Non-UK Sales Blog Log In
Basket

0

Tag: Hot composting

When is my compost ready to use?

Posted on by Julie Halford

This was a question that two new owners of a Green Johanna were asking themselves in their first year of composting. 

Adam and Hayley decided to try composting with a Johanna last year following a few failed attempts with other composters.

They’re both vegans and wanted to produce their own compost to use for growing their own veg, as well as recycling their food and garden waste sustainably.   

  The standard test for when compost is ready for use is that it is dark brown in colour, crumbly in texture and has a pleasant, earthy smell like damp woodland. If you’ve been hot composting, the mature compost will no longer be generating heat. The original materials should not be recognisable. There may be a few items that have not fully broken down, such as sticks, bits of tea bags, corncobs, eggshells, fruit stones, compostable bags – these can be picked out and added back into the next batch of composting material.

 If there are other recognisable waste items and an unpleasant smell, the compost is not ready and should be left to continue breaking down.

Master composter Rod Weston, in his book A Gardener’s Guide to Composting Techniques, suggests a test to check if compost is ready if you are wanting to add it to soil immediately (immature compost added to soil can cause a temporary reduction in the availability of nitrogen and oxygen and create root-inhibiting organic acids).

The test involves putting a handful of compost in a plastic bag and sealing it for three days at room temperature. If when opened the contents have a pleasant earthy smell, composting is complete.

 Rod suggests that during the growing season immature compost is best used as surface mulch. If mostly composted it will finish breaking down in the soil. In autumn and winter it can be dug into garden beds. Some people prefer to leave their compost breaking down over winter to have it ready for the start of a new growing season. 

Horticulturalist and author Charles Dowding encourages a relaxed approach to the final product. In his No-Dig Children’s Gardening Book (also a good read for adults) he says that mature compost can be anything from ‘slightly lumpy and fibrous to quite fine and soft’. It all depends on the materials that went into making it and they will all decompose at different rates.

‘It doesn’t need to look perfect – woody bits in your compost make great food for fungi.’

He cautions against sieving compost as it can damage microbes.

What’s the difference between compost and humus?

The term compost describes materials that are still breaking down whereas humus is what’s left when breakdown is no longer taking place and the usable chemicals in the organic matter have been extracted by the micro-organisms.

It takes years for compost to decompose into a humus state. Even mature compost isn’t really ‘finished’ since bugs and fungi still have material to work on. Some gardeners have a bank of composters and leave the final one to break down completely into humus.  

A bumper crop

Adam and Hayley decided to leave their compost for about a year so they could use it in a compost mix for growing potatoes.

With first-time use of a Green Johanna, it can take 6-8 months for compost to be ready for use. After that, depending on conditions, it’s usually 4-6 months. With regular cold composting it’s usually between 6 months to 2 years.

Great compost accelerator

The couple also used a bokashi bin alongside their Johanna.  The pre-compost that a bokashi bin produces makes an excellent compost accelerator, raising temperature and speeding up decomposition. Fermented bokashi mixture is usually quite wet so needs to be balanced with plenty of carbon-rich materials. The bokashi mixture will then break down in the composter. 

 ‘Bokashi has become a really useful part of our composting process,’ said Adam. ‘We put all our food waste straight into the bin and give it a few sprays of Bokashi spray, then once it’s full and has been left to ferment we transfer it to the Johanna.’

It usually takes them around one to two weeks to fill the Bokashi bin with their kitchen waste, which is usually vegetable scraps along with some beans. They then use their smaller kitchen caddy to take food waste to the Johanna while the Bokashi bin is ‘doing its thing’.

Food waste provides the compost mix with nitrogen-rich content, which must be balanced with shredded carbon-rich materials (dead leaves, twigs, branches, wood chips, paper waste) and regularly aerated to get oxygen into the pile.

The verdict on the Johanna:

With previous composting attempts, the couple had experienced slow breakdown of waste materials with hardly any compost produced.  

 ‘The Johanna is much better built and works faster at breaking down all the waste,’ said Adam.

The couple feel their efforts with the Johanna and Bokashi have paid off – not only are they recycling all their food and garden waste nature’s way, but they also get to make their own delicious home-grown spuds. What’s not to like? 

