15/10/2026
🪱🌱 CAN WORM-BASED PRODUCTS INFLUENCE HOW PLANTS RESPOND TO APHIDS? SCIENCE HAS SOMETHING INTERESTING TO SAY! 🔬
Sometimes the most interesting discoveries begin with a simple conversation.
Recently, we had an almond grower visit Riverland Backyard Worms to purchase worm juice and worm castings.
During our conversation, he shared something that caught our attention.
He had previously used a liquid worm-derived product from another producer on his almond trees and noticed that his aphid problem appeared to disappear afterwards.
Naturally, that got us curious!
Was it a coincidence? Did something else change in the orchard? Or could there be some scientific research behind what he observed?
So we started looking.
🔬 WHAT DID WE DISCOVER?
We found a peer-reviewed scientific study published in 2010 in the international journal Crop Protection.
Researchers, including Clive Edwards and Norman Arancon, investigated whether liquid extracts made from worm castings, also known as vermicompost, could influence pest populations on tomato and cucumber plants.
In this context, a vermicompost extract was a liquid prepared by extracting soluble material from vermicompost. It should not automatically be treated as the same product as worm juice, which can refer to different liquids collected or produced during worm farming.
The researchers compared plants receiving vermicompost extracts through the growing medium against plants receiving water alone.
Their findings were fascinating.
🌱 Plants receiving the vermicompost extracts had significantly lower green peach aphid populations and reproduction.
🌱 The researchers also observed reduced populations or damage involving citrus mealybugs and two-spotted spider mites.
🌱 Higher extract concentrations generally produced stronger effects in these experiments.
The researchers suggested that soluble compounds from vermicompost, potentially absorbed by plants, could help explain the results.
Importantly, these were controlled greenhouse experiments using vermicompost extracts applied to the growing medium — not commercial trials spraying worm juice onto almond trees.
📚 WHAT DOES PEER-REVIEWED ACTUALLY MEAN?
You might hear the words peer-reviewed research quite often.
Put simply, it means that before a scientific study is published, other researchers with expertise in that field examine its methods, evidence and conclusions.
They assess whether the research has been conducted appropriately and whether the conclusions are supported by the results.
It doesn't mean every finding is guaranteed to be correct, but it provides a stronger scientific foundation than an opinion, advertisement or individual observation.
🌏 WHY IS THIS INTERESTING FOR THE ENTIRE WORM-FARMING INDUSTRY?
This isn't just about Riverland Backyard Worms.
It's about the wider potential of vermiculture and the different products that worm farmers produce.
Worm castings are the solid material produced through vermicomposting. Vermicompost is often used to describe the finished material, while a vermicompost extract is a liquid made by extracting soluble components from that material. Worm juice is a less standardised term and may refer to liquid collected from a worm farm or another worm-derived liquid product. Vermicompost tea is also a separate term that commonly refers to vermicompost steeped or brewed in water, sometimes with additional inputs.
These products are not automatically interchangeable, and their composition can vary with feedstocks, worm-farming methods, extraction or brewing processes, storage and application methods.
Across Australia and around the world, worm farmers use different production processes to create worm castings, vermicompost, worm juice and vermicompost teas.
The findings of one study on a particular vermicompost extract cannot automatically be applied to worm juice, worm castings used directly, vermicompost tea or every other worm-derived product.
But research like this gives the industry something valuable: scientific questions worth investigating further.
Could some worm-derived products influence plant responses to pests?
Could they contribute to healthier growing conditions?
And could future field trials help growers understand when, where and how these effects occur?
These are questions worth exploring together.
🤝 WORKING WITH UNIVERSITIES AND RESEARCHERS
We would like to work with universities and research institutions, whether in Australia or anywhere around the world, to hear their views on how we can contribute to further study of worm juice, vermicompost extracts, vermicompost tea and other worm-based products in relation to aphids.
We are particularly interested in understanding what researchers and authors of relevant studies would like to investigate next, and how we could support properly designed, controlled tests.
This might include helping provide clearly identified products, sharing practical information about production methods, connecting researchers with growers or assisting with field observations, where appropriate.
Any future research would need to be independently designed and scientifically controlled so that the results are reliable and useful to growers, worm farmers and the wider agricultural community.
If you are a university, researcher or study author interested in exploring these questions, we would welcome the opportunity to hear your views and discuss how Riverland Backyard Worms could be involved.
🤝 SHARING KNOWLEDGE, NOT CLAIMING A CURE
We want to be clear: this research does not prove that our worm juice, worm castings, vermicompost tea or any other product controls aphids on almond trees.
The study examined specific vermicompost extracts in controlled greenhouse experiments on tomato and cucumber plants. It did not test worm juice or vermicompost tea in almond orchards, and it does not establish an aphid-control treatment for commercial almond production.
The grower's experience is an observation, not a controlled scientific trial. Aphid populations can also change because of weather, beneficial insects and other orchard management factors.
However, it's encouraging to see scientific research investigating related questions.
At Riverland Backyard Worms, we believe the future of worm farming involves more than producing natural soil inputs.
It's also about asking questions, supporting independent testing, listening to growers and researchers, and sharing reliable information.
And when we discover something that could benefit the wider industry, we believe it's worth sharing.
📖 THE SCIENTIFIC STUDY
Edwards, C.A. and colleagues (2010)
Crop Protection, Volume 29, Issue 1, pages 80–93.
Read the research here:
https://doi.org/10.1016/j.cropro.2009.08.011
💬 WE'D LOVE TO HEAR FROM YOU!
Have you used worm castings, worm juice, vermicompost extracts or vermicompost tea and noticed differences in plant health or pest activity?
Are you a university, researcher or study author interested in controlled testing of these distinct products and aphid responses?
Whether you're a commercial grower, backyard gardener, fellow worm farmer or researcher, we'd love to hear about your observations and ideas.
The more knowledge we share, the more opportunities we create to understand what these products can — and cannot — do.
🪱 Riverland Backyard Worms – Berri, South Australia
Supporting healthier soils through vermiculture, independent testing and shared knowledge.
