1. Growth Mediums

2. May store:
Water O2
Beneficial Organisms
Growth Mediums are a hallmark of hydroponic gardening
Generally do not change water chemistry
Provide place for germination
Typically selected based on technique, crop and preference.
Provide support for growth
Purpose

3. Coco Coir Made from brown husk surrounding coconuts
Sold in compressed bricks, expands with H2O
AKA: Coco, Palm Peat, Coir
Chemically/Biologically Inert
Extremely absorbent (6-8 x wt.), green
Can be mixed with Perlite for better drainage
Good with Drip & Dutch Bucket Techniques
Can be messy. Erosion-prone. Non-Reusable.
Coco Coir

4. Perlite Made from heated Silica
Lightweight, high porosity, excellent drainage
Keeps plants open to air (structure)
Chemically/Biologically Inert
Reusable, inexpensive, good mixing, green
Can move, float away, and clog systems, provides relatively little support
Perlite

5. Vermiculite Heated-treated Silicate (like Perlite)
Lightweight, H2O retention = 200%-300% by Wt.
Good and Bad
Natural wicking, good for passive systems
Chemically/Biologically Inert
Good mixer, inexpensive, Reusable (= work)
Can move, float away, and clog systems, provides relatively little support
Vermiculite

6. LECA Lightweight Expanded Clay Aggregate
Puffed Clay, generally 1/4” – 3/8” across
High porosity, excellent drainage, lightweight
Chemically/biologically Inert, green
AKA: Hydroton, Expanded Clay
Good for top drip, ebb & flow, DWC
Doesn’t retain H2O as well as Coco
LECA

7. Rockwool Made by spinning/blowing molten minerals (e.g.Basalt)
Lightweight, excellent H2O retention, fair O2 retention, variety of sizes
Non-green
Generally Inert (Can introduce slight pH elevation if not prepared properly)
Not reusable but can be recycled
Rockwool

8. No Medium

9. Fini