CHENNAI: Composting, at first sounds to be a creepy and smelly process and hence is the usual first mental block for people in taking it up. However, folks who compost regularly will assure you that if it’s done right, then this is one of the simplest things that can be done to save the environment. Plus it smells heavenly just like the first rain.
But first, what is composting? It’s recycling organic matter to send it back to mother earth. In terms of composting at home, it is a process wherein kitchen waste gets decomposed into healthy nutritious compost that can be used in your garden.
There are different types of composting available for an urban household. Mainly
Aerobic: Done by maintaining proper Nitrogen and Carbon ratio and lot of aeration. This is the most common.
Anaerobic: Bokashi is a prime example of anaerobic composting where in the composting container needs to be airtight.
Vermi Composting: is done with the help of a specific breed of earthworms which help in the composting the kitchen waste.
There is no one right method. Each method has its own merits and demerits. By Googling for information, you can get lot of resources as to what fits your budget and requirement.
Since I wanted something economical and a DIY setup, I chose aerobic process with blue water drums. In aerobic composting the basic requirement is Nitrogen and Carbon, in a ratio of 1:2 (1 nitrogen to 2 carbon). Nitrogen comes from the kitchen waste and flowers.
The carbon comes from dry brown matter, like shredded newspaper/cardboard, cocopeat, cocopeat enriched with microbes, soil, grass clippings, dried leaves etc. My source of carbon is leaf compost from a leaf composting unit near my house.
Each 80 litre blue water drum with lid costs about `300. Approx 30 kilos of leaf compost costs `100 and lasts for 2-3 months. Drill about 15-20 holes of approx 10mm around the drum to provide aeration.
Fill the first bin with alternate layers of kitchen waste and leaf compost. Add a layer of dried cowdung once in a week. It takes about 1.5 — 2 months to fill up. Also once a week, I roll the bin on the garden floor, so that the contents get mixed up thoroughly.
After the first bin is filled, keep it aside and start filling up the 2nd bin by layering kitchen waste and leaf compost. Repeat the process till the second bin gets filled as well. During this time the first bin would have composted. You can harvest the nutrient rich compost and use it as an additive to your plants or use it to prepare fresh potting mix.
While harvesting there might be a little bit of moisture in the bin, you can shade dry the harvested compost on a tarpaulin sheet for a day and then use the compost. Sometimes there will be larger chunks of uncomposted material, like groundnut shells, mango seeds etc. You can put them back into your composting container so that it goes through another round.
Tips
Once a week or so, you can add dried cow dung. This will give an extra punch to the end product.
You can also add manure from other animals, viz like goat/sheep/horse.
Especially for vermi composting, adding a layer of waste coffee grounds helps. You can source it either from your office coffee machines or coffee outlets. Or even better if you are filter coffee drinker who brews his/her own cuppa !
Place the composting setup in a shady but aerated place, away from direct sunlight and rain
Saw dust from wood can also be used.
Mix the contents of the bin every four days so that the covered areas get aerated.
One clear indictor of excess moisture is the presence of maggots. Though they do not cause any harm, its advisable to ensure proper moisture. Add more dry matter to control them.
Once in two weeks, you can add diluted Panchgavya or butter milk to increase the microbial activity and fasten the process.
There are a few products that market by saying that compost will be ready in 24 hours. Use your discretion while investing in them.