For those who have been asking/are curious, this text summarises my experiences with composting here in Singapore from end Jul 2019 to date.
Please note that the form of composting that I’m doing is known as aerobic composting. I’m not interested at this stage in anaerobic/bokashi composting or vermicomposting (composting with earthworms). I now live in a 3-room HDB flat and have only the small common passageway just in front of my flat to do whatever gardening activity. Hence, I am limited by space and the necessity to keep things as clean as possible so as not to inconvenience neighbours in any way.
Why I am not into vermicomposting: I’m not afraid of earthworms. But I do not want to worry about maintaining the health, longevity and safety of these worms while I engage in my experiments.
Why I am not into anaerobic composting: – The anaerobic forms of composting mean that you combine a fermenting agent (be it in a liquid or bran form) with the food waste. This mixture is stored in an air-tight container for a few weeks until the waste matter becomes pickled. Then you bury the pickled matter in the ground for the decomposition process to complete itself. This pickling supposedly speeds up the rate of decomposition, plus allows you to get rid of cooked food and meat-related waste as well as plant-based waste.
– However, the two-stage process sounds one-too many a stage for me. I do not like to cook meat and actually prepare more plant-based food to eat at home; so I do not usually need to dispose of much meat-related waste. I also have no access to a plot of land where I can bury the pickled stuff. To rely on this method of composting means that you must factor in the purchase of the fermenting agent as part of your continual cost outlay.
A) Preparation of Composting Equipment
What I use: – old plastic pail/waste basket/pail-sized containers
– old t-shirt cloth to cover the plastic containers
– 4 large loops of sewing elastic
– 2 spades
– 1 hand-operated drill
Currently, I have recycled 4 containers that I already have. Although larger containers would be nice so that I can compost bigger volumes, these 4 containers suit for the moment as they are relatively easy to store and the compost within can be turned easily with a spade.
The aerobic form of composting means that air/oxygen must circulate amidst the composting matter so that the decomposition can take place evenly throughout. Hence, this method means that you need to physically turn the compost every one or two days. This is where the spades come in: first to mix the various waste matter when I start the process, and then to turn the compost on a regular basis (takes a minute or two each time).
Ideally, all sides of your composting bin should have holes to allow for air circulation (plus also for water that materialises from the composting process to drain out). However, too many holes will invite pests in the tropical heat of Singapore, plus it could potentially be messy if stuff leaks out from all over (not good if you must keep your surroundings neat and clean). So if you make holes, punch small holes at the bottom of your container to at least allow water (‘compost tea’), if formed, to drain out on to a pot holder, thereby minimising having stinky, water-logged compost. I invested in a hand-operated drill to make holes at the base of 3 of my containers.
To help drainage and separate the compost from any ‘tea’ that is formed, I lined the bottom of each bin with a layer of leca.
As an experiment, I did not punch holes at the bottom of 1 blue pail. While my first few batches of compost were more or less trouble-free and produced fluffy and nice-smelling compost quite early on, subsequent batches in this blue pail developed a sour, water-logged smell, indicating the compost was too damp. Although technically speaking you can compost in any container without holes, this experiment proved that it is wiser to have holes at the bottom of your composting bin so that ‘compost tea’ can easily drain away, allowing your compost to be relatively drier.
(According to my research, you can collect ‘compost tea’ and water/fertilise plants with this liquid. Some people say you can use the liquid as it is; others say you need to dilute the liquid in water first before applying it as plant nourishment.)
I tried covering 1 container with its original lid. A lot of condensation built up within that container. No good. That’s when I tried using a basket to cover the compost, but this was useless as fruit flies began to appear through the weave of the basket and multiplied crazily. That’s when I started using recycled cloth, secured over the tops of the containers with the elastic loops, so that the compost could ‘breathe’ and yet pests were kept out as far as possible. (While I’m not able to keep away all tiny insects, I’m proud to say I have yet to detect the presence of cockroaches and rats.)
