SILICIUM Si(OH)4

Description

Silicium Si(OH)4 is a bioavailable silicic acid supplement that provides plants with a directly absorbable form of silicon — one of the most beneficial yet consistently overlooked elements in high-performance plant nutrition. We have been recommending silicon supplementation to UK growers since 2017 as a genuinely evidence-based approach to improving plant structural integrity, stress tolerance, and resistance to both biotic and abiotic challenges. Si(OH)4 — orthosilicic acid — is the specific form of silicon that plants can actually absorb and utilise, making this product more effective than stabilised silica alternatives.

The Science Behind Silicon Supplementation with Si(OH)4

Silicon is the second most abundant element in the earth’s crust, but most of it exists in forms that plants cannot absorb. Plants take up silicon exclusively as orthosilicic acid — Si(OH)4 — through the root system. Once absorbed, silicon is deposited in cell walls, particularly in the epidermal cells of leaves and stems, where it forms a physical barrier that significantly increases resistance to fungal pathogen penetration — including powdery mildew and Botrytis — and reduces damage from pest feeding. Silicon also improves physical stem strength and resistance to lodging under the weight of heavy flower heads, improves drought tolerance by reducing transpiration water loss through reinforced cuticles, and has been shown to mitigate heavy metal toxicity in contaminated growing media. Research consistently shows that silicon-supplemented plants produce larger, denser flowers with measurably improved structural integrity. Silicium Si(OH)4 provides this element in the immediately bioavailable form that translates directly into these benefits.

How to Use Silicium Si(OH)4 in Your Feeding Programme

Add Silicium Si(OH)4 to your nutrient solution at the recommended rate — typically 0.2–1 ml per litre depending on growth stage. Always add to the reservoir before other nutrient components, as silicon can interact with calcium and other elements at high concentrations. Mix thoroughly before checking and adjusting pH. Start at lower rates during seedling and early veg stages and increase through vegetative growth and flowering. Silicon supplements raise pH and require downward adjustment after addition. Regular use from early veg through to the final weeks of flower provides the full structural and protective benefits the element offers.

Pair Silicium Si(OH)4 with your base nutrient programme and a beneficial bacterial inoculant for a complete approach to plant health and structural development. Browse our full range of nutrients and additives for the best-performing gardens.