Pesticides in Tea
We need “pesticides” to grow tea. Crops are susceptible to diseases and pests, so pesticides are used in cultivation for stable supply. Every crop has a different purpose of using pesticides. This article is about pesticides in the cultivation of tea.
Pesticides that are used for tea
pesticides that are used in tea cultivation are pesticides, fungicides, herbicide, etc. Fungicides are divided into the two types: Protectants for disease protection and therapeutic agents for disease treatment. The use of pesticides, regarding residue standards and the period and method of use, is strictly regulated by Agricultural Chemicals Regulation Act, Food Sanitation Act, Water Pollution Prevention Law, etc.
Diseases of tea
There are several diseases of tea. Infected parts can be fresh buds, leaves, roots, stems, or others depending on the case. While different cultivars are liable to different diseases, common diseases are anthrax, blister blight, Pythium red blight, Dendrophoma obscurans, Pestalotiopsis longiseta, etc. Anthrax in particular can be seen at tea plantations across the country because “Yabukita,” the representative cultivar of tea, is susceptible to it. Pesticides are effective against these diseases to some extent.
Pests of tea
Tea has 100 types of pests. There are so many, but only a dozen or so require control. Major pests include yellow tea thrips, Kanzawa spider mites, tea jassids, tea leaf roller, and white peach scales. Pest damage varies by pest types. Some suck the sap of tea trees, and others eat leaves, especially fresh buds. There is also one that blights stems and branches.
Advantages and disadvantages of Pesticides
The advantages and disadvantages of pesticides are as follows.
Advantages
The basic disease prevention is to grow a disease-resistant cultivar, but it is unlikely that the chosen cultivar also makes large yields of good quality. To cover these shortcomings, farmers use pesticides. In addition, increased weeds take necessary nutrients for the growth of tea trees, so they sprinkle herbicides to prevent the growth of weeds. It also reduces labor for farmers suffering continuous shortage of hands.
Disadvantages
To fulfill the purposes of pesticides, such as killing pests and removing weeds, they need to be violently poisonous. It is not only consumers but also the farmers sprinkling them who worry about health hazards. Furthermore, the use of pesticides is disturbing the ecosystem by acting only on specific pests and weeds, and inevitably causing negative environmental effects. Today’s pesticides are friendlier to the human body and environment than before. However, there are still many challenges.
Fertilizers for Tea
Fertilizer" is used when growing tea.
Appropriate use of fertilizers can make tea aroma and taste to your liking.
In this article, we will explain the types of fertilizers and their merits and demerits in detail.
Fertilizers used for tea
The purpose of fertilizers used for tea is to produce a large harvest of high-quality tea leaves, and the necessary nutrients are applied. This is called "fertilization."
The main components of fertilizer are nitrogen (N), phosphoric acid (P), and potassium (K), which are called the three primary elements of fertilizer.
Since tea leaves are a crop rich in amino acids, nitrogen supply is essential.
Fertilizers can be divided into two main categories: chemical fertilizers and organic fertilizers.
What are the characteristics of each type of fertilizer?
Chemical fertilizers
Chemical fertilizers are made by chemically manipulating components essential for plant growth and increasing their concentration.
There are two types of chemical fertilizers: "simple fertilizers," which are made from single fertilizer components such as nitrogen, phosphate, and potassium, and "chemical compound fertilizers," which are made by mixing these components.
Organic fertilizers
Organic fertilizers are fertilizers made from organic materials such as animal feces and food dregs.
Plant-based fertilizers are made from rapeseed, soybean, etc., and animal-based fertilizers are made from fish, fish, etc. There is also a type of fertilizer called "bokashi fertilizer," in which microorganisms ferment these materials.
Advantages and disadvantages of using fertilizers
The next topic is the advantages and disadvantages of chemical fertilizers and organic fertilizers.
Advantages of chemical fertilizers
Because the fertilizers are separated by component, you can use different types of fertilizers depending on what you want them to act on. In addition, fertilizer management becomes easier because you can choose the type and amount of fertilizer while watching growth.
In particular, since nitrogen determines the umami components of tea, the amount of nitrogen fertilizer can be adjusted to suit the desired umami of the tea.
Disadvantages of chemical fertilizers
Tea plants have a limited amount of fertilizer that they can absorb. Therefore, excessive application of fertilizers can cause tea plants to have trouble absorbing the fertilizers, resulting in lower yields and poor quality.
There are also concerns about the environmental impact of chemically produced fertilizers.
Advantages of organic fertilizers
Because of its high organic content, it provides food for microorganisms living in the soil and stimulates their activity. The products produced by the microorganisms improve the quality of the soil, which in turn enhances the growth of tea plants.
