Improve Soil and Strengthen Crops

Energize your soil with Sigma Si, a natural source of plant available silicon that improves soil and strengthens crops, and can result in higher yields and increased profits.

Silicon Benefits

Whether monoculture, high production demands, climate issues, degraded soils, or diseases and pests; silicon provides unique, multifaceted beneficial effects in assisting plants in dealing with stress. Silicon is also proven to increase:

  • Plant Cell Wall Strength
  • Photosynthesis
  • Disease Resistance
  • Pest Resistance
  • Flood Tolerance
  • Nutrient Balance
  • UV Tolerance
  • Drought & Salt Tolerance
  • High & Low Temperature Tolerance
  • Carbon Sequestration
  • Ability to Regulate the Uptake of Heavy Metals

“Sigma’s new line of granulated Silicon products utilizes Ignimbrite Si14 Inside technology to provide a natural source of plant available silicon that is easily incorporated into existing nutrient management plans.”

Silicon is a beneficial substance

Silicon is categorized as a “beneficial substance” by the Association of American Plant Food Control Officials (AAPFCO). AAPFCO defines a “beneficial substance” as “any substance or compound other than primary, secondary and micro plant nutrients that can be demonstrated by scientific research to be beneficial to one or more species of plants when applied exogenously.”

Silicon, though not considered an essential plant nutrient, is essential to present-day agricultural production systems and is scientifically proven to benefit various multi-cropping systems.


Sigma Si Granules are easily incorporated into existing nutrient management plans with a variety of blends and formulations for Agriculture and Specialty Solutions applications.

  • Sigma Si Granular (100% Ignimbrite Si14 Inside)
  • Blended Sigma Si Granules with other Organic Inputs
  • Blended Sigma Si Granules with Traditional NPK Inputs
  • Blended Homogeneous, Organic, and NPK Fertilizers


  • Conventional Farming
  • Greenhouse
  • Orchards
  • Organic Farming
  • Vineyards

Specialty Solutions

  • Ornamental and Nursery
  • Golf Courses
  • Sports
  • Landscape
  • Sod Farms


While silicon comprises 27% of the earth’s crust, most soils have limited supplies of this element in a form that is plant available silicon, known as silicic acid. The majority of silicon is found in crystalline forms like sand or quartz, and is not soluble or readily available for plant uptake. Instead, it takes centuries of weathering to break down silicon into a plant available form.

It is estimated that every year, over 21,000,000 million tons of plant available silicon is removed from U.S. soils by harvesting principal crops without being adequately replaced. This results in an alarming crop deficiency of plant available silicon. Volcanic ash is one of the only sources of plant available silicon naturally deposited into soils, a cycle and process that can take millions of years. Ignimbrite is a volcanic tuff that provides all the benefits of silicon in a plant available form.


Ignimbrite is Latin for “fiery rock dust cloud”, a result of an immense explosion of pyroclastic ash that flowed down the sides of volcanoes. Ignimbrite Si14 Inside™ technology is derived from an ancient deposit of high-energy volcanic tuff mined in Montana that contains 76% amorphous silicon and other beneficial macro and micronutrients.

When viewed under a microscope, the Ignimbrite mineral demonstrates its unique sponge like porosity and non-crystalline formation.

Ignimbrite Si14 Inside™ guarantees a natural source of plant available silicon in the form of amorphous potassium mineral with a soft, porous, structure in variable particle sizes that weatherize easily, providing immediate and gradual release of Silicic Acid. Other benefits of Ignimbrite Si14 Inside™ include:

  • Conditions and improves soil texture.
  • Neutral pH and potassium silicate chemistry allows for application on soils where like is not required and high sodium or aluminum is an issue.
  • No shelf life limitations, easy to apply, and does not polymerize.
  • Adjuvant that reduces nitrogen volatility and improves phosphorus availability.
  • Non-Crystalline structure with dual Hydrophobic and Hydrophilic properties.
  • High Cation exchange capacity increases absorption and adsorption capabilities.
  • 3.5 on the MOHS hardness scale allows mineral to easily break down with weathering.
  • Chemical free, does not burn plants, and is OMRI Listed.