Are compostable bags really compostable? Part 4

Part 4 of an experiment in home composting.

I am conducting an experiment to see whether The Guardian’s compostable bags do actually degrade in a home compost heap.

I checked up on the heap again on Sunday 1 September, four weeks after the last check and eighteen weeks after I started the experiment. Again, I removed all the material carefully with a spade and trowel, placing it all into a large bin.

The first item I came across was the Happy Pear compostable pouch which I placed in the heap just four weeks before. It hadn’t decomposed much – if at all – as you can see from the picture below:

I didn’t expect to find much progress on this, certainly not after four weeks. The label says it is designed for industrial composting, so I’m not very optimistic that it will breakdown in a domestic situation. But we shall see.

Further down was the remnants of the compostable cup which I had added in July, at Stage 2 of the experiment. This has now further disintegrated further, so I’m pretty confident that this will vanish completely in due course.

Of the clear film bread wrapper left in the heap at the same time, I now found nothing. I can therefore record that this was composted completely within eight weeks.

Finally, I dug right down to the bottom of the heap to see what was left of the initial two compostable bags. These have been further reduced to a few very small scraps of compostable film:

It’s not now possible to tell from which of the two bags the scraps come, which is good news. It seems to me likely that there won’t be anything discernible by the time I next open up the heap, but we will see.

Finally I have decided to add another item to the heap: a compostable coffee cup made by Down2Earth Materials in Cork. (This firm may well have made the earlier cup which I placed into the heap in July, which you can see above. Unfortunately I didn’t keep a note of the manufacturer which is why I’m adding a new cup at this stage.)

Here’s the cup:

And here it is in the heap:

Once again, I’ve put all the part-composted material back, and topped the heap up with plenty of new kitchen vegetable scraps and garden waste. I will take another look sometime in late October.

Part 1, 28 April 2019. 
Part 2, 7 July 2019.
Part 3, 4 August 2019.

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Are compostable bags really compostable? Part 3

Part 3 of an experiment in home composting.

I am conducting an experiment to see whether The Guardian’s compostable bags do actually degrade in a home compost heap.

I checked up on the heap again on Sunday 4 August, four weeks after the last check and fourteen weeks after I started the experiment. Again, I removed the material carefully with a spade and trowel, placing it all into a large bin. A few inches down, I came across the material I had deposited four weeks ago. On the left you can see what it looked like then – a paper cup and a large transparent bag, which had been a bread wrapper.  I was pleasantly surprised to see that there is very little left of the transparent bag – in fact the printed label is the only distinguishable bit remaining. Here is what it looked like:

So hats off to NJB who say they make a compostable film. My experiment would seem to justify this claim. The compostable coffee cup has decomposed less, but it looks as though it is also on the way to breaking up completely.

I carried on removing material in order to reach the bottom of the heap, where the two original compostable bags were placed back in April. Here is what I found:

There is now very little left of either bag. The pieces shown above were the only traces of both, and I therefore have every hope that there will be nothing left to report next time round.

My latest addition to the experiment is a pouch which once contained Happy Pear granola, manufactured by the Israeli company TIPA. The packaging tells you to put this into ‘industrial composting’ (i.e. a brown bin) but as I only use our brown bin very rarely, I decided to see how well it goes in a home compost heap. Here is how I left it:

I’ve now returned all the compost to the heap. I will keep on adding more material on top and we will see what it all looks like again in a month or two.