Growing Chye Sim (Cai Xin) at Home

Cai Xin, Chye Sim, Choi Sum, Yu Choy, or Chinese Flowering Cabbage are 5 out of the gazillion ways this vegetable familiar to most Asian palettes can be called. Known for its soft and tender texture, this is a common household vegetable that cooks easily – blanched and tossed in oyster sauce and garlic oil, fried with aromatics like garlic or ginger, or simply cooked in a noodle soup. This green leafy vegetable, similar to Kai Lan (Chinese Broccoli), is often characterized by the distinct yellow flowers which it bears.

Chye Sim from super market

For its soft texture and ease of digestibility, Cai Xin is often a choice pick for young and old palettes. Packed with nutrition, easy to grow and cook (cooks in soups within 2 – 3 minutes), pleasant in taste – It is no wonder that this vegetable is a highly recommended choice of grow amongst growers..

Wanton Mee With Chye Sim
Boiled Chye Sim with Soya Sauce

Similar to Bayam (Chinese Spinach), Cai Xin is also grown for both its green and purple (some call it red) varieties. Slightly tougher to get in the market is the purple variety of Cai Xin, so it is a great find if you ever get your hands on it. However, if you do not want to chance upon it, then perhaps growing some in your garden would be the best way to ensure you get your hands on this lovely variety of the Cai Xin family! This vegetable is rich in Folic Acid (also known as Vit B9) which is commonly required for almost every function within the body, so it would be wise to make this vegetable a staple in your meals.

How to grow from seed?

Chye Sim Seeds

As with germinating most leafy vegetables, use either a seedling starter tray or an old egg shell tray to get your Cai Xin seeds going!

*Optional step: Soak seeds overnight (or at least 4 hours) to encourage germination.

Using a seedling tray (a ready made one, or a recycled egg tray), fill the seedling tray with fresh soil potting mix or peat moss (which is soft, fluffy, and holds good amounts of moisture to germinate seeds). Do remember to create holes at the base of each cell for proper water drainage. You can do so by using a pair of kitchen scissors to snip off a small corner of the base of the egg tray – do so for each cell in the tray.

Afterwhich, fill each cell with fresh soil mix, and moisten the soil with a generous amount of water. Then, make a hole (about 1 cm deep) in the soil of each cell to place 1 to 2 seeds into it. Thereafter, you can either sprinkle a thin layer of soil mix over to cover the inserted seeds, or simply “bury” inserted seeds into the soil by lightly patting soil over exposed seeds. Continue to water the mix until it is substantially moist.

Expose the sowed seeds to at least 4 hrs of direct sunlight daily and protect it from rain. As these seeds are small and light-weighted, falling rain or too much water in the plot can easily dislodge the seeds from their sowed spots. Therefore, in the first few days of germination, it is critical to protect the seeds from too much external motion. Cai Xin seeds should take approximately 3 to 5 days to germinate.

After the seedlings have produced 2 – 3 pairs of leaves, they can be transplanted to larger pots or planting plots, preferably in a sunny location.

Soil types for optimal growth:

As with most vegetables, Cai Xin thrive optimally in fertile, loose and well-drained soil with good water retention. For optimal plant nutrition, add compost and/or mulch occasionally to replenish nutrient levels in soil; or apply a small amount of organic fertiliser every 1-2 weeks for optimal growth.

Growing chye Sim in Singapore
Growing Chye Sim in Singapore

With edible vegetables, you would always want to make sure the fertiliser used is preferably organic, and surely food safe. Most plants and vegetables need supplies of nitrogen (N), phosphorus (P) and potassium (K), commonly known as NPK for short, to maintain healthy plant growth. Please also be forewarned that fertilisers must be applied to the plants with an optimal frequency. It may be intuitive to think that a heavier application of fertilizer is better for the plant growth, however in this case, the frequency at which the fertiliser is being applied and the quantity of each application are KEY! Over- application of fertiliser to your plants and vegetables can make the soil “too salty” OR “too concentrated” with fertiliser that the leaves might begin to shrivell.

As with each plant, there are optimal pH levels that will promote optimal growth. Nitrogen (N) present in most fertilisers is the main nutrient affecting and altering soil pH – that is to say, soils can become more acidic or more alkaline depending on the type of nitrogen fertilizer used. Therefore, with fertilisers, it is wise to always err on under-application rather than over-application in order that the soil does not significantly alter in its pH veering away from its optimal pH (which one may already have “tuned” the soil to be).

Optimal PH:

5.8 – 7.0

Sunlight exposure:

Chinese spinach (bayam) plants once germinated need plenty of sunlight (more than the 4 hours of sunlight required in the germination stage). For mature plants, you would be looking at providing at the very least 6 hours of sunlight to the plant.

Watering:

While germinating, keep soil moist – not over soaking in water such that seeds dislodge from their sowed spots; or over soak, soften and rot (die). If you find it hard to remember to water your plants consistently, it is highly recommended that you plant your vegetables in a self-water grow box, which would require you to top up water every 1-2 weeks depending on how hot the weather has been. On hotter days, water gets evaporated faster, therefore requiring more frequent water replenishments; and vice-versa.

After seeds have germinated, go ahead and water plenty! Water good amounts of water – Cai Xin thrives in the moisture!

Positioning:

By the window where plenty of sunlight is available would be a good spot to position your plant.

If not, any other positions that receive good amounts of sunlight (especially morning sunlight) can work too – HDB corridors, balcony, verandas, etc.

Harvesting:

Depending on how tender you like your vegetables to be, you can begin harvesting them as soon as they are 15 cm tall. Growing them longer would give them a chance to develop in size, however the compromise is in the texture of the vegetable – the longer you grow them the more fibrous they become.