Making compost in a windrow is hot composting on a larger scale and not normally the domain of domestic compost makers, therefore when considering how to make compost at home a windrow is unlikely to be your first choice. A composting windrow is a long row of material with raw compostable ingredients at one end and finished compost at the other. Similar to using a compost pile or compost heap, composting in a windrow is a very simple business, you gather together the ingredients and turn them on a regular basis. However you are processing much larger volumes of material and will have a regular volume supply therefore space is a critical factor. Making compost using a windrow is usually the domain of commercial businesses, public green waste processors or the goundspeople of large estates.
To sucessfully produce hot compost using a windrow you will need;
- Plenty of space for;
- storing your raw materials prior mixing them and adding them to the row
- your windrow, or windrows, which will be as long or as short as required for the volume of materials you need to process
- processing the finished compost
- storing the finished compost.
- A mechanism for turning the compost. A garden fork may be enough for a 3 meter windrow however much larger than that and you are going to need to look for help with either additional labour or mechanical assistance.
- Pleanty of waste fruit, vegetable and plant matter. These are nitrogen producers, also known as "greens" which contain water.
- pleanty of waste paper, card and woody matter. These are carbon producers, also known as "browns", which absorb water.
- Air. Compost production is and aerobic process. The microorganisms, bugs and beasties manufacturing your compost for you need to breathe.
- Time. Managing a windrow is a daily process.
You may also need to consider;
- an industrial sized compost seiving machine
- shredding machines
- a method to collect and dispose of the leachate, commercial windrows are often processed on concrete
- fire control equipment
- How you can use or sell on any excess compost manufactured
- any other ingredients available to you.
Using a windrow is the composters equivalent to a conveyor belt. The space allocated to compost making needs to be broken into 3 sections, the raw materials input section, the composting section and the compost output section, your materials will move from one end to the other just like on a conveyor belt. When considering how to make compost in a windrow you need to think about the volume of material available to you throughout the year as material supplies will vary, more in spring and summer and less in winter, so the size and number of windrows will change through the seasons as well, you will need to plan your space for the height of the season not just an average.
Perfect compost is created if you use a 50/50 mix of greens and browns combined equally throughout your windrow. Fine tuned mixing is not essential at the start of the windrow as by the time the materials have been turned a few times they will have sorted themselves out. When starting a row you need to start it at the unprocessed end and gradually move the materials along their allocated space until they reach the composted end. The finished compost is removed, making space, which you turn the composting materials into. The composting materials gradually move along the row as you turn, eventually creating space at the "raw" end for you to add more material.
Regular turning keeps air in your mixture, which in turn allows the microorganisms to breathe and keep composting. Due to the volume of materials being processed and the regularity of turning you will not need to add a compost starter. You will need to monitor the temperature, especially if you plan to add, or there is a risk of any food waste becoming incorporated into the mix. It is not unusual for extreme temperatures to be reached inside a compost heap and yes there is a risk of fire so keep an eye and a bucket of water or hose handy.
The hot composting process will still take between 6 - 8 weeks and the compost in the windrows will mature quite nicely if you need to store it there before you grade and send it out for use.
If you have any questions about composting in windrows please ask me.