If you want the most rewarding first step into edible gardening, growing spring onions in Singapore is hard to beat. Also called scallions, these slender green stalks are one of the easiest things you can grow at home, because you can regrow them for free from the very roots you would normally throw away. All you need is a sunny windowsill or balcony, a glass of water or a small pot of soil, and a little patience. This guide shows you how to turn kitchen scraps into an endless supply of fresh green tops in our warm tropical climate.
Why Spring Onions Are the Perfect Beginner Crop
Spring onions grow quickly, take up almost no space and forgive plenty of mistakes, which makes them ideal for a compact HDB flat or a small balcony. Because you harvest the green tops rather than a bulb, the same plant keeps giving for weeks. Snip what you need, and it simply grows back.
Best of all, they cost you nothing to start. The next time you buy a bunch from the market or supermarket, keep the white root ends instead of discarding them, and you have your planting stock ready. Our steady warmth and bright light mean spring onions grow happily all year round here, with no seasons to wait for.
Regrowing From Kitchen Scraps
This is the classic method and the most satisfying. When you use spring onions in cooking, cut them a few centimetres above the white root base and set those root ends aside.
You can regrow them two ways:
- In water: Stand the root ends upright in a small glass or jar with just enough water to cover the roots, leaving the tops above the waterline. Place it on a bright windowsill. You will often see new green growth within a day or two.
- In soil: Plant the root ends upright in a small pot of potting mix, roots down, with the white base just below the surface. Water lightly and keep the soil moist.
The water method is wonderfully easy to watch and perfect for a kitchen counter. The soil method is better for the long term, because plants grown in soil draw on nutrients and stay productive far longer than those in plain water alone.
Change the Water to Avoid Stagnation
If you grow your spring onions in water, this step matters in our climate. Standing water left too long turns cloudy and stagnant, and open containers of still water can become a breeding spot for mosquitoes, which is a real concern in Singapore.
Change the water every one to two days to keep it fresh and clear, rinsing the roots gently at the same time. This keeps the plant healthy and removes any risk of still water sitting around. For this reason, many people start their scraps in water and then move them into a pot of soil after a week or so, which sidesteps the stagnation problem entirely and gives a longer, stronger harvest.
Water Versus Soil at a Glance
| Factor | Growing in water | Growing in soil |
|---|---|---|
| Ease of starting | Very easy, just a glass | Easy, needs a pot and mix |
| Upkeep | Change water every one to two days | Water when topsoil feels dry |
| Mosquito risk | Higher if water sits still | Very low |
| How long it lasts | Weeks; growth weakens over time | Months, with regular harvesting |
| Best for | A quick kitchen windowsill supply | A steady, longer-term crop |
Light, Watering and Placement
Spring onions want bright light to grow lush and green. A windowsill or balcony that gets several hours of light a day is ideal. In too dim a spot the growth turns pale, thin and floppy, so give them your brightest available position.
For plants in soil, keep the mix lightly moist but never waterlogged, watering when the top of the soil feels dry. Use a pot with drainage holes so excess water escapes freely, since our frequent rain and humidity can otherwise leave the soil soggy. A sheltered balcony spot protects the tender tops from strong wind and battering downpours.
Harvesting the Green Tops
The joy of spring onions is the cut-and-come-again harvest. Once the green tops reach around 12 to 15 centimetres or more, snip what you need with clean scissors, leaving at least a few centimetres of the plant standing above the roots. From that remaining stub, fresh growth pushes up again within days.
Harvest a little and often rather than pulling up the whole plant, and a single set of roots keeps you in fresh scallions for several rounds. Over time, plants grown in water alone gradually tire and produce thinner regrowth, which is the signal to start a new batch from fresh scraps or move them into soil for a longer run.
A Note on Washing and Food Safety
Because these are homegrown edibles you will eat fresh, give the green tops a good rinse under running water before using them in cooking, just as you would with any market produce. This clears away any dust, soil or residue and keeps your kitchen harvest clean and safe.
Common Problems and Fixes
- Pale, thin, floppy growth: Not enough light. Move to a brighter windowsill or balcony.
- Slimy roots or cloudy water: The water has gone stagnant. Rinse the roots, refresh the water more often, or shift the plant into soil.
- Weak regrowth over time: Plants in plain water eventually run out of steam. Pot them into soil, or start a fresh batch from new scraps.
- Yellowing in soil-grown plants: Often overwatering. Let the topsoil dry and check that the pot drains well.
Fresh Scallions, Free and Year-Round
Spring onions prove that you do not need space, money or experience to start growing your own food. A handful of leftover root ends, a bright windowsill and a splash of fresh water are all it takes to keep a steady supply of fragrant green tops in reach. Change the water often, wash your harvest, and enjoy the small daily satisfaction of snipping your own scallions straight into the wok. Once you are hooked, it is a natural first step towards a whole windowsill of easy homegrown edibles.