A biodegradable mulch that is environmentally friendly and cheaper to use by fruit and vegetable growers is being trialed by the Department of Primary Industries as part of a review of plastic mulch alternatives.
DPI senior horticulturist, Mr Ross Wright, Bowen, said the mulch trials would include the use of biodegradable mulch that was based on cornstarch with a biodegradable polymer additive.
“The new mulch was developed in part to address issues of disposal of traditional plastic mulch in many horticultural communities across Queensland,” he said.
The concept of biodegradable mulch was initially investigated in 1999, but polymer costs meant that commercial use of the mulch at that time was too expensive.
Mr Wright said polymer costs has fallen, making it more competitive with conventional plastic mulches and potentially providing a solution to disposal problems of traditional plastic mulches.
“Currently black plastic mulch needs to be collected by an official plastic recycler, or disposed of at a licensed landfill.
“Both of these disposal options incur costs, which contribute to reducing the bottom line for growers. Burning of the waste mulch by some growers is also known to occur. This practice not only produces toxic fumes, but is illegal and offenders can face penalties and possible prosecution,” Mr Wright said.
The project is being undertaken at the DPI’s Centre for Dry Tropics Agriculture in Bowen, in partnership with Plantic Technologies Australia Ltd., with matching funds from Horticulture Australia Limited.
The feasibility of similar mulches developed in earlier trials and the suitability of biodegradable mulches from other sources will also be reviewed.
“The initial stages of the trial will review the suitability of the biodegradable mulch to local conditions.
“A crop will then be introduced to enable us to come up with mulches that are suitable for further commercial trials,” he said.
The biodegradable mulches that make the short-list will be then taken on-farm to assess their commercial performance across a range of fruit and vegetable crops and soil types.
In the meantime, growers have been reminded to dispose of black plastic mulch in the approved manner.