VanSil Wollastonite — Natural Calcium Silicate Fertilizer

VanSil wollastonite by Vanderbilt Minerals is the only OMRI-certified wollastonite mined and milled entirely in the USA — sourced from Lewis County, New York. Not a slag byproduct. The 20 lb size is ideal for market gardeners, small farms, and greenhouse operations incorporating silicon and calcium into regular fertility programs.

Use as a gentle lime alternative to raise media pH while delivering plant-available silicon (Si) and carbon-neutral calcium (Ca) to your root zone. Silicon strengthens cell walls, improves stress and pest tolerance, and enhances overall plant vigor without the pH spike risk of hydrated lime.

Guaranteed Analysis

• CaO: 45% | Ca: 34%
• SiO₂: 50% | Total Si: 24% | Soluble Si: 3.6%

Key Benefits

• Plant-available silicon — strengthens cell walls; improves stress and pest tolerance
• Gentle pH correction — raises media pH without the spike risk of hydrated lime
• Carbon-neutral calcium — no heavy metals, no slag
• OMRI Listed — certified for organic production under the NOP
• USA mined & milled — the only OMRI-certified wollastonite sourced entirely in the USA
• 20 lb box — ideal for market gardeners, small farms, and greenhouse programs

State restrictions: Not available for shipment to Oregon.