How Bokashi boosts your hot compost

Posted on by Julie Halford

When it comes to boosting the composting process, we have found a Bokashi bin to be the perfect partner for the Green Johanna.

We recently carried out trials involving additions of fermented food waste from a Maze Bokashi bin to a Green Johanna and found that temperatures in the Johanna rapidly increased as a result.  

For our trials, we re-started a Johanna more or less from scratch, having previously removed large amounts of compost.  Using a permanently installed insulation jacket and large amounts of Bokashi bran and carbon-rich materials, compost temperatures were around 30 degrees Celsius. 

 We added the contents of a Bokashi bin that had been fermenting for 21 days, followed by a full 1kg bag of Bokashi bran.   We then added some mulch and stirred well with a garden fork, before completing the process with a thin layer of mulch. 

 The Johanna was then left for 48 hours.  Temperatures rose to 66 degrees Celsius whilst outdoor temperatures were in the 0-10 degree range.   After 48 hours we re-stirred to spread heat more widely through the Johanna.    Using two Bokashi bins in rotation we repeated this cycle roughly every three weeks and got the same results.

We used the Green Johanna in combination with a regular kitchen caddy (as the Johanna needs regular feeding to maintain the hot composting process), twin-bin Bokashi system, Insulating Jacket, Bokashi Bran as an accelerant and plenty of mulch.

Photos show starting temperature at 30 degrees Celsius/adding fermented waste from a Bokashi bin/ adding Bokashi bran/temperature at 66 degrees Celsius.

The Bokashi process was developed in Japan in the 1980s; the term means ‘fermented organic matter’ in Japanese.  It involves adding all your food waste, cooked and uncooked, to a specially designed airtight Bokashi bin, with the addition of Bokashi in the form of a fermented bran or spray. The food waste is compressed with a compactor to eliminate as much air as possible as this is an anaerobic process.  Once the bin is full, you close the airtight lid and leave for 2-3 weeks.  Many people use two or three bins to keep the process going.

The bacteria (lactobacilli) in the bran or spray will create lactic acid which will effectively pickle the food waste rather than letting it decompose as it would in a regular food waste caddy.  After a week or so, liquid should start to form in the Bokashi bin which should be drained using the tap.   This ‘Bokashi tea’ can be used as a drain cleaner or diluted for use as plant food.

 At the end of the fermentation period the waste food is a pre-compost mixture that can be added to a composter or buried in soil to become a soil enhancer. Its composition is such that virtually all its original nutrients, carbon and energy enter rapidly into the soil.   No greenhouse gases are released to the atmosphere as they are during regular food waste decomposition in landfill.

Bokashi composting has traditionally proven particularly popular in urban environments where traditional garden composting is difficult. 

Mark

How to get the most from your Green Johanna

Posted on by Julie Halford

With your Green Johanna assembled, it’s time to choose the ideal location.

Choose a spot that provides a flat surface with free drainage for any liquid produced. Make sure it’s also not too far from the house and easy to get to.

The Johanna has been designed to promote efficient composting. Vents leading in from the base plate allow air to flow upwards into the container. The twistable lid regulates the ventilation system helping you to adjust air circulation and temperature. The container’s round shape ensures there are no cold corners so heat is spread evenly through the compost, and the tapered design means that compost sinks towards the centre of the unit and not to its sides, allowing air to circulate and oxygenate the compost.

If you’re new to composting, a bit of basic knowledge will help you on your way but you will also learn as you go by paying attention to what’s going on in your bin.

Successful composting depends on three essential ingredients: materials, air, moisture.

Composting basics

 MATERIALS – The microbes in your compost bin need a diet that provides a balance between waste materials that are rich in nitrogen and carbon. In composting terms, nitrogen-rich materials are often referred to as Greens and carbon-rich materials as Browns.

Nitrogen-rich materials (Greens) include:

  • Food waste, fresh grass and leaves, plants, flowers, tea leaves, home compostable tea bags, coffee grounds. These items break down quickly and contain moisture so they keep the bin’s contents moist.

Carbon-rich materials (Browns) include:

  • Twigs, branches, dead leaves, paper, cardboard, straw, wood chips, sawdust. These contents are drier and slower to break down.

