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Tea Plantations

CULTIVATION OF GREEN TEA FROM PLANTING TO THE FINAL PRODUCT

 

THE START

In order to achieve favorable harvesting conditions, the tree is kept small, they are cultivated like shrubs. that means the tea tree usually reaches a height of about 1-2 meters. However, it should be noted that under the right circumstances the tea tree can reach a height of up to 15 meters at high altitudes, in well drained soils.

But because of the looks of the plant, most people speak of a bush but in fact, it’s a tree.

Nowadays two methods are used to cultivate plants. According to the less common method, the traditional one, the seeds are pre-germinated under moist jute fabric and then allowed to grow. Today the vegetative method, with which seedlings are grown, is used almost exclusively. This allows a constant plant quality, because the plant could adapt to the environmental conditions over centuries.

The life of every tea tree starts as a seedling. Spring around March, April is the common planting time for seedlings. After around 4 years the tree is ready for the first harvest. But only after around 5 to 8 years, the leaves and buds are enriched and the harvest and quality are stabilized.

But before we can harvest there is a lot of work to be done. For example, the cutting starts around two years after planting the trees. Not in order to control the height of the tea plant, rather to promote the growth of side branches, and expand the picking surface in an early stage. Additionally, weeds can grow between the young tea plants. Therefore, often a vinyl sheet or straw is laid down to cover the ground and prevent weeds from growing.

Tea Tree

Recent planted samidori seedling

SUNLIGHT OR NO SUNLIGHT

In Japan there are basically two methods of growing green tea, which differ in how much sunlight the leaves are exposed to.

  • Rotenen (tea plantations without covers)

  • Oishitaen (tea plantations with cover)

 

The amount of sunlight makes a mild tea with a lot of umami or a refreshing tea with slight astringency. Tea leaves contain a protein called L-Theanine, which creates the Umami taste.

This substance is created in the roots of the tea plant and travels to the leaves. Exposed to sunlight this substance turns in to Catechin which causes astringency.

 

Rotenen

The tea plants get full sunlight exposure, so the leaves grow under natural conditions. This kind of production is used to create for example Sencha, Bancha or Genmaicha Green Tea.

 

Oishitaen

As the new buds start to appear around mid-April the tea plants are being covered with reed screens, straw or man-made fiber cloths to avoid direct sunlight. No direct sunlight means that the L-Theanine is prevented from turning into Catechin in the leaves, what gives the tea more of an Umami taste. This method is used to create Gyokuro, Tencha (Matcha) and Kabusecha.

 

There are basically two types of shading to make tea with the oishitaen method

  • Canopy Covering

  • Direct Covering

 

Canopy Covering

With this method, normally premium Gyokuro and Tencha (Matcha) is made. This method is more time-consuming than the direct covering method but gives you the opportunity of adjusting the amount of sunlight reaching the leaves.

Traditional Canopy Covering

In the front traditional canopy covered tea fields and in the background cheesecloth canopy covered tea firlds

Traditional canopy covering:

This method uses natural materials and has its origins in protection young sprouted tea leaves from late frost. The use of natural materials has several benefits like the possibility for the tea plants to breathe due to an air- and wind-permeable construction.

Everything starts in spring, when new tea buds begin to sprout, the whole tea field is then covered with bamboo-reed blinds. With this first step around 60% to 70% of the sunlight is blocked. After this initial shading step, approximately 7 to 10 days later, the final part of shading takes place. A wealthy amount of firmly dried rice straw is dispersed on top of the bamboo-reed blinds. The tee plants are now almost in complete darkness, around 95-98% of the sunlight is blocked to inhibit almost all photosynthesis. After around an overall period of around 20 to 25 days, the leaves are then ready to be harvested and further processed.

 

Cheesecloth canopy covering

The traditional way of covering tea fields is rather labor intensive, what opens the door for more economical ways of shading the tea plants. One of these rather less labor-intensive ways of covering is the use of black cheesecloth made of synthetic fibers. The application of cheesecloth canopy is very similar to the traditional canopy covering using bamboo-reeds and straw. After the first leaves start to unfold a first layer of cheesecloth is used to block the sunlight. Then after a bit more than a week, the second layer of cheesecloth is used to block almost 100% of the sunlight, so the leaves can grow almost in the complete darkness for up to 20 to 25 days overall.

