture measurement tool and a good irrigation strategy will allow for informed decisions to be made.
The record of soil moisture readings will also give an understanding on how changing conditions affect the water requirements of the crop and help plan future irrigation strategies.
Measuring soil moisture can be expensive and difficult, but tensiometers are still a simple, cost effective and reliable method to measure soil moisture availability.
For contact information, see Tree Fruit March 2016
