Your SlideShare is downloading. ×
Soilless mixes
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.


Saving this for later?

Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime - even offline.

Text the download link to your phone

Standard text messaging rates apply

Soilless mixes


Published on

Basics on soilless growing media. Physical, chemical characteristics and other attributes

Basics on soilless growing media. Physical, chemical characteristics and other attributes

  • Be the first to comment

  • Be the first to like this

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. It all depends…. SOILLESS MIXESKevin Donnelly, CH.
  • 2. GROWING MEDIA Air Water Structure Nutrient Reservoir
  • 3. THE IDEAL MIX It all depends…. Fits your growing style Produces quality plants with limited management Consistent/Predictable Cost effective
  • 5. MACRO VS. MICROPORES 30% Air 75% Water 45% Water 25% Solids 25% Solids
  • 6. CAPILLARY ACTION IN MIX Important when sub irrigating containers Pores act as a straw and
  • 7. ZONE OF SATURATION Amount mix will hold at the bottom
  • 8. CONTAINER SIZE Size and Shape of container can effect water air water relationships  Look at the force of gravity 45% Air 25% Air 10% Air
  • 9. BULK DENSITY/ COMPACTION Depending on how it is filled can impact air water relationships Compact vs. lightly filed
  • 10. SHRINK Settling after watering Component breakdown Out the bottom? Shrink from blending
  • 11. WHY IT MATTERS Overwatering or under watering causes issues Pick up method of checking watering status  If I change the weight of your mix, you will mess up  Surface may dry up but not underneath  Knock out pots to check
  • 12. WETTING AGENT Aids in wetting up mix  Peat is hydrophobic Helps with even watering,  Not channeling down the sides of the pot A good idea for postharvest quality
  • 14. PH Will effect nutrient availability Fluctuates over the course of the crop The plant causes pH changes Alkalinity of your water is important  May need to do acid injections Buffer capacity of your components Lime and Iron Sulfate
  • 15. PH
  • 16. EC AKA soluble salts Measure of salt content in solution Can be from good salts or bad Many use EC as indication of fertility Listed in dS/m or ppm (dS/m X 670) Dilution method matters!!
  • 17. NUTRIENTS Minerals/non coated  dolomite lime  Iron Sulfate Controlled Release Fertilizers (CRF or SRF)  Encapsulated NPK+ Organic Fertilizers  Often have low analysis and low availability (predictable)
  • 18. OTHER MEASURMENTS Organic Matter CEC C:N Weed Seed presence Wettability Moisture content
  • 19. TESTING What do you test for How Often How do you test  Interal testing  External lab What do you do with that information
  • 20. SAMPLING How you sample may add bias to the test Area of pot  Top 1/3rd  Middle 1/3rd  Bottom 1/3rd Random sample or targeted sample
  • 21. TESTING FOR PHYSICAL PROPERTIES Air Porosity  Field Method  NCSU Porometer Sieve analysis
  • 22. TESTING CHEMICAL In house  EC  pH External Lab  Nutrients  CEC  Etc.
  • 23. EC Method maters  1:1  2:1  SME  Pour Thru Many use it for managing fert  If EC reading falls below X, then fertigate
  • 24. PH TESTING Moving Target Can be adjusted 7 6.5 6 5.5 5 4.5 4 1 2 3 4 5 6 7 8 9
  • 25. BIG POINT FOR ANY TESTING Don’t make major changes right after testing starts to correct issues that may be normal Need historical values to see what is your norm Plants don’t read test reports
  • 26. BIOLOGICAL Mycorrhizae Benificial bacteria/fungi These can be incorporated into mix  As well as some pesticides
  • 27. Its all about logisticsCOMPONENTS
  • 28. AGGREGATES Perlite  Others Vermiculite  Lava  Glass Sand  Polystyrene Calcined clay  Rockwool  Oildri  LWA
  • 29. ORGANIC COMPONENTS Peat  “Composts”  Landscape compost  Sphagnum  Manure compost  Reed Sedge  Biosolids Pine  Worm Casting Rice  Mushroom “Compost” Coir  Spent Mushroom Substrate
  • 30. NEW PRODUCTS Why we need them  Look for local  Price  Cheap  Availability  Effective  Quality  Sustainability These are not replacements
  • 31. NEW FRONTIERS Whole Tree Substrate Corn Cobs Miscanthus Biochar
  • 32. MANAGING RAW COMPONENTS These are natural products They vary They change over time How you manage them maters