First Opening of Hotbin Hatch - Feedback Appreciated!

[MonsterMulch]

I started using the Hotbin properly around the beginning of April this year when I had almost weekly access to around 40L of grass cuttings. I had a false start over winter, but decided to clear it out and begin again as I think it was too wet and generally too cold without enough waste to keep the temperature up. It's been great, and I'm impressed how much I've been able to get in there only for it to shrink down again the next week ready for more!

Three months on I have opened the hatch for the first time and the results are posted. It's not quite what I'd expect, so I'd appreciate feedback including whether I should leave it in or remove it now.

The temperature has been ok, though got down to 40C a little more than I would have liked and in some cases lower. I think the volume and frequency of material I've been able to put in is where I may have slipped up and am aiming to improve. Because I work away often and we had a holiday in early June, there will have been periods where the hotbin may not have had any material for up to two weeks. After this time the telltale fluffy white foam appeared on the top of the pile (there seems to be remnants of this throughout the compost). I have usually found within 2 days of putting material in I get it back up in 50-60C range. In some cases I may then have overdone it, putting in 80L of grass cuttings and kitchen waste in one go (made up of 80-90% grass, the rest kitchen waste). I've been fairly regimented about the mix of material (in general I think I put in too much shredded paper and bulking agent, so I'm surprised it is this wet), and also made sure to cut waste small, 2-4cm. I've been using my own bulking agent, chipped wood that has been in a heap for >1 year. Some landscaping bark may have crept in, but not much. The paper has been shredded white office paper, mostly my own but some from an office nearby, I don't think any of it was shiny paper. I am about to start supplementing with shredded cardboard too.

The result in the pictures below is wet (but hopefully no wetter than normal), it is a mixture of browns and oranges in colour. It has no smell and it was warm to the touch (I would estimate between 30-40C). Some of the paper seems intact, but on contact it disintegrates - you can see the pictures of the wet mix once taken out has not discernible paper fragments. Once dried, I can see that the majority of the compost seems to be left over woodchips, but plenty of soil too. There was one worm in the bottom left corner! Who knows how it got in...

So I'm wondering whether I take this out and use it as mulch because it looks good once dried and has no smell, or leave it in because it is still warm and therefore it may be conditioned a little better in a month? I'm not really running out of space in the hotbin so it's not a problem to leave it for 1 month, but I know it can be a problem if I start compressing the lower layers too much.

In future, I'm wondering if I should be less heavy going on the composition of the waste and concentrate more on supplying volume. I've got another dalek bin, and that has been taking weeds etc that I probably could have put into the hotbin but I wanted to keep the hotbin for the better quality stuff (and was probably too lazy to mix in with paper/bulking agent at the time)!

Advice appreciated from anyone!

Dan

[Cumbriamom]

Hi, i have had a similar experience. Been hotcomposting since early summer 2021. All the compost looks more like mulch. I was expecting that for the first batch but not the third, fourth etc. I have been looking at a few posts today on here and think i will up the paper ratio a lot to see if that makes it less wet. I tried what you suggested and put the first batch back through but it didnt help. I am using it as mulch on my rhubarb, During the summer i used it for the bottom half of tubs and then filled rest with bought compost. It did work well for me and the plants were all healthy. So either works from my experience. Now on to add more paper from today. It sounds as if my material is too water content high.

[HotBinDjinn]

In your first picture, the compost does look a bit 'off colour'. It looks like some kind of biofilm has grown on it. It's hard to tell. Mine is almost always darker, though it's just as wet.


I've attached some photos for comparison. I Put my wet compost from the Hotbin into my Dalek and let it cure and dry a bit. The stuff that comes out the bottom is much better quality. Then I dry it a little and sieve it for potting or just remove the larger bits of bulking agent for reuse and put the compost directly on my veg garden. You want to get into a rhythm where you have your Dalek filled, you take a load out the bottom then empty part of your Hotbin and put it in the top of the Dalek. Then you have a constant supply of compost.

I've learned to go heavier on the bulking agent and cardboard (paper and cardboard mix is better). I also use semi-composted wood chips and large chunks of bark. Keep you Hotbin sheltered. Rain can get in.

If it looks composted, don't worry if it's warm. That's not necessarily a sign that the stuff at the bottom is composting, just that heat is transferring from the hotter layer above. Remove small amounts from the bottom regularly if possible and keep it topped up.