hOW TO SUCCESSFULLY CHOOSE GROWING...
There are many advantages to using growing media:
• High yields can be achieved in a limited area
• Better control over irrigation and fertilization
• Easier disinfection
• Recycling of drainage water is possible
• Growing media can be used as an alternative to an
inadequate soil
However, there are also some disadvantages:
• Nutrient-holding capacity is low
• Buffer capacity is low and, therefore, changes are rapid
In this report, we focus only on the physical properties. The
chemical properties will be discussed at a later date.
“
Physical and chemical
properties of growing media differ
from those of soil, and container
production requires more attentive
management.
Physical
”
properties of
the growing
media
A balance between air content
and available water is one of the most important requirements
of good media. Ideal growing media provide plants with
adequate water supply and, at the same time, contain enough
air to allow gas exchange and oxygen supply in the root system.
Aeration is critical for optimum plant development, as a lack of
adequate aeration results in poor plant growth, susceptibility to
diseases and nutrient deficiencies.
Good growing media are also characterized by high hydraulic
conductivity—that is, the ability to transmit water. Another
important property is the medium’s weight. It should be light
enough for easy and less expensive transport and handling, but it
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Maximum Yield USA | September 2012