Want to learn how to grow vegetables in Singapore? If you are starting from scratch, here’s a beginner’s guide! There is a lot to take in so let’s start from the basics.
When I hold workshops on this topic or about soil, I often get feedback that there is too much information to retain all at once. It is important to note that growing vegetables is a journey and it’s difficult to learn everything in one sitting because it is easiest to learn when you can reference the information to real life experiences. The amount of sun, wind moisture, or temperature – or microclimate in general – is different from house to house. Trial and error is important, as are observational skills.
Getting Started: Grow Vegetables in Singapore
So what will you need? Some seeds, soil, pots and garden tools. Here’s a general checklist that you can refer to:
At this point you may be asking, “Where should I get seeds from?” or “What is seed raising mix?”, “How much should I water my plant?”,”What fertilisers should I buy?” or “Where to buy garden tools?”. I will gradually elaborate these details further in the post. But first, I will talk about how to get started when you grow vegetables in Singapore.
Which Vegetables Are Easy to Grow in Singapore?
For beginners, I always recommend growing herbs and green leafy vegetables before venturing into fruiting vegetables although I know that people want to start off by growing tomatoes. If you are curious and wish to do so, you can read this post on growing tomatoes successfully in Singapore. Cherry tomatoes do best in our climate, and pear tomatoes fare well too. Beefsteak tomatoes rarely do well here but Black Sea Man is a great one to try.
Herbs like dill, Thai basil, Italian basil are easy starter plants. Easy green leafy vegetables to grow from seed include kang kong, bayam (spinach), malabar spinach, lettuce (opt for loose-leaf and not tight heads), nai bai (tatsoi), and pak choy.
If buying herb and vegetable plants or swapping cuttings, some easy ones to grow at home include mint, curry leaf, laksa leaf, sawtooth coriander, kaffir lime leaf, pandan leaf, Indian borage and chives, longevity spinach, Chinese violets, Surinam spinach, Brazilian spinach and moringa. Spices like lemongrass, wild pepper, ginger and turmeric are also easy. Some of these plants are water-loving and you can consider growing those which favour the same conditions together.
Many people have issues growing rosemary at home, and the key to this is drainage. After purchasing the plants from the nursery or sometimes, the supermarket, there is a high probability that you need to repot the plant into a soil mix that includes sand, perlite and/or pumice, in order to recreate its preferred growing conditions in the Mediterranean.
In other words, if you can provide the ideal microclimate to plants, you can grow these vegetables in Singapore. There are some limitations to this of course. Living in a tropical climate means that we are not able to grow certain plants from subtropical and temperate regions, or get it to flower and fruit successfully.
If you are feeling more adventurous, some easy fruiting plants you can consider growing from seed include beans (green beans, winged beans), bittergourd, okra, gooseberries and luffa (let it dry on the vine for sponges). Chilli, eggplants and tomatoes require a bit of trial and error to get it right when growing from seed. It is not unusual to experience whitefly among these plants, this pest can be found on the undersides of leaves.
Pest management can involve the use of sprays, yellow sticky traps (you may end up trapping beneficial insects or even lizards), use of exclusion netting, eradicating ants (yes, they can bring pests to your plants), or by plain old squashing with your hands. There are many other pests that you will be acquainted with in due time as part of your gardening journey.
How to Sow Seeds
The rule of thumb for sowing seeds is to plant it at a depth of twice the seed’s width. Seeds take different shapes, for example, basil seeds are small and round, cucumber seeds are usually long, large and tapered. Therefore larger seeds should be planted deeper than smaller seeds. The time required for seeds to germinate also vary. You will find that okra, basil, and many herbs and vegetable seeds sprout faster than eggplant seeds, which can take around 10 days to germinate.
Seed raising mix is a pre-mixed growing medium which may contain worm compost (also known as worm castings), coir peat, sand, perlite, compost or other soil amendments to keep it moist yet free-draining and suitable for seeds to grow in. Some people grow seeds in compost and you can choose to do so but make sure that you sift it (yes, a soil sifter is a thing) so there are no large bits of bark or anything that can obstruct the growth of your seedlings.
Personally I prefer to mix my own seed raising mix. There are recipes readily available online, but you will find that a pre-made version available in-store will be cheaper, unless you can get hold of soil amendments cheaply. A small bag of sand or perlite costs around $2 in Singapore, and if you have access to worm castings or compost for free, then you must as well mix it yourself. Otherwise you can always pick up a bag of seed raising mix from Greenspade here.
You may plant your seeds in a small plastic pot, or a plastic punnet (a few types can be seen below), or coir pots of varying sizes, or you can sow direct into the ground. Whichever you choose is up to you. The plastic punnets require you to transplant to a bigger pot or into the ground at a later date. You can prick out the seedlings (using two satay sticks) for punnets with smaller cells, or chopsticks for bigger cells. The coir pots allow you to plant it directly into a larger pot or garden bed without disrupting the roots.
If you plan to sow direct, I would suggest preparing the garden bed or pot first. You can do this by digging in some compost, worm castings and well-rotted animal manure — such as sheep or chicken manure.