B) Stuff for Composting
What I use:
– ‘Greens’: all kinds of uncooked vegetable/fruit waste, steamed/boiled vege matter (e.g. tea leaves, non-plastic tea bags, maize cores, ginger strips leftover from making ginger tea)
– Crushed egg shell (the only thing of animal origin that I put in my compost)
– ‘Browns’: waste paper/cardboard
– Starting agent: store-bought compost
I focus primarily on composting plant-based matter that have not been contaminated with oil partly because of my diet, and also because I wanted to reduce the possibilities of creating bad odours and attracting rats and cockroaches. When I eat eggs, I tend to eat them boiled; so boiled egg shell has no wet residue. However, if I do use raw eggs for my cooking, I make sure the egg shell is cleaned of egg residue before I put it into the compost pile. I have not tried composting starchy stuff like leftover cooked rice/pasta for only occasionally do I cook rice/pasta at home.
I tend to accumulate a day or two of waste vege/fruit matter in closed plastic containers that I put in the fridge until I have time to add the stuff to the compost pile. In tropical Singapore, the use of the fridge and closed containers are necessary to retard the process of decomposition and prevent odours from developing and spreading in my fridge/kitchen.
I’ve read that some people accumulate and freeze their waste vege/fruit matter until they are ready to use the stuff. I have experimented with this freezing method as well. The only catch is that the process of defrosting generates extra moisture from condensation (especially in hot and humid Singapore), which has forced me to be more careful about the proportion of ‘greens’ and ‘browns’ that are mixed together. (Please see below for more information about ‘greens’ and ‘browns’.)
Regarding seeds within waste vege/fruit matter: I tend to add these seeds into the compost. Because I do not compost in high volumes or use a method that would ‘cook’/pickle the compost, such seeds have germinated as I compost. If I do see these seedlings, I just uproot them and leave their bodies to decompose in the compost.
Quite a few years ago when I formerly lived in a condo, I tried composting without doing any research and I ended up with a stinking goop, which discouraged me from further composting. Before beginning composting this year, I read up online on the various methods of composting and this was when I found that for successful composting in the aerobic fashion, you must have a balanced mixture of ‘greens’ and ‘browns’, ‘greens’ being fresh plant matter, ‘browns’ being waste paper/cardboard, even stuff like dried leaves.
I haven’t researched deeply on this, but apparently the ‘greens’ will contribute nitrogen and the ‘browns’ will constitute the carbon portion of the compost. However, I see it in far simpler terms: the ‘browns’ help to absorb the water created during decomposition and provide bulk to the compost, whereas you just get mushy, smelly goop if you let vege/fruit waste decompose on its own.
What sort of ‘browns’ should you put in the compost heap? Here there is some debate out there in the online world about what can be used in composting since there are different grades of paper and cardboard that you can come across, printed with different types of ink and may/may not have a glossy/plasticised surface.
My general rule of thumb: the less ink and glossiness, the better. If the paper has been printed all over with all sorts of ink and has a glossy surface, I leave out. Similarly with cardboard, especially those with heavily plasticised surfaces. However, most cardboard packaging tends to be printed only on 1 side; if its surface is not too plasticised, I use it for composting. I’ve heard that paper receipts should not be used because of the chemical composition of the paper and inks used; I’m not sure about this aspect; nevertheless, I am currently using such receipts for composting.
I make sure that all staples and plastic layers (e.g. plastic tape, plastic windows on business envelopes, plasticised surface of very thick cardboard that is easy to tear away and still leave behind usable brown matter behind) are removed before I use the paper/cardboard. Also, try to have a good mix of different types of paper/cardboard used as ‘browns’. Using only paper tends to promote sodden compost. Because cardboard is more water-absorbent, the presence of cardboard will lessen clumping.
