Case study

Elliott’s Nursery achieves optimal AFP by blending Azwood’s aged bark fines in their potting mix

Elliott’s Nursery manufactures their own potting mix using their repurposed green waste and Azwood’s aged bark fines. This reduces shrinkage and provides optimal air-filled porosity.

Customer since
2014
Product used
Aged bark fines

Overview

Azwood supplies Elliott’s Nursery with aged bark fines to blend their green waste and other nutritional elements to create potting mixes used on-site to grow plants.

This elimination of waste creates a circular economy from a resource that would otherwise be left unutilised.

Background

Elliott’s Nursery has been operating since 1980. Spread over twenty-five acres, the Amberley site hosts tunnel and shade houses, potting sheds, media preparation spaces, open-ground growing sites, and production rows.

The nursery industry, like many others, has wastage issues from dead plants, trimmings and leaf debris. To reduce this, Elliotts Nursery collects their waste, screens it and blends it into their potting mix recipe (about 10-15%).

They then use Azwood’s aged bark fines to blend into their potting mix. Unlike fresh bark fines, aged bark fines are more chemically and physically stable, therefore, creating ample space for drainage and aeration.

Sometimes the bark we previously got was more wood than bark. The problem with wood is that it decomposes into nothing and then the mix shrinks. As it decomposes it loses its AFP. Azwood’s bark fines come to us aged so we don’t lose AFP, which is exactly what we need.

Jeff

Elliotts Nursery

Challenges

Elliotts Nursery's previous bark fines were delivered fresh. And although in most circumstances, fresh might be good, in the case of bark fines for potting mix it is better to have them aged.

The bark fines they were getting also had too much wood which shrunk as it aged and affected the AFP.

Assessment

When it comes to potting mix, AFP is essential to ensure that the plant roots receive adequate oxygen, water, and nutrients to grow and thrive.

Why is aged better?

Due to bark fines being a natural product, it shrinks and compacts as it starts going through decomposition. If you get fresh bark fines, over time it will shrink and therefore there is less product once it's gone through the composting process. If you get aged potting mix it has already shrunk and consequently, you don't lose product.

Why is AFP so important for potting mix?

AFP stands for Air-Filled Porosity, which is the percentage of air spaces in a potting mix.

The availability of oxygen in the soil affects the absorption of nutrients and water by the roots. Therefore, the AFP of a potting mix should be optimal to maintain a healthy growing environment for plants.

Outcome

Elliott's Nursery made the switch to Azwood’s bark fines as they found the quality to be much more consistent and the ratio of bark to wood a lot higher, which reduced shrinkage and increased the nutrients available.