What Is Frass and Why Is It Gaining Attention?

Frass is simply insect manure. While that might not sound exciting at first, it is quickly becoming one of the most interesting and useful by-products of insect farming.

As more people become aware of soil health issues, sustainable food systems, and the limits of synthetic fertilisers, frass is attracting attention as a natural and effective way to support healthy plant growth. It fits well with modern approaches such as organic gardening, small-scale horticulture, and regenerative agriculture.

Why Soil Health Matters

Many modern farming methods focus on short-term crop yields, often at the expense of long-term soil health. Over time, intensive farming can cause problems such as:

• Poor soil structure and reduced water retention

• Loss of beneficial microbes and organic matter

• Nutrient imbalances caused by repeated use of synthetic fertilisers

• Reduced biodiversity in the soil, which affects plant health and resilience
  

When soil biology is damaged, plants become more dependent on artificial inputs and less able to access nutrients naturally.

How Frass Helps

Frass works differently from conventional fertilisers. Rather than delivering a fast nutrient hit, it supports the soil itself.

When added to soil or potting mixes, frass can:

• Improve soil structure and help soil hold moisture

• Feed beneficial microbes that make nutrients available to plants

• Release nutrients slowly over time

• Support stronger root development and overall plant growth

• Help plants better cope with stress, pests, and disease
  

Because of this, frass is often described as both a soil conditioner and a biostimulant, rather than just a fertiliser.

What Nutrients Does Frass Contain?

Frass naturally contains a range of nutrients that plants need, including:

• Nitrogen – supports leafy growth

• Phosphorus – helps roots develop

• Potassium – improves plant strength and resilience

• Calcium and magnesium – important for plant structure and photosynthesis

• Trace elements such as iron, zinc, and manganese
  

The exact nutrient levels can vary depending on what the insects were fed. In simple terms, better feed results in better-quality frass.

How Is Frass Used?

Frass is most commonly mixed into soil or growing media, where microbes slowly break it down into plant-available nutrients. It is also sometimes used as part of a broader fertiliser blend rather than on its own.

Because nutrient levels can vary, testing is recommended where possible, especially for commercial use. Like any soil input, frass may not be suitable for all plants or situations without adjustment.

A Natural Fit for Sustainable Growing

Frass offers a practical way to improve soil health while reducing reliance on synthetic fertilisers. It supports natural nutrient cycles, encourages healthy soil biology, and aligns well with sustainable and circular growing systems.

For growers looking to build healthier soil—not just faster growth—frass is well worth learning about.