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Compost: Composting Shredder, Temperature-Moisture Gauge


Shredding, Temperature And Moisture Gauges.



Shredding dos and don’ts                                                                   
Shredding or grinding the raw materials for composting can produce several beneficial results, particularly when using leaves, woody  plants, corn stalks, and other bulky materials. Shredding or grinding organic materials makes it more susceptible to beneficial bacteria in the pile because a greater surface area is exposed and the natural defense resistance of vegetation against microbial invasion is disrupted.            Shredding the material makes it more homogenous, produces better aeration and  controls moisture. It withstands excessive drying at the surface of the pile better, and helps insulated against heat loss. The most desirable size of particles for composting is less than 2 inches, The particle size of the material being composted can be dependant on its final use. Studies have shown that piles built with particles around 1" in diameter reached 71oC-160o F, those with 2" particles reached 60oC-140oF, and those with particles 6" in diameter reached only 37oC-100oF.

A huge advantage of shredding is that it produces non- uniformed particles of varying sizes. A compost pile that has particles of only one size will not compost well because the particles tend to mat or clump together, decrease the flow of oxygen and moisture through the pile.

Shredding dos and don’ts
Don’t use freshly shredded woody material as a mulch, compost it first otherwise it may starve the underlying soil of nitrogen.

Do not try to shred paper or cardboard cartons with this unit.

Wear protective glasses and gloves - shredders occasionally chuck out bits of wood at high speed.

Do use a RCD device (which stops the power supply if it detects a short to earth)

Consider wearing ear protectors when working with a shredder.

The Ryobi RGS 1500 garden shredder
This shredder is undoubtedly the finest triple-action electric garden shredder available to date. Manufactured by Ryobi, its powerful 1600 watt motor drives four cutting discs to produce a uniformed ready-to-use mulch from leaves, twigs, small branches and general garden debris, ideal for compost preparation. Material handling is made easy and enhanced by having three different intake point.

1) Leaves & small garden clippings feed in through the top hopper.

2) Medium to large clippings are fed through the back chute of the top hopper.

3) Rear chute shreds solid branches up to 38mm diameter,

This effectively means as you shred carbon rich materials such as old wooden fence panels or branches up to 38mm in Dia. you can shred into a mix your nitrogen rich materials at the same time, the result is unquestionably the best compost mix achievable from a none commercial shredder.


  • Four disc, triple cutting action.

  • 240v powerful 1600Watt induction motor.

  • 38mm max. cutting diameter.

  • Fitted with wheels for easy maneuverability.

  • Fitted 12m cable with fitted plug.

  • Safety cut-out for operator safety.

  • Sturdy powder coated metal and plastic construction.

  • Weight 39kg.

  • Simple to strip down to maintain and clean.

  • Unique three intake points.

  • 96 Db low noise level.

  • 7 years operator experience hotline.

  • 2 years manufactures guarantee.

  • Free safety goggles, gloves and ear plugs with each purchase.

















Temperature and gauges


A few days after filling your bin check to see if your pile has heated up. Be careful, my first pile surprised me, they can and should reach temperatures upwards of 65oC, enough to leave a nasty superficial burn. For safety reasons you should use a compost thermometer and gardening gloves. If your pile does not reach 48oC degrees to 70oC you probably do not have enough nitrogen in your pile. Add more nitrogen materials, mix, and monitor again. The minimum temperature for a hot batch composting should be 46oC.
Heat is a by-product of intense microbial activity it indicates that the micro-heard of organisms are munching on organic matter and converting it into finished compost. There are primarily three types of microbes that work to digest the materials in a compost pile. They each work best in a particular temperature range:

Psychrophiles are bacteria that flourish at low temperatures. These bacteria prefer temperatures of approximately 13°C and will slowly decompose your compost even at temperatures of -17°C. As they begin to digest some of the carbon-rich materials, they give off heat, which causes the temperature in the pile to rise. When the pile warms to 15°C to 21°C, mesophilic bacteria take over.

Mesophiles are bacteria that thrive at temperatures in the 21°C to 32°C range, and can survive temperatures of 4°C to 21°C. These aerobic bacteria do most of the work of decomposition and raises the temperature inside the pile. If the mesophiles have enough carbon, nitrogen, air, and water, they work so hard that they raise the temperature in the pile to about  38°C, when the thermophiles take over.

Thermophiles are bacteria that work in the high temperature range from 37°C and 70°C. It is these bacteria that can raise the temperature high enough to sterilize the compost and kill disease-causing organisms and weed seeds. The high rate of decomposition will turn the mixture of organic materials in your pile to a uniform deep brown colour. 3-5 days with pile at temperatures of 37°C or higher is enough for the thermophiles to have done their best work.

Getting your compost pile "hot" (60oC to 70oC) is not critical, but it does mean that your compost will be finished and usable within a couple of month or so. Some people don't bother charting the temperature curve of their compost pile. They just try to get a good ratio of carbon to nitrogen, keep the pile moist and well aerated, and wait until everything looks pretty well broken down. If you want to monitor and understand what’s happening, and therefore what’s need by your compost pile, partially the core, you will need a compost thermometer or a compost aerator with a heat-sensing blade.

