What Exactly Is Silica?
Silica (silicon dioxide, SiO₂) is the second-most abundant element in the earth’s crust, yet most potting mixes and hydroponic solutions deliver little of it. In plant biology, available silicon slots into cell walls like steel rods in concrete, adding mechanical strength and stress resilience. Think thicker stems, tougher leaves and a bigger safety margin when temps spike.
Why Aussie Growers Can’t Ignore It
Heat & Drought Tolerance
Our summer sun can push greenhouse temps past 40 °C. Silicon-fortified plants keep stomata functioning longer, limiting wilt and sunburn.
Pest & Disease Defence
A strengthened epidermis frustrates sap-suckers, while silicon triggers systemic responses against powdery mildew and botrytis.
Bigger Yields & Better Quality
Studies on capsicums, sugarcane and tomatoes show increased dry weight and higher Brix when silicon sits in solution from day one.
Nutrient Synergy
Silica improves uptake of calcium and phosphorus, reducing deficiencies that cause blossom-end rot or weak new growth.
The Two Heavy-Hitters: Potassium Silicate vs Monosilicic Acid
|
Feature |
||
|
Active form |
Potassium silicate (6 % w/v) |
Stabilised orthosilicic acid + amino chelates |
|
pH |
Alkaline – raises reservoir pH (adjust after dose) |
pH-neutral – no swing |
|
Concentration |
5 mL /L in hydro; 2–3 mL /L in soil |
15 mL / 100 L res; 1 mL /L foliar |
|
Key wins |
Cost-effective, ideal for large volumes |
Nano-size particles = rapid uptake; tighter internodes |
|
Best for |
Everyday protection & structural strength |
High-performance fruiting or stressed crops |
How to Use Silica (Step-by-Step)
A. In Recirculating Hydro
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Fill the tank with fresh water.
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Add silica first – before nutrients or Cal-Mag.
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Agitate, wait 15 min, then add base nutrients.
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Check pH; aim 5.5–6.2. Adjust if needed.
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Top up weekly.
B. In Coco or Soil
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Mix GT Silica at 2–3 mL /L.
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Water in until 10 % runoff appears.
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Repeat every second irrigation or as part of your regular feed chart.
C. Foliar Rescue
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Dilute Super-SI at 1 mL /L.
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Mist leaf tops and undersides during the night.
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Apply every 10 days during heatwaves or pest pressure.
Real-World Results
“My plants are already responding with more rapid, stronger growth… feels like silica was the missing piece.” – Susan M. on GT Silica
“Producing thick stems and side branches.” – Wayne J. on Super-SI
These aren’t isolated wins: both products average 4.8 ★ and keep turning first-time buyers into repeat customers.
Frequently Asked Questions
Will silica lock out other nutrients?
Not when dosed correctly. Add it before fertilisers, then balance pH and you’re golden.
Can I use both GT Silica and Super-SI together?
Pick one per cycle. Layering different forms risks over-supplementation without extra benefit.
Is silica “organic”?
Silica itself is a mineral element. Both products are free of synthetic PGRs and meet organic-minded gardeners’ expectations.
How soon will I see results?
Expect firmer stems within two weeks and noticeable yield or quality gains by harvest.
Does foliar spraying leave residue?
At the recommended 1 mL /L, Super-SI dries clear and won’t spot leaves or flowers.
Final Tips & Next Moves
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Start early: Silica works best when supplied from seedling through bloom.
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Monitor pH: Especially with potassium silicate – adjust after mixing.
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Stay consistent: Skip weeks and you lose the compounding strength benefits.
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Ready to trial?
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Grab a bottle of Growth Technology Silica for a cost-effective, all-round shield.
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Level-up with Super-SI Monosilicic Acid when you’re chasing elite yields or battling extreme stress.
Happy growing – and may your stems stand tall against whatever the Aussie climate throws their way.
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