 A mixture that contains a 50:50 balance of nitrogen (Greens) to carbon (Browns) is a good place to start for composting. You may find that you have a lot more nitrogen-rich inputs (food waste) than carbon so it can be handy to store carbon-rich items such as paper, cardboard and autumn leaves so you have them ready to add with food waste.

 The smaller the waste items are chopped or shredded, the greater the surface area for microbes to work on and the faster the pile will heat up. Items that are added whole, such as apples or carrots etc, will take longer to break down. Egg shells should be crushed or ground. Garden waste should be chopped into pieces no larger than 5cms or shredded.

Getting the nitrogen/carbon ratio right can be a case of trial and error but you will learn quickly through paying attention to conditions in the bin. 

As the micro-organisms break down the waste, they generate heat. As the temperature in the compost fluctuates, the types of micro-organisms present also change.

AIR – The fastest form of composting is done by organisms that need oxygen.  To give microbes air to breathe we need to add air to the mixture by aerating the contents to make sure there’s oxygen throughout the bin.

You can create air pockets by adding the cardboard tubes from toilet or kitchen rolls whole and keeping cardboard egg boxes whole. Waste paper can be added scrunched up so that it provides pockets of air, or shredded. Cardboard should be torn up. Wood chips are useful as they hold structure and create pathways for air.

WATER – You want your compost pile to be moist, rather than wet or dry. The consistency of the bin’s contents should be damp like a wrung-out sponge.  Microbes struggle if their environment is too wet or too dry. They need water to live, yet too much moisture can limit the amount of oxygen they receive. If compost is too wet, it will start to smell bad. If this happens you need to add shredded paper and cardboard and aerate well so that moisture is absorbed.  

Add water to compost that is becoming dry by gently watering with a small watering can, preferably with rainwater collected in a water butt.

Adding food waste

Food waste can be added directly or in home compostable bags, never plastic. If you tie the bags, once you have added them to the Johanna make sure to break them open using the aerator stick to allow oxygen and microbes to reach the waste.

Add food waste and other Greens first, gently stirring these in with the older waste below.
This helps the micro-organisms working below to become part of the newly added materials.
Then cover with an equal amount of carbon materials (Browns) and gently stir again. If you
prefer you can premix these nitrogen/carbon materials before adding them to the bin. Finishing with a layer of carbon, such as dry dead leaves or shredded paper/cardboard, helps to prevent smells from food waste attracting flies and vermin.

The only food-related materials that are not efficiently digested by the Johanna are those that require a very long time to break down, such as bones, large amounts of cooking oil/fat, the hard shells of nuts and seafood (such as oysters and crabs) and avocado stones.

If bones are added to the Johanna they will not break down and it would be
necessary to remove stripped-down bones from the finished compost, which could present
a danger to dogs. For this reason we do not recommend that bones are added.

You can boost the breakdown process by adding bokashi bran (available separately), fermented waste from a bokashi bin, or a bucketful of mature compost.

The Green Johanna Insulating Jacket (available separately) helps to boost temperatures for hot composting and to maintain composting performance in colder weather for regular composting. It should be removed in hot weather or the internal temperature in the bin could become too hot for the composting creatures to survive (above 70 degrees Celsius).

And finally…

To access your finished compost simply unscrew the hatches at the bottom of the Johanna and remove the compost using the aerator stick or a garden hoe.

If you want to access larger amounts of compost that have been left to mature, you can unscrew and remove the Johanna’s top sections. Return any fresh organic waste to the reassembled composter to continue breaking down.

The Johanna was designed and originally manufactured in Sweden, but is now made for Great Green Systems in Droitwich, Worcestershire.

Can you compost in communities? Anthea shows how

Posted on by Julie Halford

When Anthea Rossouw tried to get people into composting years ago, they thought she was crazy.

‘I just got blank stares,’ she recalls. ‘At the time there weren’t studies that proved what composting could do. People just wanted to throw things in the bin. Composting was a controversial idea.’

But Anthea is passionate about the environment and has a way of bringing people with her. Using workshops to show how to use the Green Johanna, she introduced composting to the housing complex in West Sussex where she was living at the time. This was so successful that it spread to other housing developments and businesses.

