The document discusses the purposes that soil and other planting media serve for plants. It notes that media provide structure to help plants stay in place, a habitat for beneficial bacteria and worms to live near the plants' roots, and a means to trap nutrients from animal waste as well as water and air close to the roots. Media also act as a protective shield for roots against large temperature changes. The key is choosing a media that fulfills these roles of structure, supporting microbes and animals, nutrient retention, and temperature regulation for optimal plant growth.

1. Media
What are our plants
growing out of?
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2. Why do plants grow out of dirt?
A lot of reasons!
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3. Plants need structure
They like to stay in place! They do not like to move.
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4. Bacteria (tiny organisms) help
plants get nutrients!
Bacteria need
a place to live
near the
plants
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5. Worms help plants get nutrients
too!
They need to
live near the
plants
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6. Urine and feces from animals have
nutrients for the plants
The soil or
media traps
these near
the plants
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7. Plants need water and air nearby!
Air
Water
Soil and
media hold
them close
to the
plants
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8. Plants do not like big temperature
changes
Dirt and media
protect the roots
from big changes
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9. Make sure your media has these!
• Structure – use materials that would help a plant
stay still.
• Bacteria – make sure there is surface area for
bacteria to live, remember bacteria are very small!
• Worms – worms should be able to move within the
media.
• Urine, feces, water and air – all of these should be
trapped within your media.
• Temperature – the media should be a “shield” to
the roots against temperature change, make sure
roots would not be exposed!
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