I’ve tried composting kitchen waste over the years, both in a bin and in a heap. However I have to admit, I have failed. Recently I have been trying another way – Trench Composting, burying food waste in a trench. Even after just a few weeks, I can see this is the method for me. So much of your food waste can be composted and as you will find, some of our other household waste from cosmetics and cleaning supplies. Would it work for you too? Find out how you can use your food waste to create rich humus, a better microbial environment in your soil, encourage worms, spend less time watering and feeding your plants and grow the healthiest, most delicious plants. You can also tackle global warming because, this method, using trenches or pits to compost does not produce methane gas. So what is trench composting? How do you do trench composting?
The Problems with my Compost Bins
Firstly, I’ll tell you about my previous attempts, the uninspiring part of this blog! My black plastic compost bins got too hot and deformed. Humus did not tumble out of the hole at the base and I had to struggle to remove the bin from the contents to get a good look. I then had to separate the small amount of humus from the unrotted materials and put everything back in the top of the bin. As the bin had changed shape, the lid never went back on and the cover refused to go back in its slot. Likewise, it was not exactly easy to turn the contents. The amount of usable compost (about a shovel full) was hardly going to enrich my garden bed.
My Failed Compost Heap
Now I have a compost heap, but it looks unsightly, could attract vermin, takes up a lot of space and hasn’t given me any useable compost. Plus I am limited with what kitchen waste can go on there. That’s mainly because I have forgotten to turn it. If I had turned it I might have attracted newts and slowworms, but still probably also the hairy mammals with nearly hairless tails. I’m just not good at tending to compost and neither my garden or the amphibians were benefiting. I’m clearly not that keen on the double handling! Though to give some credit a potato plant had established itself on the edge of my heap. It meant that still lots of food waste was being disposed of in my dustbin and being taken off to landfill. When household waste festers in black bins bags in landfill site, undergoing anaerobic fermentation creating lots of methane – one of the causes of global warming. With the trench or pit composting method, the air in the soil gives support to aerobic microbes which do not create methane.
The Dig It Once, Trench Method!
So imagine my delight when I found there was another way, the Trench Method. I immediately, set my plan in action and dug a trench along one end of my vegetable patch and gemmed up on the method.
It involves creating three strips side by side. One for your active trench. The second is for you to stand on so you don’t compact the soil. The third is for you to plant. The uses of each strip are rotated each year, so every bit of your vegetable plot or flower garden gets enriched over the course of three years.
Here is a diagram (thank you to The Gardening Cook)
It is also possible to dig pits instead of trenches and it might be more appropriate with some gardens.
Aim for a trench of 1 ft in depth. Tip your kitchen waste in a section of the trench and dig the kitchen waste in with some of the excavated earth. Top with the remainder of the earth, giving a covering layer of at least 4 inches. I then watered the area I had back filled. I’ll keep a check that the soil stays damp for the benefit of the worms and soil microbes.
What Happens to the Kitchen Waste Once It’s In The Trench?
In essence, the soil bacteria and worms break the organic waste down and to turn my kitchen waste into to humus and super plant nutrition. More on worms later.
With all our tea leaves, we can create a moisture and nutritionally retentive soil so my plants don’t dry out. While we collect our own rain water, we ran out quite early in last summer. As we are on a water meter, the plants were on rations and didn’t develop to their full physical and intellectual potential.
The addition of humus makes the soil light in texture, better for drainage and aeration, enabling plant roots to grow and spread out and allowing rain water to percolate down to the root systems.
The soil will be enriched not only with humus, more moisture, but worms and microbes, which also help break down the minerals in soil and provide these resources to the plants.
How Long Does It Take?
Well, you know me, I’m rather impatient and like things to be quick. So have a look at this cross section of kitchen waste and soil which was mixed and layed in my trench about 4 weeks ago. Nearly everything has been broken down by soil bacteria.
Not Just Any Old Worm
Mostly when I dig my garden I find mainly the earthworker type of worm, Lumbricus terrestris, the ones that leave worm casts on top of the soil and live up to 1 foot below ground. They build burrows and like to eat soil and leaves. There are other species of root worm which you would rarely see. These two types, while very welcome in my garden are not key for composting. The earthworker worm likes to pull carefully selected fresh leaves into it burrow and the root worms are mainly interested in rotting wood and leaves.
For break down my kitchen waste quickly, I need the assistance of composting worms, of which they are four main species:
Tiger worm, manure worm, brandling worm (Eisenia fetida) – they have yellow stripes;
Dendras, blue noses, (Dendrobaena venta) – olive, brown or violet in colour;
Redworm, bloodworm, red wiggler – lumbricus rubillus – red or maroon in colour with a yellow underside;
Reg tiger worm, dark red to purple with some stripes.
They live in the first foot of the soil and eat decaying organic matter and live in manure heaps and leap piles. So my plan for my next trench is to add in some partly rotted horse manure which comes with free red worms. I am hoping they will team up with the bacteria to break down my kitchen waste even faster.
This website gives you more details about worm identification, https://www.opalexplorenature.org/earthwormguide
What sort of kitchen waste can use?
What can you add to a composting trench? A surprising array of kitchen and household waste can go into your pits or trenches. Another composting enthusiast, has listed 99 things you can compost.
It makes for interesting reading and now I know I can now add canned food liquids, dust bunnies, corks, wood ash, cut up cotton or wool clothing, cage cleanings from pets, razor trimming and finger and toe nails. I will also have a go at trench composting prawn shells, because it isn’t very nice to keep them in a domestic waste bin for up to two weeks! However, you can add more than kitchen waste to your composting trench or pit.
What Sort of Cosmetic and Cleaning Waste Can You Add?
We could certainly add to the list, because our household waste included our spent Soapnuts shells after they have been used for washing clothes, making washing up liquid and household cleaner; We pack them in brown paper bags, and not plastic, so everything we send you is planet friendly.
Some of my silk Dental Floss – the Dental Lace comes in a glass vial and refills are available; This floss packaging is of card and PLA (a biodegradable clear film)
My cellophane Henna packet, with some tape made of craft paper and natural rubber glue;
The end of my Miswak Stick– this now comes in a potato starch bag which is biodegradable too;
Our Olive Sticks can be composted too, as can their potato starch packaging when you have worked them down to a stub.
Buried deep underneath are some Seaweed fronds which have been mainly used for making natural hair conditioner, but also as a household plant treat.
Any of our padded envelopes which are filled with paper, our paper bags (scrunched up) to keep air in the soil
Can you Plant Straight Away?
Well, I’m going to find out, if you really need to wait for a full year before planted the composting trench. After two weeks of starting my compost trench, I dug a cross section of my two week old trench and surprising little of my kitchen waste was recognisable. I decided to go for it and I started adding potatoes which had sprouted in my pantry. I thought if they can grow in my compost heap, then they might be able to grow in my kitchen waste trench. Well, I had a little peep and these potatoes are starting to grow. I don’t think it will be long before the leave shoots appear above ground. I will have the definitive answer in 90 days!
Already in my next compost bin is filling up, lots of tea leaves and some spent Seaweed which has been used in a conditioning henna treatment. The worms, bacteria and in due course the plants should find the seaweed very exciting!
Going forward, my vegetable plants are going to be indulged and will, I am sure respond with abundance. My husband and I will indirectly eat both our food waste and our cosmetic and cleaning waste and our household will be closer to being Zero-Waste.