YOU WANT WET PLANTS, NOT SOAKED PLANTS
plant water requirements on incoming
light levels and computer models that
estimate crop transpiration.
Newer technology, much of which is
still under development for soilless
systems but is likely to be a beneficial
innovation for indoor gardeners, is
the use of plant-based sensing of
moisture status. Plant-based methods
of irrigation determination rely on
direct or indirect measurement of
plant water status based on plant
physiological responses to drought
using tissue water content sensors or
measurement of growth, sap flow and
stomata conductance. Measurement
of the water status of the plant itself
may be highly beneficial when growers
are using methods of controlled deficit
irrigation to direct growth in a certain
way, for example into more generative
and less vegetative growth, or to apply
some controlled degree of stress to
improve plant or fruit quality.
Substrate moisture sensors are one
way of irrigating to the plant’s actual
water needs rather than just relying
on pre-programmed, timed applications that may overwater or underwater
plants. Soil moisture sensors have been
in use in field crops for decades, but
more recent developments have seen
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Maximum Yield USA | October 2016
Some plants such as hydroponic water chestnuts require more moisture than other types of plants.