October 2019 - 20

RESEARCH
SEEING
INSIDE YOUR
Container
Media
Figure 1. This basil plant
is growing in a compacted
black peat with nutrient film
technique (NFT) hydroponics
resulting in water-filled pores
and few air-filled pores.
SPONSORED BY
It can be challenging to visualize your substrate, but becoming familiar
with its physical properties can help you grow healthier plants.
BY PAUL FISHER, ERIN YAFUSO AND ANA BOHORQUEZ
W
hen you buy a good-quality root substrate, you are mostly
purchasing holes. Solid particles from peat, bark, perlite, wood
fiber and other components typically make up only about 20 to
30% of volume when a pot is filled with root substrate. The rest is made
up of spaces, termed pores, which are filled with either air or water.
If we can match our irrigation practices with a substrate with adequate
components and particle sizes, it results in a suitable balance of waterand
air-filled pores for healthy root growth. It is difficult to visualize
substrate physical properties such as porosity, but pores have a major
effect on plant performance. In this article, we will try to help you see
pores in a new light.
20 OCTOBER 2019 GPNMAG.COM
GOLDILOCKS SUBSTRATE - NOT TOO FINE,
NOT TOO COARSE
If you have ever received a shipment of fine, dusty container substrate,
then you may have experienced that the substrate is hard to dry down
and holds excess water. This is because fine particles lead to small pores
that are easily water-logged by irrigation, thereby starving plant roots
of oxygen and promoting disease. For example, if a fine and compacted
substrate is used in hydroponics where the substrate is continually
saturated, root growth will decrease (Figure 1).
In contrast, if the substrate is very chunky, the resulting pores are
large and filled with air rather than water. Use of large particles, such

http://www.GPNMAG.COM

October 2019

Table of Contents for the Digital Edition of October 2019

October 2019 - 1
October 2019 - 2
October 2019 - 3
October 2019 - 4
October 2019 - 5
October 2019 - 6
October 2019 - 7
October 2019 - 8
October 2019 - 9
October 2019 - 10
October 2019 - 11
October 2019 - 12
October 2019 - 13
October 2019 - 14
October 2019 - 15
October 2019 - 16
October 2019 - 17
October 2019 - 18
October 2019 - 19
October 2019 - 20
October 2019 - 21
October 2019 - 22
October 2019 - 23
October 2019 - 24
October 2019 - 25
October 2019 - 26
October 2019 - 27
October 2019 - 28
October 2019 - 29
October 2019 - 30
October 2019 - 31
October 2019 - 32
October 2019 - 33
October 2019 - 34
October 2019 - 35
October 2019 - 36
October 2019 - 37
October 2019 - 38
October 2019 - 39
October 2019 - 40
October 2019 - 41
October 2019 - 42
October 2019 - 43
October 2019 - 44
October 2019 - 45
October 2019 - 46
October 2019 - 47
October 2019 - 48
October 2019 - 49
October 2019 - 50
October 2019 - 51
October 2019 - 52
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/new-varieties-digital-guide-2025
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/2024-guide-to-cannabis-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/new-varieties-digital-guide-2024
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-april-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/2023-guide-to-hemp-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/2023-guide-to-cannabis-production
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-december-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-october-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/gpn-new-varieties-digital-guide-2023
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-april-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/newvarieties-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2022
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/newvarieties-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2021
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/californiaspringtrials-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/cannabisguide-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/hempguide-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2020
https://www.nxtbook.com/greatamericanmediaservices/GPN/december-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-november-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/november-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/october-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-september-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/september-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/august-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-july-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/july-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/june-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/may-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/april-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/californiaspringtrials-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-march-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/march-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/february-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/undercontrol-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/big-grower-january-2019
https://www.nxtbook.com/greatamericanmediaservices/GPN/january-2019
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