Vermicomposting

Vermicomposting is the processing of organic wastes through earthworms. It is a natural, odourless, aerobic process, much different from traditional composting. Earthworms ingest waste then excrete casts – dark, odourless, nutrient and organically rich, soil mud granules that make an excellent soil conditioner. Earthworm casts are a ready-to-use fertilizer that can be used at a higher rate of application than compost, since nutrients are released at rates suitable for growing plants.

Vermicomposting can be done on a large scale by farmers with manure or using organic wastes such as fruit and vegetable cull materials. Through proper design, it provides a method of waste handling that:

  • is clean, socially acceptable, with little to no odour
  • reduces waste to landfill
  • requires no energy input for aeration
  • reduces the mass of waste by 30%
  • produces a valuable vermicast by-product

The Fruit Farm currently produces field scale vegetables and fruit from approximately 16 acres. The farm is farmed to organic standards, although not currently certified. A significant amount of vegetable waste is produced throughout the year and thought is currently being given to how best manage this waste in the context of organic farming.

The aim of this project is to assess the suitability of vermicomposting vegetable and fruit waste produced on the holding to provide an organic manure which can be returned to the land to meet the nutritional requirements of the crops.

 

What will be done:

A vermicomposting system will be constructed to compost the waste produced on the farm. The composting time frame is expected to be around 28 days, and the resulting compost produced will be analysed for its nutritional value. This compost will be compared with a control of a conventional compost heap set up according to best practice.

The wormery will be constructed from 4 wooden potato storage boxes which are approximately 1.2x1.8x0.8m high. The bottom of the boxes will be covered with a permeable polypropylene membrane and covered with sand and gravel. The bins will also be covered with permeable polypropylene membrane. Holes will be drilled in the sides of the boxes to enable the worms to move from one box to the next. In this way worms can move from a composted waste bin to an adjacent bin with waste ready for compost.

A Nutrient Management Plan will also be done for the holding, strategically soil sampling all the growing area, and guidelines will be given for the resulting tested vermicompost application rates according to the vegetables or fruit grown. With the move to organic production, the resulting compost will be the main nutrient supply