Shade growing: why cover matcha green tea leaves?

You may have noticed that the tea fields in my videos are sometimes covered with black or silver nets. In this item, I will show you what tea shading is used for, what its effects are, and what techniques farmers use.

The tea is shaded during the production of tencha, which is an essential step.

Tencha is the word used to describe the state of tea before it is ground into a fine powder, i.e., matcha. If the leaves of the plant from which matcha is extracted, Camellia sinensis (the tea plant), have been properly shaded to produce matcha, then it is called tencha.

What is shaded culture? Why shaded growing of green tea?

At the beginning of April, the tea plants are covered for about twenty days before harvesting, which usually takes place in May. This method produces what is known as "shade-grown tea."

The aim is to gradually reduce their exposure to sunlight and prevent photosynthesis. Very high-quality matcha is immersed in almost total darkness before harvesting.

In this state,the plant must draw almost all of its energy from the soil, as up to 90% less sunlight reaches it.The quality of the soil and terroirare therefore extremely important at this stage because if conditions are poor, the tea plant can weaken and the harvest will be of lower quality.

It is even more difficult in the context of organic or natural production: since the use of fertilizers is prohibited, tea plants must rely on energy from the soil and the little photosynthesis generated.

Tea plants produce excess chlorophyll so they can realise photosynthesis in the dark. It is this high concentration of chlorophyll that gives tea leaves their vibrant, intense green color.

Look at the difference in colour between shade-grown tea leaves (left) and those exposed to the sun (right):

We can see that the green is much deeper and more powerful on the row of tea plants that have been shaded.

Doctors and researchers claim that chlorophyll is one of the most powerful blood detoxifiers and a significant ally in creating ideal blood alkalinity.

To learn more, I recommend this item on the health benefits of matcha tea.

One of the key functions of shaded areas is that the absence of sunlight causes the plant to create new shoots and leaves whose mission is to "seek out the sun."

In this temporary state of lack of sunlight created by shading techniques, the tea plant draws its energy from the earth, changes its chemical composition (with more chlorophyll), and brings as many nutrients and energy as possible to its new shoots to help them in their mission.

These young shoots and leaves, very delicate and full of vitality, are harvested by farmers to be transformed into tencha, then into matcha!

How does shade affect the flavour of matcha tea?

Shading is based on two phenomena that occur when the tea plant is exposed to the sun, changing both the composition of the leaves and their taste.

1. When the tea plant is exposed to sunlight, it produces catechins, powerful antioxidants. Catechins are responsible for the bitter flavour in tea.

2. On the contrary, when tea is covered, it produces more L-theanine. This is an amino acid that combats physical and mental stress and has a relaxing effect. It gives matcha tea its delicious umami flavour.

Umami is a flavour, like the other four basic flavours: sweet, salty, sour, and bitter. It is widely appreciated and sought after in high-quality matcha teas.

Matcha tea is produced from tea leaves that are first exposed to the sun before being covered. It therefore contains a mixture of catechins and L-theanine.

An inexpensive organic matcha tea, such as our organic culinary matcha from Japan, generally has slightly more antioxidant power because it contains slightly more catechins. Since it contains less L-theanine, it will have less umami and less of a soothing and calming effect. A matcha that is high in catechins will also taste more bitter.

In short, it is the shade of the tea plants that gives matcha its smooth and delicious taste, with a balance between bitterness and umami.

The different types of covers

Nowadays, there are different types of shade chosen according to the type of tea the farmer wants to obtain, as well as their financial means and material constraints.

For matcha tea, there are two main categories of shaded areas:

Straw shading: the oldest technique

Here is an example of a farmer who uses rice straw to cover some of his tea gardens.

Click on the play button to view my explanation about straw covers (1min09)

Plastic mulch: much more practical and economical

Here is a concrete example of tea being harvested by hand under black mulch shade:

Click on the play button to view the harvest of tea plants covered with black mulch (5min26).

You can view that it is often older women who harvest the tea. It is seasonal labour in Japan.

There are several shade structures that use these black tarps. They are often placed directly over the tea, which is the simplest technique, but can sometimes damage the leaves.

Or they can be placed on metal hoops. In this case, the leaves breathe better and are protected from contact with the net:

Click on the play button to view the difference with the previous shaded areas (3min14)

Other tea gardens are covered by elaborate structures with pillars that allow air to circulate, as seen here:

Another example of covers from our partner farmer Nishi-san

Click on the play button to view Nishi-san's special covers (5min13)

Nishi-san is the farmer who produces our best organic matcha teas: ultra-premium organic matcha and hyper-premium organic matcha.

These teas are so exceptional and high-quality because Nishi-san is constantly searching for new ways to push the boundaries to produce the best organic matcha tea in the world.

Nishi-san chose to use silver covers that reflect the sun's rays and keep the tea plants cool in order to achieve such high quality.

The quality of tea, its taste, and its concentration of antioxidants and L-theanine vary from year to year depending on a multitude of factors. And it is thanks to Nishi-san's expertise that we can enjoy matcha tea with such a rich and complex taste.

Choosing the right time to cover or harvest the tea is also a major challenge: covering the tea plants for too long can damage them and jeopardize a whole year's labour (or more). It takes years of experience to learn all the subtle aspects that go into making excellent matcha tea.

I am so happy that our community supports these talented farmers.

Let me know if you have any questions, feedback, or would like detailed explanations on other themes, and I'll get back to you in the comments below!

- Val de Kumiko Matcha

=> Get a 10% discount on your first purchase of organic matcha with the code KUMIKO10!