Green Johanna – by Vicky

Jun 22 2017

Winter 2017

We’ve had the GJ up and running for 3-4 months now and put in a fairly reasonable amount  of waste and it’s still only about a third full so I guess it must be breaking down! 

Green Johanna

We’ve had no real issues. The GJ itself smells fine and, other than remembering to give the caddy a clean out after emptying it, it’s pretty straight forward to use. What’s interesting is how it’s encouraged a change in our behaviour at home. Gone are the days of wrapping up the bones from the roast, along with the dregs of gravy and last few veggies, and throwing them away in the black bag (I’m afraid that I haven’t got into the habit of making stock!) as it can now all go into the GJ.  My husband still has some reservations and is getting used to putting all the bits and bobs into the caddies, but I think that as soon as we see the compost at the other end, that will make a big difference.  What I’ve also noticed is that our black bag is taking much longer to fill, which is great – although now it’s mainly made up of packaging waste which is a whole different debate! 

Now the only question I have is about whether or not I can put the, er, ‘presents’ my cat brings us occasionally (mice mainly) into the GJ.  I haven’t quite been able to bring myself to do that yet, but I suppose it should be fine?  Any thoughts or suggestions are very welcome!

Green Johanna factsheet
Buy a Green Johanna from

Autumn 2016

I have long wanted to get rid of more food waste at home via composting, but had been reluctant to for a number of reasons.  These included vermin, worries over unpleasant smells and limited options on systems. When I was offered the opportunity to try the Green Johanna (henceforth known as the ‘GJ’!) which is described as an ‘all food’ composting option, I was intrigued to find out more.

Great Green Systems’ website describes it as “a hot composter which recycles all kinds of waste food – even cooked food, bones, meat and fish – into natural organic compost.”  But what really sold it to me is that it’s not open at the bottom like standard composters, avoiding the issue of vermin being attracted, as well as being roughly the same size and shape as an average water butt.

Green Johanna

The GJ arrived in a big box along with a small caddy and after looking up instructions on assembly and location online, my husband and I put the composter together and located it in a shady spot at the bottom of the garden.

Green Johanna

In part this was to avoid any issues with smell as I wasn’t sure what it would be like with warmer weather. The instructions say shade, as too sunny a spot could actually prevent the GJ from working most efficiently. The double plastic skin helps to maintain a pretty hot temperature, and any higher than that could mean that the useful bacteria inside that breaks the organic waste down to compost could be killed off. 

So then it was time to get started! We already had a large-ish plastic caddy that we used for veggie and fruit waste which we keep under the kitchen sink, so I put the new caddy next to it.  However, having experienced some lovely hot weather at the end of the Autumn, I would probably recommend sticking to just the small caddy – particularly if you are putting meat or fish waste (including bones) in there.  Meat, bones, dairy and cooked veg appear to get mouldy quite quickly and it can start to smell if you’re not emptying it that frequently – I was doing it every week or so but suspect that next Summer I’ll need to empty it more frequently.

But the GJ is amazing!!  Absolutely all food waste can go in there – egg shells (break them up to as small a piece as possible), meat bones, cooked veg, dairy products such as that last bit of yoghurt that you forgot about at the back of the fridge (!), bread, fish, gravy… everything.  You are supposed to mix some garden waste into the container along with the household food waste on a roughly 2:1 ratio, so every now and then I’ve got into the habit of adding some garden waste such as grass cuttings, leaves, twigs, etc. 

We already have a couple of composters for mainly garden waste so I rummaged around to find some red ‘composting’ worms which I transplanted into the GJ when I first got it going. I’m yet to use the stirring stick but I need to do that soon, as the advice is to aerate and mix the compost up every time you add a new load.