Making compost from nutrient accumulating crops

Evaluation of longer term responses to compost when using nutrient accumulating crops and weeds as feedstocks

Objectives:

• Improving nutrient content of compost will lower application rates.
• Establish accumulation of soil nutrient reserves resulting from longer term use of compost (five years), resulting in a consequential lowering of application rates.
• Provide a greater percentage of organic nitrogen preferred by sugar cane.
• Identify principles for improving fungal content in cane composts.
• Compare compost costs and results between short term aerobic compost turning, (turned 15 times over 8 – 12 weeks) and aerobic static pile composting taking 6 to 8 months (turned 5 – 6 times)
• Determine that utilising high value feedstocks produce a cost effective compost

Project Activities:

-   Identify some nutrient rich plants already identified from past research, e.g. the UK Comfrey Bocking No 14 variety, (now in Australia), has a calcium content of 2% and a potash content of 15 – 20 times of cane trash.

-   Lab test these new feedstocks when composted for biology and nutrient.

-   Monitor 2 existing trial sites (established in GGP034) for a further 3 years. Soil organic matter and nutrient reserves are expected to constantly increase with annual applications consequently requiring less and less inorganic fertiliser.

-   Establish static pile composting on at least one farm in the next 2 years. Static pile composting does not require an upfront heavy capital expenditure (pay $250,000) on compost turning equipment. 

-   Establish 2 sites using these composts, monitor cane growth and analysis soil and leaf at establishment and conclusion of trial.

-   Record all field events for 3 years

Contact Person: Barbara Walker 0448 591 042