The Basics About Compost

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Defining compost

Compost in its simplest form is a recycling process where organic matter such as wood, vegetable scraps and leaves which is regarded as waste, is decomposed and turned into a product rich in nutrients that feeds the soil. Compost is the product created through a natural process where organic (waste) products are combined so that micro-organisms can develop and decompose these materials into a useable product called compost. By combining carbon, nitrogen, oxygen and water in the correct amounts the perfect environment is created for micro-organisms to appear naturally and to thrive. This will speed up the composting process significantly as long as the environment is closely monitored and controlled. The above-mentioned process of adding carbon, nitrogen, oxygen and water is also referred to as hot composting.

A neatly stacked compost heap turned weekly with a TOMCAT WN3000 Compost Turner
Weekly inspection is the key to making great compost

The four key ingredients for the perfect compost

  • Browns (Carbon) – High carbon material is usually dry and brown in color. This includes leaves, small twigs, wood chips, straw, hay shredded newspaper, cardboard and coffee filters. Heat is generated when the microbes break down the carbon.
  • Greens (Nitrogen) – Nitrogen is needed to develop microorganisms to break down the carbon. These materials are usually moist and colorful such as vegetables, grass clippings, fruit waste, coffee grounds and tea bags.
  • Air (Oxygen) – The microbes need oxygen, otherwise they die and the process slows down. Oxygen can be supplied by turning the entire heap once or twice a week. Turning the heap controls the odour and gets the material that was on the inside to the outside and vice-versa.
  • Water – Compost needs between 40% and 60% water to break down effectively. If the compost is squeezed in your and hand the water drips out it is too wet. Too much water will cause it to not break down as the water will fill the spaces where air is supposed to be.

What not to add to your compost

  • Dairy products (milk, butter, yogurt and eggs), meat products, fats and grease should be avoided as they give off a bad smell and attract rodents and flies.
  • Plants that died from pests should not be added as they could be carried on and end up back in your ground.
  • Weeds or plants that have been sprayed with herbicide or pesticide may harm the beneficial micro-organisms you want inside the compost.
  • Animal or human faeces can contain harmful germs, bacteria and viruses.

Most popular uses for compost

Compost is rich in nutrients and can act as a natural pesticide for soil which makes it useful and beneficial in the following applications:

  • Organic farming
  • Agricultural sector (fruit & vegetable farming)
  • Gardens and flower beds
  • Cow bedding
  • Landscaping
  • Land and river reclamation
  • Mulching
  • Erosion control

Benefits of compost

  • Compost is full of nutrients which enrich your soil and increase the fertility of your trees and plants.
  • It helps to reduce plant diseases and repel pests.
  • Compost retains moisture and helps reduce water runoff.
  • Reduces your carbon footprint as you recycle material that would have ended up on a landfill.
  • Saves you money by reducing your bill on buying soil conditioners at a store.
Compost heaps are built far apart and on a flat surface

How to start

  • Choose a flat clean area where you want to build your compost heap. Make sure that your heaps are not too close to each other and that there is plenty of space for your compost turner to turn at the end of the heaps. Also keep in mind that your row shifts with a couple of meters up or down every time you turn the compost so leave enough space at the end of your rows. If you want to make compost at your house you can enclose the compost area with bricks, wood or plastic to make it more aesthetically appealing.
  • Make sure you have enough browns (carbon) and greens (nitrogen) to make a 1 meter high pile. Begin by mixing 1 part greens and 3 parts browns. If the mixture is too moist and it smells, you can add more carbon to increase the airflow and reduce the moisture content. If it is too dry you can mix some nitrogen (wet items) and water.
  • Your compost mixture should feel like squeezing a wet sponge. Too much water will kill the micro-organisms and cause your compost to rot instead of decomposing. Should you have a scratch or wound on your hand, avoid touching or squeezing the compost with your bare hands as you might contract bacteria that can cause severe illness. Check it every week with a thermometer. If the temperature exceeds 70 degrees Celsius it will kill the beneficial microbes inside your compost.
  • Turning your compost is an extremely important part of the composting process. You cannot complete the entire composting process if the material is not turned once or twice a week. It exposes the compost to oxygen which in turn stimulates micro-organisms which is required to properly break down coarse material. When you turn compost it must be done quickly, efficiently and frequently. It also allows the microbial activity to reach all the material effectively. Closely monitor your compost to determine the ideal turning intervals. The temperature of the compost is measured using a thermometer. The ideal temperature is between 55 and 60 degrees, where after it should be turned. It should not exceed 65/70 degrees Celsius. In the beginning of the process the compost needs to be turned more frequently to mix the compost properly and to activate the process. Turning your compost also helps to drain away water and allows air to enter between the material.

How to determine whether your compost is ready

Compost usually takes 6 to 16 weeks from start to a finished product. The following indicates that your compost is ready to use:

  • When the temperature of your compost goes down and it no longer gives off heat
  • It gets a brownish colour and is crumbly between your fingers
  • It feels dry

Why use a TOMCAT Compost Turner?

The TOMCAT PTO-driven WN1600 & WN3000 compost turning units are built to work through compost heaps efficiently and economically. The WN1600 is for 1.6m rows and the WN3000 is for 3.0m rows. These machines are strongly built with simplicity, which makes it easy to use and to maintain. They have been designed to produce microbially-active, high quality compost.

Tractors with a crawler gear with speeds between 250-750 meters per hour are a must, for these machines to operate efficiently.

A special hardened steel is used to manufacture the blades to ensure long lifespan and reduce running/maintenance costs. Each blade is uniquely shaped to bring the compost from the bottom to the top and from the outside to the inside. This allows the compost rows to have a chimney effect to create the perfect flow for CO2/Oxygen. Adding moisture to your compost will increase the microbial activity and is an essential part of compost making. A nozzle watering system is built in (fittings not included) to provide the perfect amount of moisture to your compost. It requires little maintenance and repairs are easy to do when breakages occur.

Unique Features:

  • These compost turners have a transport mode.
  • The unit is quickly converted from operational mode to transport mode with the use of hydraulics.
  • Because of this feature it is easy to maintain, especially when you have breakdowns while in operation, as it cuts into a heap or turns quickly out of it.
A TOMCAT WN3000 Compost Turner busy turning compost thoroughly, effectively and efficiently