Plant and Soil Science
Standard 4 Objective 2

 When raising plants there are many different options for a growing media
 Most of the time think all plants grow in soil
 This is not the case
 Does anyone know the kind of growing media we commonly use in our greenhouse?
 Is is soil? or a Soilless media?


Soil (loamy, good structure, pesticide-free)
 Coarse aggregates for drainage (sand, perlite, vermiculite, shredded plastics)
 Organic amendments to hold water (sphagnum peat moss, tree bark, sawdust, rice hulls, shredded coconut hulls, wood chip/sludge compost)
 Most contain no soil

Advantages of Soilless Mixes
 sterile
 lightweight
 good moisture retention and drainage
 free of weed seeds

Disadvantages of Soilless
Mixes
 minor elements are missing
 light weight - pots tip in strong wind
 transplants may not adjust well to new media

 Soilless mixes contain various combinations of the following materials.

 improves aeration
 of volcanic origin

 Dehydrated remains of acid bog plants
 Used to cover seeds because it is lightweight, controls disease, and holds moisture.

 Partially decomposed underwater vegetation.
 Holds moisture well
 Low in nutrients

 Exploded Mica
 Improves aeration
 Holds moisture very well

 Raises pH



Technique of growing plants in non-soil medium using feeding mixture of essential plant nutrients dissolved in H
2
O
Three main types


 static solution culture medium culture aeroponics