Anthea had been a keen recycler for years and pursued her interest by enrolling on the West Sussex County Council Waste Prevention Advisor programme delivered by the University of Brighton. So then when she was living in Walstead Court extra-care housing facility and saw piles of bin bags in the ‘rubbish room’ destined for landfill, she knew something could be done about it.   

With the support of the housing manager, Anthea showed residents and staff how to recycle food, garden and paper waste using three Green Johanna composters.

Her tutor at Brighton, Dr Ryan Woodard, had told her about Green Johannas and she thought they sounded ideal.

‘It was essential to get everyone on board though,’ she says.

 Anthea, front right, with other keen composters and the Green Johanna.

The workshops worked a treat. Waste disposal routines were transformed, as was the rubbish room, now that it was clear of bin bags containing food waste.

 Before long the residents were making their own compost and growing their own food and flowers. ‘We grew the most beautiful tomatoes,’ Anthea remembers.

Anthea approached the task methodically, weighing waste and tracking residual waste.  Waste to landfill was reduced by 55 per cent, black bin bags were reduced from three to one per flat per week. Over a six-month period 280 kg of food waste was diverted from landfill.

The communal gardens were not the only things that blossomed. Residents and staff reported that personal well-being and community spirit also flourished. The projects helped to keep people mentally alert and physically active, through taking waste out to the Johannas, crunching up cardboard containers etc. It also gave neighbours an added reason to chat to each other, acting as a conversational ice-breaker.

Anthea was then asked to introduce similar schemes to other housing associations and businesses. She also ran trials for DEFRA (Department for the Environment, Food and Rural Affairs) and won the Gatwick Diamond Green Champion award for her environmental work.

She then decided to try the same method of community food waste recycling in a very different place – her native South Africa. Here she introduced composting to struggling townships as part of her work with the Dreamcatcher South Africa Foundation that she had set up in 1991 to alleviate poverty by creating employment. In the community, waste was historically burnt at the dumpsite having a devastating impact on the environment and public health.

Anthea, second left next to Sir Trevor McDonald, receiving the Gatwick Diamond Green Champion award.

On a trip back home, she took three Johannas as luggage instead of suitcases, wrapping her clothes around the Johannas’ circular sections. Using the same training methods as in East and West Sussex, she installed three Johannas in a communal garden managed by local women known as Kamammas (a term meaning matriarch, or community leader).

Anthea says the Kamammas quickly took to working with the Johannas.

 ‘They found the composters didn’t attract dogs or vermin and they were delighted when they saw the quality of compost that was produced and the food they could grow with it.’ This trial was then scaled up to introduce another 25 Johannas.

The food that is grown with the Johannas’ compost is used in the women’s work providing tourists with traditional South African cuisine.  

A Kamamma introduces tourists to traditional South African cuisine.

Anthea divides her time between the UK and South Africa, and she is still in contact with the people she got composting back in the South of England. She is delighted – but not surprised – that the schemes she helped to implement are still going strong.

‘Any system must be sustainable, otherwise there’s no point. To bring about real change you have to go truly local. You need the people to make it work.

‘It takes around three months to introduce a composting project. After that people can stand on their own two feet.

‘Once you give people the skills, knowledge and confidence they become compost evangelists!’

After all these years, Anthea is still a big Johanna fan.

‘We used many other composters before settling on the Green Johanna. I underpin everything with baseline research and I knew the Green Johanna was the one.’

She still loves introducing beginners to composting.

 ‘They might know nothing now but you know they soon will. People become fascinated to know about all these little creatures in the composter doing their work.’

She firmly believes that if you pay attention to what’s happening in your composter you will learn  how to ‘speak compost’.

‘You soon learn to tell if you need to do something to bring good conditions back. If you haven’t enough garden waste, you can use paper product waste, such as toilet rolls, cardboard, shredded paper. If the contents look dry sprinkle a little water on top.’

The Johanna may have been designed in Sweden to cope with harsh Scandinavian winters, but it has happily adjusted to the South African climate, often turning ‘psychedelic green’ in the sun.

Whatever the shade, it’s still doing a great green job for the planet, wherever on earth it happens to be.  

Spare Parts