Circular Economy Capacity Building in the Horticulture Industry – Module 2

Welcome to the second module of the Circular Economy Capacity Building Program!

This week we’re diving deeper into understanding the circular economy, and it’s all to do with butterflies. Watch the video first and then have a read about this very helpful tool for understanding materials management in a circular economy: the Butterfly Diagram.

Materials Circulation Framework: A guide to “what good looks like” for materials management

When we extract resources from nature, whether through mining or agriculture & horticulture, we transform them into the products and materials that fuel our societies and economies. Once these products enter our economy, it’s essential to understand how they should be managed & circulated to retain their value. That is the purpose of the Butterfly Diagram, a guiding tool for how to circulate materials at their highest value for as long as possible. 

Of course the most effective material management strategy is to rethink if we need the material at all, but if we do decide to bring a material into circulation, the Butterfly Diagram is our guide! 

The Butterfly Diagram (Figure 1) separates materials into two main types: technical materials (like plastic, steel, and electronics) and biological materials (like plants, timber, food, and textiles). Each type follows its own pathway in the circular economy. 

Technical Materials 

Let’s begin with technical materials, the right side of the Butterfly Diagram. These materials are finite, which means we cannot grow more once they are extracted. Therefore, in a circular economy the focus is on keeping them in use for as long as possible, through one of nine technical materials circulation strategies, with maintenance & reuse as a priority and recycling & waste–to–energy as a last resort in the technical circulation hierarchy. 

For the nursery industry, reusable plant pots can be returned by customers, sterilised, and reused to grow new plants, reducing the need for new pots. In the case of repairing, an example could be the damaged drip irrigation lines that can be repaired by patching or replacing sections rather than purchasing an entirely new system. Finally, if no longer reusable due to degradation, plastic pots could be remanufactured by partnering with plant pot suppliers to directly turn old plant pots into new ones. Unusable pots could be collected from nurseries, cleaned and melted down into new pots or trays for continued direct use in the nursery (rather than being recycled into products we don’t need, or evading capture & ending up as pollution in the system). 

Biological Materials: Regenerate and Cascade 

Now, let’s look at biological materials, the left side of the Butterfly Diagram. These materials come from renewable resources, which means they can regenerate naturally. However, it’s important to remember that we must not extract these faster than the natural regeneration rate of the Earth, lest we exhaust the Earth’s capacity to produce and provide life-giving services. As such, we should extend their use by directing them through cascades. Biological materials, such as plants, timber, food, or natural fibre textiles, can safely re-enter the natural cycle. These materials decompose without harm and can return to the earth as compost or nutrients, supporting ecosystem regeneration.

Biological materials are particularly relevant to the horticulture industry, tying in with the industry’s inherent values of regeneration & care for land, and many practices that are already inherent to the industry, such as composting.  

Given horticulture’s relative maturity in biological materials circulation, the industry has an opportunity to have an outsized impact on how these materials circulate in our economy. The industry’s expertise and experience in natural cycling of materials indicates that it is in a prime position to influence actors around it: suppliers; customers; and local communities. For some of us, this may even represent an opportunity for diversification into new offerings that can expand our market segments.  

For example, Cirque du Soil, a Melbourne-based organisation connecting materials throughout the community, is offering multiple, innovative services that are leveraging their expertise in biological materials & natural cycles. They are now partnering with Moonee Valley City Council to offer an Organics Advisory Service to local businesses as a part of Council’s Let’s Go Zero program. They are also starting a Compost Shop, leveraging their Community Waste collectives to aggregate and sell compost material in a centralised location.

Bridging Biological and Technical Cycles: Enablers of material circulation 

The Butterfly Diagram helps us to understand how materials should be circulated, but there are other factors, such as new, circular design techniques & commercial models, that will create the enabling conditions for both biological & technical materials circulation.  

After all, many changes will need to be made for a true circular economy- an important reminder that a circular transition cannot be achieved without collaboration; between our own industry, with our suppliers, our customers, and our local communities.

We’ll be covering these enabling tools in our upcoming modules. Please don’t hesitate to reach out in the meantime!