Tea Plantations

Tea plantation with direct covered tea plants for Kabusecha

Direct Covering

When using this method, the cloth - usually a cheesecloth - is applied immediately on top of the plants. With this method manly Kabusecha is made as well as lower grade Gyokuro, Tencha and recently Sencha. The covering time, usually around 10 days, is not as long as with canopy shading, but can be extended to up to 20 days. This method is the least time consuming and most economical shading method contemporarily in use for the cultivation of tea. Usually Japanese tea farmers us a black plastic material for this type of shading. But there are also other materials in use which give other benefits such as increasing the temperature around the plants. The downside with this method is that because the cloth is directly applied on the leaves, the leaves can get damaged because the shading material can flap against the leaves in the wind. and in addition, the amount of sunlight cannot be adjusted with this shading method.

 

Overall, the traditional method of shading is almost exclusively used for premium Gyokuro and Tencha (Matcha), due to a better taste of tea and more labor-intensive application. The new approach of shading, using synthetic materials is used for high grade Gyokuro and Tencha (Matcha) to serve a wider market due the economic benefits.

Harvest

Depending on the region in Japan and weather conditions, tea leaves are ready for harvest at a slightly different time every year. In Uji the tea harvest starts usually at the end of April with Sencha and is followed by Gyokuro and Tencha (Matcha). In Japan, depending on the region, the tea leaves are harvested up to four times a year. The first harvest of the year, usually called Shincha, is in terms of quality known as the best tea of the year. Shincha is often referred as first flush tea or “Ichibancha”. As can be assumed tea leaves were picked usually by hand and only after World War II in the period known as “Japanese economic miracle”, the first usage of machinery in the tea harvest took place. Until this time tea bushes didn’t require a special shape, the usage of machines made it necessary to form them for this sole purpose. Today most tea produced in Japan is made out machine trimmed tea leaves, but there is still a demand for hand-picked leaves. Usually the leaves picked by hand tend to have a much more mellow taste and are generally seen to give a smoother tea than machine trimmed leaves give. Hand-picked leaves are much more precious and are only used for superior tea.

 

Today, in Japan there are three main ways of harvesting the tea leaves. Which differ in the amount of the leaves which can be picked and the quality output of the leaves.

Tea Picking

Tencha leaves are being picked by hand

Handpicked harvest (1-3 kg/h)

The leaves are picked according to three different methods. The output, compared to other methods, is very small but the quality makes it worth it. From the time the sprouts start to appear to the time the leaves become too large to harvest, the tea leaves must be harvested as quickly as possible in one long stretch. Only with the use of skilled hands it is possible to pick a larger amount of leaves in the picking period which only lasts a few days. Tea picking usually takes place in the early morning until dawn and is performed by well experienced tea pickers. To pick a suitable amount of good sprouts a day, this long experience is required.

The best-known picking method is the “1 bud with 2 leaves” method: Leaves are picked from the tip of the stem to the first pair of leaves. Only the finest quality tea is made with this method.

 

Unlike the traditional picking method, automated harvest requires an even, oval shape of the tea fields. A machine has to cut the leaves at a certain height to be efficient. Therefore in spring, before the harvest, the fields are pruned to set the necessary height. Once the harvest has started the now newly appeared fresh buds, which have grown above this height, are now mowed to approximately the same height set in early spring.

Tea Harvest

Half-automated machine harvest on a Sencha tea 

Half-automated machine harvest (300-400 kg/h)

Done with two people, the output is significantly higher than even using skilled hands for picking the leaves.

Half automated machine harvest takes place using a portable harvester. Two people are required to operate the machine efficiently and if possible, a third is required to hold the bag into which the tea leaves are collected. The downside is that the significant increase in efficiency comes with a lower quality of the harvested leaves. This method applies for higher grade green tea.

Tea Plantations

Tea plantation with direct covered tea plants for Kabusecha

Fully automated machine harvest (600-800 kg/h)

The most efficient way of harvesting tea leaves in Japan is the use of tractor harvest machine. The tractor is