The start of Johanna’s life
We have had our Green Johanna hot composter for over 6 months now and have been feeding it/her with waste food, shredded paper and green vegetable material. I say waste food but we don’t really waste food! The sort of food waste we put in it/her is vegetable peelings, chicken carcass, fat and any waste product from the making of our marmalade. The idea is to get the compost to a temperature of between 45° & 65° C. At those temperatures even dead bodies will break down. I will come onto that later.

You can see that we started building temperature to 46° C a couple of weeks after we started feeding her. All sorts of insects were attracted to her and whenever we lifted the lid to add more, we were engulfed by a mass of flies, but not your average fly, tiny little ones more like fruit flies. Over time the heat increased and every time we lifted the lid, condensation poured from the underside. All good signs we thought.

Dealing with a pesky pest
Some while later, I noticed some digging on the ground adjacent to Johanna and underneath her. This looked suspiciously like a rat to me. Rats are a big problem if you put food waste on a conventional compost. Johanna has a perforated plastic base which is designed to let in worms and grubs from the soil to work on the compost above. It is supposed to keep out rodents but until I can empty Johanna, I won’t know if it has been successful in the this respect. I have nothing directly against rats nor wasps for that matter. They both serve a purpose in the wider environment but I don’t like them in or near my home.
I then began to trace the route the rat was using into the garden. At the same time Nicola had noticed that crumbs she had left out on the bird table were disappearing completely, which we thought was unusual as the birds usually leave some remaining. I decided to dust off my son’s air rifle and wait for Roger the rat to arrive. He climbed up the vertical post under the bird table and then overcame the overhang of the table to arrive on top to feed. With our our utility room window already open, I took careful aim and Roger was dispatched without knowing what had happened. Since that time we have not seen evidence of any of Roger’s friends appearing.
The thought came to me that I ought to put Johanna to the test! I therefore introduced Roger to Johanna and we will see what happens.
Temperature control
Occasionally Johanna’s contents need a little mixing. She comes with a plastic stick with a collapsable arrowhead on one end. As you insert the stick into Johanna, the sides of the arrowhead collapse against the shaft of the stick. When you pull the stick out, the arrowhead sides fall away from the shaft and you can lift a layer of compost and aerate it. By doing this a number of times, it ensures the composting process is working at its best. Nicola has often looked at me rather askance when I have told her I am going to give Johanna a poke!
I fear that in her first season, I may not have cared for Johanna as well as I might. During cold weather, at average temperatures below 5° C over a number of days, she can struggle to maintain her temperature and it is advised to give her a winter jacket. When I looked online before Christmas, I was too late. Everywhere I looked these winter jackets were sold out. I made a rather makeshift jacket out of discarded bubble wrap but that didn’t last long. There was still a fair amount of insect activity inside with condensation under the lid, so I knew she was still alive.

Whilst writing this blog I have found that the online stocks of winter jackets for Johanna have been replenished. Having purchased one and jacketed Johanna, her internal temperature changed overnight, even when there was a frost on the ground. I soon learnt that these jackets need managing because Johanna can get too hot and actually start cooking instead of composting. A sign of this was finding maggots on the outside of Johanna. Clearly these poor little chaps had decided that life was a little hot on the inside and they fancied their chances in the wider world, much to the delight of Bob our resident Robin!
As the depth of the compost increased inside Johanna, the load on the collapsable arrowhead on the supplied plastic aeration stick became too much for it. The last time I retracted the said stick, the arrowhead was missing. I therefore invested in a more robust metal aeration stick which can cope with the extra load.
There will be another update on our Green Johanna later in the year.