'Next-generation' compost is a generic term used to describe commercial compost products that are amended with a nutrient source, primarily to compensate for nitrogen immobilisation. In recent years, progressive recycling firms have been developing methods for generating ‘next generation’ composts made from urban organic waste that are suitable for use in food production.
These composts can be used not only to replace some fertilisers but to improve soil and crop health, reduce nutrient leaching and increase water-use efficiency.
Switching to a compost-based fertiliser regime can transform your vegetable farm by improving soil health, reducing chemical costs, and protecting crops from stress.
Achieving these great results, however, depends on sourcing the right compost product and applying it correctly.
Above all, it is critical to source compost from a supplier who is committed to and capable of providing a true agricultural compost. Many farmers have had bad experiences with compost made from recycled organics because they have spread immature or contaminated product.
Be prepared to pay more for a product that is tailored to the needs of your soil and crops and that meets the Australian Standard for compost for use in food production: AS4454-20-12 Composts, soil conditioners and mulches.
Key practices for achieving success with next-generation composts
The tips that follow relate to practices the Next Gen Compost project has identified as being essential to achieving success with compost you have not made yourself. They have been derived from comparative trials undertaken for the project; review of previous commercial compost trials; and reports from growers about their experiences, good and bad, with compost supplied by recyclers.
It's crucial that you get independent agronomic advice about:
- the health of your soil and how best to remediate it;
- developing a staged plan for increasing organic matter and natural fertility using compost that covers spreading rates and frequency of applications; and
- the exact specification of compost required by your soil and your crops.
Analyse your cost structure with a view to replacing some chemical fertiliser with next-generation compost. This analysis may factor in longer-term savings resulting from improved crop and soil health and soil water-holding capacity.
Find a compost supplier who can provide compost to your specification and at a viable price point.
Don't purchase or receive any compost without understanding exactly what you are getting.
Do not allow a load of compost to be tipped unless you have received a declaration from the supplier that the compost meets the Australian Standard, and have physically inspected the load for contamination.
Do not purchase or spread compost that does not comply with the Australian Standard.
Using immature compost may set back your crop and could even kill it.
As noted above, augmentation should be done to your specification on the basis of independent agronomic advice. If a supplier will not provide a report on delivery that attests to the specification of the load do not use that supplier.
The Australian Standard
The quality of commercial compost made from organic waste is covered by Australian Standard AS4454-20 -12 Composts, soil conditioners and mulches. The Standard sets up chemical, physical and biological requirements for human, plant, animal and environmental safety. This ensures the material is safe to use and is of a consistent quality, free from heavy metals and not contaminated by plant or animal pathogens or plant propagules.
From a farmer’s point of view, using a compost that complies with the Australian Standard provides peace of mind. This is because the Standard encourages manufacturers to police the raw materials used to make these products.
Finding a suitable supplier
Recyclers have different business models; not all of them are set up to provide agricultural composts. Compost that is excellent for landscape gardening and/or broadacre soil rehabilitation is unlikely to be suitable for vegetable farming. The Australian Organics Recycling Association can help you to find a compost supplier who understands the needs of commercial vegetable production and can meet your specifications.
Where can I find out more?
This factsheet is one in a series developed by AgInnovators as part of the Next Gen Compost project. The project field trials and other activites are still in progress. Subscribe to AgInnovators for news about further results, guidance, and notifications of upcoming field days.
About the Next Gen Compost project
Next Gen Compost is a two-year project commenced in 2016 that aims to help increase the use of compost made from recycled organic waste in commercial vegetable production. It is led by Greater Sydney Local Land Services (LLS) in partnership with NSW Farmers and the Institute for Sustainable Futures (UTS). The project is funded by the NSW Environment Protection Authority (EPA) under its Waste Less, Recycle More Organics Market Development Grant Program.