After sowing your seeds in seed raising mix or soil that you have prepared for planting, pat down the soil so that the seed has direct contact with it. Afterwards, water it using a spray bottle, trying not to displace the seeds. If sowing directly into the ground, dampen the soil before planting, and then water lightly.
Make sure to water religiously so that the soil does not dry out. But also, do not overwater so as to avoid the growth of mould, or worse, cause the seed to rot. Bean seeds are susceptible to rotting in soil that is too moist, so in this case it is best to water once and wait till it germinates. However if you find the top of the soil drying out because it is hot and/or windy in that location, then it is ok to lightly spritz the soil again and put the seeds in another location where it is exposed to bright light for several hours, but not necessarily direct sun.
How to Care for Seedlings
Light is crucial. Too little and the seedlings will become leggy in its quest to seek light, or when exposed to direct sun, it can be too much too soon. Bright light refers to indirect light from the sun, meaning that the sun is not directly shining on the plant. Once your seedlings are established and have grown its true leaves (the next set of leaves after the seeds initially produces leaves, see above), you can begin to give it more sun and even transplant it.
This process of acclimatising the seedlings to the elements is known as hardening off. You can do this over a period of a week, gradually exposing it to more sun over the week. Once the plant has hardened off, it is a good idea to begin your fertilising routine. Which fertiliser should you use? Before I talk about this, let’s cover what plants need in order to thrive.
What Growing Conditions Do Plants Need?
For a plant to be healthy and experience healthy growth, it requires:
- Adequate light – Most herbs and vegetables need 4-6 hours of sun a day. If plants don’t get enough sunlight, it limits photosynthesis. Food reserves will quickly deplete, leaves will turn light green and the plant becomes weak and thin.
- Atmosphere – If its environment is too hot and dry, the soil can dry out. Too wet and mould and mildew can be a problem. It is a good idea to create the right microclimate for your plants for it to be happy. If the weather is drying out your soil, mulch using coir fibre or leaves. This protects the soil from drying out, and can also deter weeds from popping up around your plant. To reduce the likelihood of mildew, look at improving air circulation around your plants.
- Temperature – Every plant has its optimal temperature to thrive. High temperatures can result in heat stress, while excess sun exposure causes leaf burn and sun scald in some plants. If it is a case of too much sun, consider the use of shade cloth. Alternatively, growing sun-loving, vining plants on an overhead trellis to offer shade to your other plants. Bittergourd, luffa, malabar spinach, climbing beans are some options.
- Water supply – Too little and the plant will wilt and may never recover, or plants may be stunted. Leaves may also fall prematurely and produce a poor yield. Similarly, too much water can cause water logging, root rot, depletion of oxygen in soil or edema. Some plants, like pandan, kang kong, or taro are water loving plants, while some others, like okra and sweet potatoes are more drought tolerant.
- Mineral salts – Deficiencies in nitrogen, phosphorus, potassium, magnesium will impair the growth of the plant. It is crucial to feed your plants with fertiliser, also ensuring you feed them trace minerals, which can be derived from seaweed solution.
To get these conditions right, you need to do research on the plants you are planning to grow and what their soil, watering and light requirements are. Plants native to Singapore like our hot and humid climate, but some prefer a bit more shade more than others. This includes ginger and turmeric, which favour light shade.
One popular question is – When should I water my plants and how much? Some people water in the early morning and some prefer to water in the late afternoon because of their schedules. Watering in the morning (before 9am) allows any wet foliage to dry off during the day, minimising risk of fungal diseases. If using drip irrigation or watering at the roots, morning or evening watering doesn’t matter. Mid-afternoon watering is not water-wise, as water will evaporate quickly, I would not encourage this.
If you plan to grow plants that thrive in subtropical or temperate climates, do note that it will be tricky to grow these herbs and vegetables in Singapore. Green leafy vegetables like kale, lettuce and silverbeet will taste bitter and the leaves will be tough if exposed to full day sun. Instead, morning sun or late afternoon sun is best, but if afternoon sun is what you are blessed with, then you will have to consider shade cloth to create conditions that will suit your plant’s preference.
What Kind of Soil Should I Use to Grow Vegetables?
Soils are mainly categorised as clay, loam or sandy and further classified as clay loam or sandy loam, but in general soils contain a mix of clay, loam and sand in varying amounts. It is important to note the soil profile because too much clay and you could have drainage issues, too much sand and you could have nutrients leaching from your soil.
When you visit garden nurseries in Singapore, you will find that they may stock different brands of soil from the others. You will also find terms like garden soil, top soil, volcanic soil, peat soil/moss or potting mix.
Garden soil is meant for direct garden use and is what we would usually associate with earth that we see outdoors. Potting mix is made for container gardening, and is usually soil-less and contains compost or peat moss, plus other soil amendments for better moisture retention and drainage properties. Therefore you will notice that the texture garden soil and potting soil differs. Generally I don’t buy top soil nor volcanic soil because it doesn’t guarantee that I’m getting moist, good quality soil teeming with microbes.