Now here comes the time-consuming aspect of the composting that I do. Because I am working with space constraints and lack access to an actual piece of ground, I need my compost to decompose as fast as possible. To accelerate the rate of decomposition, I make sure that I tear/cut up both my ‘greens’ and ‘browns’ into small pieces (around 1 to 1.5 cm max in length/width) before putting into the compost bin. (Consequently, I have built up a stockpile of cut/torn paper and cardboard to use as and when.)
Usually you can just mix whatever waste material together without having to cut up the material and let nature do its work; however, the larger the size of the material, the longer it will take to decompose. If you cut up the waste material real small and are able to get the balance between ‘greens’ and ‘browns’ right, by around the one-month mark, about 75% of your waste material will have disintegrated and you will find it hard to distinguish what used to be ‘green’ and what used to be ‘brown’.
To start off, I mixed the ‘greens’ and ‘browns’ with store-bought compost for the store-bought compost has the necessary microorganisms etc. that can kickstart the composting process. You can easily use soil, instead of commercial compost.
C) My Process of Aerobic Composting
To begin composting, mix a combination of ‘greens’ and ‘browns’ with pre-existing compost together such that you can see pre-existing compost dusted among the particles of ‘greens’ and ‘browns’. Then leave nature to do its work. Every day or every other day, open up your compost bin and give the compost a good stir so that fresh air can circulate amidst the compost.
Different online resources recommend different proportions of ‘greens’ and ‘browns’. Generally, what has worked for me is a 50%-50% ratio, which I eyeball. The proof of whether you get the ratio right is what happens to your compost over time.
You can tell if the mixture is too damp if:
– there is excessive clumping
– there is a sour, water-logged smell (compost should smell earthy)
– a layer of fine mold develops on the surface of the compost
– a lot of ‘compost tea’ is leaking out of the bottom of your compost bin
If the mixture is too damp, just mix in more ‘browns’.
I have yet to encounter compost that is too dry. However, my online reading says this problem is easily solved: just squirt some water into the compost and give a good stir.
Once you start a compost bin, you can continually stir in new vege/fruit waste each day until the bin is full, taking care to also add equivalent measures of ‘browns’ so as to keep the ‘green’-brown’ proportion right. When the bin is full, try not to add in new waste matter so that whatever is already in the bin can decompose collectively as its own rate, without having to accommodate new waste. As the decomposition gets into full swing, you will notice that the volume of compost will decrease over time and the bin will appear less full. In the meantime, start another batch in a new bin.
Day#1 and Day#2: The compost looks like what it is: a mix of ‘greens’ and ‘browns’ with a dusting of pre-existing compost.
From Day#3 to about end of Week#3: This is when the compost looks the most disgusting. Just keep stirring every day or every other day.
By around Week #4: You will notice that clumping is less obvious. Around 80-85% of the ‘greens’ (depending on the type of ‘greens’ you put in) and about 70-75% of the ‘browns’ would have disintegrated into a nice crumbly mess. The more you leave the compost alone, the proportion of crumbly mess increases.
D) Using the Compost
Ok, I am still experimenting with this aspect. Some online readings say you can start using the compost at 1 month. Others advise waiting up to 3 to 6 months so that the PH levels will become more optimised to promote plant growth.
My observation: Seeds within the compost can start sprouting by the end of Week #2 onward, especially when you do not turn the compost for several days. My conclusion: Those who say you can begin using the compost at the end of Week #4 are valid.
For my first 2 batches, I left them alone until Week #8/Week#6 when I layered them between soil in pots. Then I left the pots alone for about another 2 weeks before I attempted to plant anything within. The gingers and the spring onions (and two germinated pumpkin seeds) are now growing fine.
Because I wanted to start new batches of compost and Batch #3 smelt water-logged, I took Batch #3 out of the compost bin/s at around Week #4 and layered it between soil in various pots. I will leave these pots fallow for a longer time than I did before.
Batch #4 is now at about Week#4 within the compost bin and is in the beginning stages of crumbling. I started Batch #5 this week.
May the above text be of use to you.