Therm-O-Rock Super Coarse Horticultural Vermiculite
Best soil amendment for organic gardeners seeking superior root development.
This super-coarse mineral is the secret to professional-grade soil structure, providing the perfect balance of aeration and moisture retention. While it adds a bit of bulk to your storage space, the boost in root health and overall plant vigor makes it an indispensable tool for any serious gardener.
$35.00
at
Hummert
More Therm-O-Rock Vermiculite options
Who it's for
- Gardeners struggling with heavy, compacted soil
- Busy plant owners needing less frequent watering
- Propagators seeking a sterile, reliable starting medium
Who should skip it
- Long-term growers requiring permanent soil structure
- Budget-conscious gardeners managing large-scale projects
- Seed starters working with tiny, delicate varieties
Performance breakdown
Aeration Efficiency
Super coarse grade creates ideal air pockets for vigorous root respiration.
Moisture Retention
Superior absorbent capacity keeps hydration consistent during peak growing cycles.
Organic Integrity
OMRI listing ensures complete compliance for strictly organic gardening standards.
Handling Ease
Lightweight mineral composition makes mixing large batches physically effortless.
Soil Structure Impact
Significantly improves soil porosity for better nutrient uptake and drainage.
Purity Standards
Weed-free mineral base eliminates risk of introducing unwanted garden contaminants.
Key Specs
Weight
40 lbs
Volume
4 cubic feet
Grade
Super Coarse
Certification
OMRI Listed
pH Level
7.0
Soil Type
Potting Mix
Drainage Level
Fast Draining
Moisture Retention Level
High
Texture
Coarse
Primary Amendment
Vermiculite
Know before you buy
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Ask Metto anything about the Therm-O-Rock Super Coarse Horticultural Vermiculite before you decide.
