Growing Japanese Summer Corn in Singapore

Sometime mid-August this year, I scheduled a visit to Kyoto for the annual summer pottery festival and cormorant fishing at Arashiyama. I also wanted to revisit the farming towns along Lake Biwa and try the summer fish that I heard so much about. Enroute up from Kyoto to Lake Biwa, we passed by fields after fields of rice plantations and stopped at a trout farm by the mountains for lunch. These farming practices are a testament to the pristine waters of the Shiga Prefecture.

Since we were visiting the area, I couldn’t pass up a chance to explore the Omihachiman canals. The canals, also known as hachiman-bori used to be an old merchant’s quarter and is known as japan’s Venice. There are many small shops that line the canal.

As mentioned above, Shiga prefecture is known for its quality agricultural produce, since I visited during the summer months when fruits and vegetables are at their peak I made it a point to go to a local farmer’s market. The one we visited is called ‘Omi Green Farmer’s Market’ located near Bakery&Cafe KiKi where we got our morning bread and coffee.

As you can tell the Market was very busy and it sold all sorts of rare and interesting produce like arab okras (small and stubby cousins of the green ladys fingers we have in Singapore, pictured below), white egg plants, pink mushrooms, blue potatoes and a huge variety of pumpkins and squash, some of which are ornamental.

On your right, you can see a man holding what appears to be a stalk of corn that has been cut down with the ear still intact. The cut ends were still moist and white, this clearly evinced the freshness of the corn. Some of you may be familiar with Hokkaido White Corn, popularised by its sweet fruit-like kernels that can be eaten raw (and are sometimes served in high end restaurants as a dessert), but the ones sold at this market were yellow.

I reproduce an extract of an article from Japan Times about corn in Japanese culture:

Sweet corn was first grown domestically in Hokkaido in the 1900s, when the northern island underwent large-scale development as farmland, but it didn’t become widely popular until the 1950s and ’60s. Hokkaido still dominates domestic corn production. Sweet corn is now a familiar and popular vegetable around the country, and fresh corn is a welcome fixture during the summer.

While purists prefer it to be simply boiled in salt water, a very Japanese way of cooking corn on the cob is to boil it briefly and then grill it while brushing the surface with soy sauce or a mixture of soy sauce, mirin and sugar. The nutty, salty flavor of the burned soy sauce is a perfect foil for the sweetness of the corn, and the smell as it cooks is irresistible. Grilled corn on the cob is a regular item at summertime festivals and barbecues.

by Makiko Itoh

Whilst my pops and I were able to try the grilled Japanese summer corn at the farmers market, I was curious to grow the yellow variety in my garden. Thankfully, I only had to go to the florist section to find an array of vegetable seeds, including yellow Japanese corn.


First, plant the seeds in moist loamy soil, that is 3:2:1 of potting soil, compost and rice husk/perlite.

Corn needs at least 4-5 KG of soil and a big pot to grow well.

For reference, I planted my seeds on 14 August in my large vegepod which has a depth of about 30cm.

Relying on whats recorded in my notebook:

By 19 August the corn was 8cm tall; by 23 August it hit 12 cm, on 8 September it was 25 cm, finally reaching 50-60cm by 21 September.

At this stage, the tassels started to grow.

The tassels are the male flowers on the top of the corn stalk that produce pollen. In corn plantations, wind pollination is sufficient for the pollen to reach the female part of the corn (ie the silk).

However, if you are growing corn at a housing corridor, rooftop garden or small-scale in a community garden/farm you will need to manually pollinate for fruit.

From my experience and research, I discovered that the tassels (male part) usually appear 3-4 days before the silk on the ear (female part). Once the tassels appear they will start producing pollen, each branch of tassel will open at different times (staggered blooming for the male corn flowers). Corn pollen is viable for 6 days if stored properly.


With the above timelines in mind, you may now appreciate why corn pollen needs to be collected each time the tassels bloom (because the female sexual organs only appear 3-4 days later). That said, as pictured above, I collected the pollen, dried them in a cool breezy area for 1 hour and stored them in my freezer.

When the silk finally appeared, I carefully sprinkled the stored pollen over all of the silk ensuring that the male gametes are captured. This is an easy step as corn silk is “sticky” and pollen will adhere to it easily.

I then repeated this process 3 times over a span of 3 days.

This picture was taken on 8 October, you can see how well the kernels have developed but this ear of corn is not ready for harvesting.


Sliced corn and corn ‘milk’

Knowing when to harvest your corn is extremely important. Pre-mature harvesting of the ear will yield tough and fibrous kernels that are not good for eating. Here are three ways to tell whether your corn is ripe:

  1. The silk has turned brown or black – the dying back of the silk indicates that pollination has been complete and the kernels are forming;
  2. The kernels are rounded and not pointed at the tip;
  3. The kernels fill the gaps on the cob and give the ear a ‘full’ appearance;
  4. If you press open one kernel it should produce a milky white substance, ‘corn milk’.

WARNING: when the corn becomes ripe, it gives of a sweet smell that attracts many insects and birds, protect your corn by wrapping it with plastic.

Continuing from above, I harvested this batch of corn on 17 October – approximately 2 months after I sowed the seeds.

I was extremely satisfied with this cycle. Not only did the kernels form (almost) completely around the cob, they were also succulent and sweet. Just like the Hokkaido white corn. If I had to give a taste analogy, Id say its akin to a crunchy star apple/milk fruit with a “beany” aftertaste.

I am now moving on to growing multicoloured gem corns. Hopefully they are as successful as this little experiment.

Till then,