Water Content

Water Content

The water content of the substrate provides the reservoir of the water and nutrients for the plant. Changing the water content is a usefull tool in controlling the plant balance and also maintaining root heath (How to change the water content).

In the Season Dynamics for each crop we suggest target levels for the water content for each of the critical periods. This is done for specific reasons in each period:

  • in long periods of low light levels it is better to run a lower water content as the plant is less active. This makes the slab more reactive and dry back faster to allow more oxgen into the slab and also give a generative action;
  • in high light levels with high transpiration levels it is best to run a higher water content to give more buffer for the higher water use by the plant. This also gives more safety in case of a breakdown.

The range of water contents used would be from 45% to 70%. The volume of substrate used is also a key factor (How much substrate do I use?)

Measure you slab in an organised way using a WET meter and set target water content objectives for the different periods.


“To control this water buffer to realize the potential of the slab in controlling the plant balance.”