Urban Gardening Manual focusing on Effective Methods for Decomposing Organic Waste in City Environments
Composting is a valuable practice for urban gardeners, transforming kitchen waste into nutrient-rich fertiliser. This article explores efficient composting techniques suitable for small spaces and terraces.
Balancing Greens and Browns
A simple rule for a successful compost pile is to maintain a balance between greens (nitrogen-rich food scraps) and browns (carbon-rich paper, cardboard, or twigs). This balance helps achieve an earthy smell and prevents unpleasant odours. In hot composting, a ratio of 30:1 greens to browns is recommended, while for vermicomposting, a balance is crucial to prevent odour.
Composting Methods for Urban Spaces
Hot Composting
Hot composting is an effective method for small spaces, turning scraps into finished compost quickly. Aeration and turning techniques, such as tumbler spin every 2-3 days or forking turning every 3-5 days for larger piles, are used to speed up the process.
Compact Bins, Vermicomposting, and Bokashi
Compact bins, vermicomposting, and Bokashi are other methods suitable for urban composting. Vermicomposting, ideal for small kitchens with steady vegetable scraps, requires a balance of greens and browns to prevent odour. Bokashi, on the other hand, is suitable for very small spaces or apartments that need to handle meat and dairy. It ferments kitchen waste quickly (within 2 to 4 weeks), produces a nutrient-rich fertiliser without unpleasant odours or mould, and is suitable for limited spaces.
Troubleshooting
Slow Composting
In cases of slow composting, the quick fix is to shred, mix greens and browns, and turn to build heat. If the pile is compact, an aerator rod can be used to fix compacted spots.
Fruit Flies
To tackle fruit flies, bury scraps, add 2-4 inches of brown cover, and use a closed bin.
Wet, Compact Pile
For a wet, compact pile, the quick fix is to add coarse browns (twigs), turn, and lift the pile.
Bad Odour
In cases of bad odour, add dry browns, turn the pile, and check moisture. If the pile smells like ammonia, add browns and turn to restore air.
Setting Up a Composting System
A small toolkit is recommended for setting up a compact composting system. This includes a vermicompost bin, red wiggler worms, bedding, a Bokashi bucket, Bokashi bran, a hand trowel, garden gloves, a drip tray, pH test strips or moisture meter, and a small scale or kitchen timer.
Odor Control
Maintaining a balance of greens and browns, adding a thin layer of shredded paper after each food drop, and treating any sour smell promptly are essential steps for odour control. Bokashi requires adding Bokashi bran each layer, draining liquid weekly, and treating any sour smell promptly.
Testing Compost
The germination test is a quick test before using finished compost. Planting radish seeds in 50% compost 50% potting soil and observing healthy sprouts in 7-10 days indicates safe compost.
By adopting these efficient composting techniques, urban gardeners can transform their kitchen waste into valuable fertiliser, promoting sustainable urban gardening.
