1. Hydroponics
Objective: Introduce students to growing plants in nutrient solutions

2. What is hydroponics?
Practice of growing plants in _______ solutions with or without the use of _______ medium to provide mechanical support
Types
Liquid systems – no support medium for roots
Aggregate systems – have a solid medium of support: _________, sand, gravel, vermiculite
Open - nutrient solution not reused after delivery to plant roots
Closed – surplus solution is recovered, replenished, and recycled

3. Hydroponics – pros and cons
Eliminates soil borne ________
Allows control of water and nutrients
Higher quality plants with ______ and higher yields
Able to grow vegetables in areas where otherwise is impossible
Cons
Management is _______
High costs if heating & artificial lights are needed
_______ kcal for 1 kg tomatoes in greenhouse versus 1,865 kcal to ship 5000 km
Equipment expense

4. The Hanging Gardens of Babylon
The floating Gardens
of the Aztecs of Mexico

5. History of hydroponics
Controlled environment agriculture (CEA) first used for growing ________ under mica in 1st century
Greenhouses & experimental hydroponics appeared in _______ and England during 17th century

6. History of hydroponicsUS
New Jersey Agricultural Experiment Station improved sand culture method
California Agricultural Experiment Station used _______ and sand culture methods for large scale production
__________& Arnon develop complete nutrient solution

7. History of hydroponics
Some use of hydroponics on _________ Islands during World War II
______ popularized nutriculture (hydroponics) in the post-war period

8. History of hydroponics
High energy costs in early 1970’s caused widespread ___________
Late 1960’s: nutrient _______ technique developed

9. Types of hydroponic systems
Ebb and flow systems
Continuous drip systems
__________ systems
Nutrient film systems
______ systems
Water culture

10. Ebb and flow systems Floods growth tray with nutrient solution
Drains solution into reservoir
Pump and timer failures can dry out ______
Uses medium such as _________ or rock wool to retain water

11. Continuous drip systems
Most popular
Nutrient solution dripped out to based of plant

12. Aeroponic systems
Nutrient solution sprayed onto roots in ______ chambers where roots are suspended in _____
Used at Epcot Center at Disney World

13. Nutrient film systems
Constant flow of nutrient solution through growing tray
Solution ________
Roots are inside bag and hang in air when no solution recycled

14. Wick systems Simplest design
Nutrient solution drawn into growing area through _____
Large plants use nutrient solution faster than wick can provide

15. Water culture systems
Plants grow on platform with roots suspended into solution
_______ bubbled into nutrient solution to provide oxygen for roots
Does not work well with _____ plants or long-term growing

16. Growing vegetables and herbs
Common – lettuce, _______, cucumber
Rapid growing, good taste, high yield
Tomato sometimes lack _______ Why?
Herbs
Common – basil, sage, ________, mint
Lack smell and taste