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There is nothing worse than looking around your garden and seeing your plants or crops looking unhealthy. Then you begin assessing the pathogens, ph level, and which nutrients are deficient. Most of the time, people add chemical fertilizers to their gardens to increase nutrient availability.

Chemicals are not really the best option, and compostcan vary. If you are wondering whether you should go the organic material route, many questions may arise. There are also many organic fertilizers in the market to compare to. The most used ones are the insect frass and worm castings. So, which one should you be using?

Insect Frass vs. Worm Castings

Worm castings are our choice in this comparison. Although they both are great options, you cannot deny the added benefits of worm castings.

  • They are cheaper
  • You know that they are organic because you know what they have been feeding on and there are no trace chemicals present
  • They provide better soil aeration
  • Provide a neutral ph level
  • Contain plant growth hormones essential for growth

To explain how we got to this conclusion, let us take a closer look at both options. 

Insect Frass

Insect frass is insect poop. It contains digested plant material that an insect has excreted. The waste can sometimes contain bits of insect exoskeletons, especially in powder form. It contributes to its high chitin levels. Chitin triggers a plant's immune system, which makes a plant resistant to pests and pathogens.

Mealworm frass, black soldier fly frass, and cricket frass are most commonly available for gardens and crops; also, insect feces can come from any insect. Moreover, it comes in both liquid and powder form. Insect frass can be applied as a foliar spray, a top dress to soils, or incorporated into the ground with compost. We recommend a once-week application. However, reapplication depends on the condition of your plants. 

Benefits of Insect Frass as a Fertilizer

Insect excreta has a high chitin content, which triggers a defense response in plants. It makes a plant resistant but not immune to insect attacks. Insect feces contains valuable macro and micro nutrients that promote plant growth. Additionally, it contains nitrogen, phosphorus, and potassium. Moreover, whether liquid or powder, these are essential nutrients to make your plants healthy.

Insects are bred solely for frass production, and it is considered organic. The energy requirements and carbon footprint of frass production are much lower than any manure. Lastly, insect frass has a high microbial content. Furthermore, these microbes contribute to soil health and are highly beneficial to the plant.

Disadvantages of Insect Frass as a Fertilizer

Insect frass is relatively expensive. Depending on the insect used, collecting insect poop can be difficult. In addition, this is because it is not produced in large amounts by insects. It also depends on what the insects feed on. It is why most of the time, people purchase insect frass instead of producing or collecting their own. Suppliers of insect frass breed insects for the sole purpose of frass collection. 

The quality of the insect frass can vary, and it is mainly dependent on the plant that it has eaten. Thus, unless you are sure of the host plant properties, you may still have to use other forms of fertilizer with the frass. Insect poop is tiny, and as much as it releases nitrogen, potassium, and phosphorus slowly into the soil, it does not provide much aeration. 

In addition, if the frass quality is poor, it may actually harm your plants more than help them. Hence, it is essential to know what the insects have eaten. In addition, if the insects were fed on an artificial diet and not plants, then it is not better than using chemical fertilizers. Plus, the additives and chemicals used will be present in the frass. 

Worm Castings

There are many reasons why the presence of earthworms indicates good soil health. One of them being the production of earthworm castings. Worm castings are the waste produced by earthworms. Moreover, earthworm castings provide organic matter rich in nitrogen, potassium, and phosphorus. It also provides soil aeration, which is important for plant growth and soil moisture. In addition, worm castings have plant growth hormones that promote root growth. 

Worm castings are sold in their natural state, but you can use them in liquid form for foliar application and in a hydroponic system. They are mainly incorporated into the soil but can serve as a top dressing.

Benefits of Worm Castings as a Fertilizer

Worm castings are easy to produce and harvest. Furthermore, they are cheaper as compared to insect frass. The form and structure of worm castings promote excellent aeration in the soil. Plus, it encourages root growth and expansion and helps with soil moisture levels. Both aeration and soil moisture is critical for plant growth.

Due to the digestive processes of earthworms, worm castings contain growth hormones, and it also contributes to rapid root development. The nutrient and microbial contents of worm castings have many benefits. Moreover, they work together to ensure that your soil health is optimal for plant growth. The best part is, you do not even have to use a large quantity in your soil to see the positive effects.

Disadvantages of Worm Castings as a Fertilizer

Producing worm castings yourself using vegetable matter is time-consuming. As much as it is challenging to produce worm castings, the amount needed to fertilize your garden may take some time. Also, worm castings are not suitable for plants that prefer acidic soils.


When it comes to insect frass vs. worm castings, worm feces are the more suitable and beneficial choice. No matter where you want to use it, worm castings like Simple Grow provide the most benefits for soils. Combining this with the fact that it is easier to produce and, therefore, cheaper, it is the best choice out of the two. 

In addition, if you consider buying worm manure as fertilizer, make sure that the earthworm's diet is organic, pesticide and GMO-free. It leads to high-quality, affordable worm castings for your plant growth needs. Thus, if anyone asks you about fertilizer, compost, insect frass, and worms castings, you now know which one is better.  

Grow Bigger Plants with Simple Grow

Do you wish your plants would grow bigger? Was your garden less than it should've been last year?

If you're tired of growing puny vegetables and fruits, it's time for an upgrade...Simple Grow Worm Castings!

What are worm castings? Another term for worm manure. Why would you want to use it in your garden, raised beds, and house plants? Because it makes them grow bigger, faster and healthier...with no chemicals!

How do worm castings do this? It's like giving your plants a powerful multivitamin with everything they need to grow. Trace minerals, nutrients, and most importantly...worm castings are chock full of beneficial microbes. Why does that make a difference?

In recent years, we've learned the importance of gut bacteria for humans and know that it impacts so many different parts of our health. The same thing applies with worms. Gut bacteria from the worm's digestive tract gets into the soil from the worm castings and promotes plant health. Plants have a symbiotic relationship with the microbes from the worm's digestive tract. Plants respond to it and grow really big...really fast!

If you've never tried worm castings before, you owe it to yourself to give them a try. Instead of using traditional chemical fertilizers from the big box store, why not try fresh, certified organic worm castings this year? You'll be able to grow bigger, healthier plants that you actually can feel good about eating. 

Take advantage of our special bundle sale on 25lb bags today!


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