Soilless Growing Media
By: Johnny M. JessupAgriculture 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