We have a clear sturdy compost thermometer enabling you to monitor the temperature inside your compost bin to produce perfect compost in the shortest time. Good observation of compost temperature and the remedial action taken, can speed up the composting process and dramatically reduce your physical input. To take your temperature readings, push the probe deep into the compost bin leaving the probe in place long enough for the reading to stabilize, then move it to a new location. Take readings in several locations, including at various depths from the top. Compost may have hot or cold spots depending on the moisture content and composition of ingredients. For systems like the aerobic Garden Bin Composter the hottest part of the pile tends to be 2/3 of the way up from the base.


  • 50mm or 400mm, long stainless steel easy to use pointed measuring probe.

  • 40mm easy-to-read bold markings on clear dial face.

  • Instructions indicate compost temperatures required at each stage of composting.

  • Hermetically sealed dial.

  • Range -10 to +90 degrees Celsius.

  • Accurate reading to ±1.

  • 1 years manufactures guarantee.






















Moisture and moisture meter











All life on earth, including compost microbes, need a certain amount of water and air to sustain themselves. The “Micro-heard” functions best when the compost pile has good ventilation and is about as moist as a wrung-out sponge. If the pile contains considerable amounts of strong fibrous material, such as chipped wood, the maximum moisture content can be much greater without displacing air from between the particles, destroying the structural qualities of the pile, causing the material to become soggy, compact, and unable to contain air and give rise to anaerobic conditions, limiting the composting organisms. If the material has little structural strength when wet or if granular, like a soil, it may be difficult to maintain aerobic conditions at a high moisture content. Extremes of sun or rain can adversely affect this moisture balance. Generally, the moisture content of the compost should be 50% to 60% of the total weight. Moisture content above 70% will cause the pile to leach water losing valuable nutrients, starving the available oxygen and become anaerobic, causing odour problems. If the moisture content falls much below 40%, many of the organisms will cease to function and decomposition will be slowed down or stopped.

When the composting materials are picked up in the hand and squeezed, just a few drops of water should come out. If excess water comes out, the pile is too wet and should be aerated, or dry carbon rich material added to loosen and alter the moisture % of the pile. As with temperature, your pile will have high and low spots of moisture content, tending to hold its moisture in the center while the extremes of the pile dry out. If you intend to monitor you’re moisture content without handling a potentially hot material, use a simple, low cost, soil moisture tester, push the testers probe into the pile, leaving the probe in place long enough for the reading to stabilize, in different locations. True and accrete multi-point readings will save time and water by reducing unnecessary watering of your compost. When adjusting the compost moisture content try to use captured rain water, as this contains none of the additives used to purify our drinking water capable of destroy beneficial microbes, its environmentally positive and cost effective. 


  • 5cm in width.
  • 20cm long easy to use pointed measuring probe.
  • Weights just 86g.
  • Manufacture from composite materials.
  • Measures soil and compost moisture rate.
  • No batteries required.
  • Easy to read dial indicator, scaled 1-10.
  • 1 years manufactures guarantee.



Composting is no longer the sole preserve of gardeners and horticulturist, if you have a balcony or roof garden, a small back yard with limited access. Why export garden waste or import garden soil products when you can make your soil form your waste. Are you sick of that kitchen bin, full, under the sink. Does your external bin fill up too quickly or your local authority refuse to collect green waste in the standard collection. Composting is the answer to these, and many more problems. Imagine no food scrapings in the kitchen bin, imagine no overflowing, rodent attracting external bins. Just imagine the kids taking part in keeping the rubbish bins manageable, what! Well this is the young urban face of composting, a practical, useful and cost effective enjoyable waste solution, that’s the key and its so simple. So lets look at the urban waste you can successfully compost.

Our homes generate plenty of waste paper from children's homework to incoming junk mail, the daily newspaper to packaging waste. Add a home office and the paper pile grows deeper and deeper. In recent years a more sinister reason for shredding your paper waste has arisen, that of home security. It is estimated that in the UK alone more than 100,000 people are affected by identity theft each year, costing the British economy over £1.3 billion annually. So if your in the habit of separating out and shredding for security peace of mind, its not a large step to separate and prepare paper waste for composting, the ultimate in document destruction.   

What kind of paper and card can be composted?
Large amounts of newspaper and cardboard should enter the well developed recycling markets along with Glossy, shinny magazines. There’s lots of other paper and card around the house that normally ends up in your waste system and could be composted. These include office, computer paper, old envelopes (remove the plastic window and sticky strips first), ripped up cereal packets, toilet roll cylinders, cardboard egg boxes, tissue paper and most packaging, the list is endless, for instance at home I religiously compost anything to do with my undesirable habit of smoking from the finished cigarettes and ash to the cigarette packets minus their foil inners, its all from an organic source. Avoid frozen food packaging and cartons used to hold liquids, as these are often bi-material, lined with a thin film of plastic or foil. These urban waste need to be shredded to accelerate their decomposition and avoid clumping together, restricting ventilation of the pile. Presoaking paper and card products in a bucket of water, left outside, which is then used to moderate the compost moisture content is an excellent but excessive preparation, you soon discover which product type breaks down the quickest and is best receptive to composting.  

What does the future hold.
Well! our lack of landfill space is well publicized, the need to remove kitchen organic waste from landfill to prevent the build up of methane gas is well publicized, the need to reduce our packaging waste is well publicized and the need to preserve our dwindling peat bogs is well publicized. What’s not so well publicized is composting resolves these and many more waste disposal issues at source, in your home. That’s a 30% reduction in waste transportation alone. Soon we will all have to Slim down our bins by composting.
























Urban. Composting. Ltd, 83 Newsome Road, Huddersfield, West Yorkshire HD4 6ND
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