While you are at the garden nursery you will notice other products like burnt earth, which is clay baked at high temperatures, and LECA or Lightweight Expanded Clay Aggregate, a growing substrate commonly seen in hydroponics or aquaculture but also used in gardening for drainage in pots, or perlite, sand, vermiculite, rice husk, among others. More experienced gardeners mix this with soil or potting mix to create soil properties suitable for their plants. So like how you can put together your own seed raising mix, you can do the same with potting mix.
Good drainage is essential, and I’m going to re-emphasise how important it is to know your plants’ preferences. Be sure to do some research before planting / transplanting your new herbs and vegetables into soil.
My personal choice for store-bought soil comes from Greenspade (not a paid promotion), O’Green Living is as good also. Both web-stores also stock a good range of soil amendments that will be helpful in your quest to grow herbs and vegetables in Singapore.
Good soil structure is important – we need to feed the soil to feed the plant. The microbes in soil break down the nutrients for plants to absorb. Which leads me to the topic of plant fertilisation.
How to Fertilise Your Vegetables
Many people are afraid to fertilise in the fear that they will over-fertilise. Don’t worry, as long as you follow the instructions on the packaging, all will be well. If the packet doesn’t come with instructions, you can always look online for suggested fertiliser application rates to grow herbs and vegetables in Singapore.
There are many kinds of fertilisers available on the market. Fertilisers come in liquid and solid forms, from organic or inorganic sources, and can be readily soluble or slow releasing. Which is best for you? It depends on what your plants need and your preference of natural or synthetic fertilisers and whether you prefer to fertilise every week, bi-weekly or once in a long time. Personally, I prefer to use fish emulsion because it is a complete fertiliser but it requires me to fertilise my vegetables every two weeks.
Do note that herbs do not require as much fertiliser as green leafy vegetables, and fruiting vegetables require more fertiliser than green leafy vegetables. Also, herbs and vegetables have different nutrient requirements. For example, tomatoes, eggplant and peppers can develop blossom-end rot if they do have enough calcium. In addition, tomatoes require a lot of potassium for quality fruit and a good crop.
Aside from fish emulsion, which can even be purchased from some supermarkets, other fertilisers you can consider using include aged sheep, cow, horse and chicken manure. These are available for purchase at garden nurseries. Never use your cat or dog’s manure because their waste can contain parasites. This requires composting at high temperatures to kill pathogens. For a list of popular fertilisers that you can buy in Singapore, see here.
Well-composted animal manure can be added to your soil prior to the transplanting process as part of soil preparation, and reapplied every 4-6 weeks afterwards. However, if you are using a soil / potting mix that already contains enough nutrients (according to its label), you need not apply fertiliser till later.
When browsing fertiliser brands you will notice a series of 3 numbers on the label, which resemble 5-5-5 or 6-15-3. This refers to the NPK – Nitrogen, Phosphorus and Potassium – ratio, classified in percentages according to weight. Therefore a 100g bag of 6-15-3 fertiliser contains 6g of N, 15g of P, and 3g of K.
Plants need trace minerals, so depending on the fertiliser you are using, you may need to supplement your plant’s fertilising regimen with seaweed solution. However some fertilisers already contain a mix of the nutrients your plants need so you may not need to add more trace minerals.
Other than fertilisers, we can add soil amendments like compost, worm compost, leaf mould (from composting leaves), potassium sulphate, or bonemeal etc, as soil conditioners for plants. Compost can be used as a soil amendment but do not regard it as a fertiliser because it does not contain as much nutrients as fertilisers. Eventually you will probably want to create your own compost, here are some composting options you can consider.
Where to buy seeds, gardening products and tools in Singapore?
A wonderful one-stop shop for urban farmers in-the-know is World Farm, located in the Yishun/Sembawang area. They stock a lot of gardening essentials, including seeds, pots, waterers, soil, compost and soil amendments, hand spade and other hand tools. They also sell inexpensively-priced herbs, and retail a wide variety of ornamental plants.
If you are looking for a seed supplier in Singapore, you will find an affordable range sold by GreenSpade, World Farm, The Seeds Master and other shops, for a more comprehensive list with a price guide, see here. Carousell is a great platform to procure seeds, just make sure you seek out sellers with good reviews.
For pots, you can check out this resource I have created on buying pots in Singapore. Here, I list the merits of using different types of pots for gardening, and where you can buy them.
Basic gardening tools can be easily found at garden nurseries and even at Daiso. However if you are looking for better quality tools, you can consider Gardena. For top of the line pruning shears, my personal favourite is Felco, and for hand saws, Silky is excellent.
As a beginner, you may wish to get cheaper, basic tools first, and subsequently upgrade to better tools along the way.
Facebook Gardening Communities in Singapore
There are many gardening communities that you can join online and offline to support your learning journey. Swap seeds and plant cuttings, glean advice and gain inspiration from other gardeners via Facebook groups. Some popular ones include Green Culture Singapore, Urban Farmers (Singapore), Singapore Urban Farming and Plant Swap Singapore (SG).
You can also attend Gardener’s Day Out, a regular gardening event organised by NParks, or seek out your nearest community garden to learn more about how to grow vegetables in Singapore.