Soilless Growing Media
By: Johnny M. Jessup
Agriculture Teacher/FFA Advisor
Soils & Growing Media
• Made up of two types of materials….
• Organic Matter
• Inorganic Compounds
Organic Matter
• Dead plant or animal tissue.
• Contains carbon.
• Usually has diseases or insects.
Types of Organic Matter
• Compost
• Mixture of partially decayed organic matter.
Types of Organic Matter
• Bark
• Particles too
large to use
in seed
germination
media.
Types of Organic Matter
• Mulch
• Material placed on soil to break the fall of
raindrops (prevents erosion), prevent
weeds from growing, or improve the
appearance of the area.
• Used to cover soil to help hold moisture
and prevent weeds.
Mulch
Types of Organic Matter
• Straw
Types of Organic Matter
• Peat Moss
• Type of organic matter made from
sphagnum moss.
Types of Organic Matter
• Sphagnum
• Pale & ashy mosses used to condition soil.
Types of Organic Matter
• Sawdust & Wood Shavings
• High carbon to nitrogen ratio that makes
nitrogen unavailable for plant use.
Inorganic Compounds
• Do not contain carbon
• Usually sterile.
Types of Inorganic Compounds
• Soilless Media
• Artificial soil.
• Perlite
• Natural volcanic material.
• Helps aeration.
• Improves water-holding capacity.
Perlite
Vermiculite
• Vermiculite
• Mica mineral matter used to start seeds
and cuttings.
• Helps hold moisture.
• Has neutral pH.
pH
• Most organic matter is acid.
• Most artificial media is neutral.
Hydroponics
Hydroponics
• The process of
growing plants
without soil.
Types of Systems
• Aggregate System
• Using sand or gravel to support plant roots.
Types of Systems
• Water Culture
• Also called solution culture or nutriculture.
• Plant roots grow in water containing
dissolved nutrients.
Types of Systems
• Aeroponics
• Plant roots hang in air and are misted
regularly with a nutrient solution.
Types of Systems
• Continuous Flow System
• Nutrient solution flows constantly over plant roots.
• Most commonly used for commercial production.
Advantage of Hydroponics
• No soil & problems associated with soil.
• Easy to control nutrient content of plants.
Disadvantages of Hydroponics
• Plant support must be provided with
strings, wires, or stakes.
• Water quality must be high.
• Diseases spread through water.
• More moisture or humidity in air to
cause favorable environment for
disease organisms.
• More expensive.
Hydroponic Lettuce
Designed By:
• Johnny M. Jessup; FFA Advisor
• Hobbton High School