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Frass by Grubbets® is an organic fertilizer and soil amendment for your home and garden that can be used in place of conventional synthetic fertilizers. Rich in nutrients and organic matter, Frass by Grubbets® will supply your plants and soil with wholesome and natural nutrition all season long without burning or leaching away.


Frass is the technical term for insect excreta (aka insect manure). Think of it like a combination of worm castings, guano, crustacean meal, and compost. Its full of plant nutrients, beneficial biology, organic matter, and chitin.

The best part is that it is 100% guilt free! Free your conscious of contributing to ecosystem destruction (guano and marine products), and proudly fight climate change and build healthy soil by using an insect-derived, up-cycled food-waste product like Frass by Grubbets®.



Unlike most black soldier fly, cricket, and mealworm products you’ll find, our entire process takes place in the USA. We feed our larvae a diet of FDA-approved waste streams from local retail and food  industries. This upcycling process yields nutritious Grubbets® and Frass by Grubbets® organic fertilizer. When used in place of conventional fertilizers, not only are you feeding your plants and soil, but you are also helping create a more sustainable planet.

We are striving to repair the planet for future generations. We do this by using the power of nature to fully integrate US food waste into the circular economy.


Ditching synthetic fertilizers for Frass by Grubbets® is an easy way to reduce your carbon footprint and fight climate change!

Manufacturing synthetic nitrogen fertilizers is an extremely energy-intensive process. In 2018 the supply chain was responsible for estimated emissions of 1,350 million tons of CO2e. That is roughly 21.5% of the annual direct emissions from agriculture.



To make matters worse, these synthetic fertilizers pollute our waters with nutrients and contribute to the degradation of our soils. Nutrient run-off from water soluble nutrients makes its way into our rivers, streams, lakes, and oceans. This ultimately causes serious damage to aquatic ecosystems, people, and pets from algae blooms, as well as a loss of aquatic animal life due to lack of dissolved oxygen in the water.



Organic matter content is one of the key indicators of soil health and the use of synthetic fertilizers causes a loss in soil organic matter. It is a common misconception that synthetic fertilizers kill soil bacteria which ultimately causes the loss in soil organic matter, however that is not accurate. Both plants and soil microbes utilize organic matter throughout the season. If you are only adding synthetic fertilizers, you are not replenishing that vital organic matter, causing it to become depleted.

Another problem with synthetic fertilizers is their salt content. Overtime salt levels from synthetic fertilizers accumulate in the soil decreasing its fertility and ability to support plant and microbial life.

For more information, check out this article by the Institute for Agricultural and Trade Policy.


We make being a part of the solution easy! Rebuild soil health and fight climate change by returning nutrients, organic matter, and carbon to the soil with Frass by Grubbets®.

Healthy soil is more than just “dirt”. It is a living ecosystem that provides us with upwards of 17 trillion dollars in “eco-system services” each year. One of these important ecosystem services is carbon sequestration in the form of organic matter. The use of synthetic fertilizers causes our soils to lose organic matter, causing a serious decline in their health, fertility, and carbon storing capacity. Investing in our soils by rebuilding levels of soil organic matter is a crucial aspect in combating our changing climate.



What does soil do for us?

  1. Provides us with food.
  2. Stores and filters water.
  3. Recycles nutrients.
  4. Sequesters carbon.
  5. Regulates temperatures.
  6. Flood protection.

Learn more about the importance of soil health from the USDA National Resource Conservation Service!