In addition, because the fertilizer is made from organic matter such as food, it is environmentally friendly.
Disadvantages of organic fertilizers
Compared to chemical fertilizers, organic fertilizers do not have an immediate effect, making the timing of fertilizer application more difficult.
Incorrect fertilizer management can delay growth and reduce yields, so constant attention to soil, climate, and growth conditions are necessary to manage fertilizers.
Covered / Shaded Cultivation of Tea
“Cover cultivation” is one of the tea cultivation methods. Tea leaves grown in this method are processed into “Gyokuro,” “Tencha,” and “Kabusecha.” Why are tea leaves grown in cover cultivation preferred to make these types of tea? This article provides the reason in detail.
What is cover cultivation?
Cover cultivation is a cultivation method in which tea trees with growing fresh buds are covered to avoid sunlight for a certain period. Photosynthesis in the leaf barely happens without the sun, so the fresh buds take a longer time to grow to become harder leaves. Picking time can be longer thanks to this process. In addition, the cover keeps the leaves warm so that they can be protected against frost and picked earlier. Good-quality tea is produced from the leaves that are “less hard and kept warm.”
Features of tea grown in cover cultivation
A tea leaf covered during cultivation takes on a distinctive grassy aroma called “ooika (literally cover aroma in Japanese).” An increased number of chlorophylls deepen the green color of the leaf.
The tea grown by cover cultivation has a bright green liquid color compared with the tea produced without covering. Its characteristic rich fragrance arising from the cover aroma and slightly astringent flavor entertains you well. The brilliant tint and light astringency are suited for the processing of “Gyokuro” and “Tencha”
Why does cover cultivation make tea more delicious?
The tea’s umami component theanine, when exposed to the sun, changes to the tea’s astringent component catechin. However, cover cultivation blocks sunlight and prevents theanine from changing to catechin, so the tea can store full of umami. Furthermore, the amount of caffeine, which is less bitter than catechin, increases by light shielding. As a result, the tea grown by cover cultivation provides a sweeter flavor with lighter astringency and bitterness than the tea grown without covering.
Organic Farming of Tea
"Organic cultivation" is one of the methods of tea cultivation.
Do you know what organic cultivation is? Strict standards must be met before tea can be labeled as organically grown. In this article, we will explain in detail about organic farming.
What is organic farming?
Organic farming uses methods that "do not use chemically synthesized fertilizers or pesticides, do not use genetic modification technology, and reduce the environmental impact of agricultural production as much as possible."
Specifically, it refers to cultivation methods that do not use prohibited pesticides or chemical fertilizers and that take into consideration nature's natural ecosystems.
There is also pesticide-free cultivation, but it is not the same as organic cultivation because the regulations differ. Organic cultivation is subject to strict standards, not only in terms of whether or not pesticides are applied but also in terms of soil preparation and seed suppliers.
JAS Certification
JAS certification is given to agricultural products and processed foods that meet the standards for organic cultivation.
Based on the JAS Law established by the Minister of Agriculture, Forestry, and Fisheries, a registered certifying organization conducts inspections. Only products that pass these inspections are allowed to be labeled "organic" or "organically grown.
When applying the JAS mark, the name of the inspection organization that conducted the inspection and the certification number must be indicated.
Organic Farming of Tea
Organic tea must be harvested from areas free of synthetic pesticides, synthetic fertilizers, and synthetic soil conditioners for at least three years and where the soil has been prepared with compost or other fertilizers.
If fertilizers are used, only organic fertilizers that meet the standards may be used. When organic farmers use fertilizers, they mainly use homemade fertilizers (fermented fertilizers).
During cultivation, farmers take the time and effort to harvest leaves appropriately to prevent a sudden increase in insects and diseases and to cut weeds to ensure that the tea plants are well nourished.
Features of Organic Tea
Because the tea leaves are grown in a near-wild state, the original flavor of the tea leaves is brought out to the maximum extent.
Although the aroma is strong, the bitterness and astringency are not too strong, and the tea has a moderate richness and a refreshing aftertaste.
Advantages
When usual tea leaves are brewed in hot or cold water, agrochemicals also melt into the liquid.
Even though the amount is safe to our body, there are concerns about consuming agrochemicals for many years.
However, organically grown tea leaves are completely free of such concerns, and can be consumed safely even by those with chemical sensitivities.
In addition, by not using pesticides in cultivation, the tea is environmentally friendly and does not negatively impact the ecosystem. Therefore, it is expected to help maintain and stabilize agriculture in the future.However, organically grown tea leaves are completely free of such concerns, and can be consumed safely even by those with chemical sensitivities.
In addition, by not using pesticides in cultivation, the tea is environmentally friendly and does not negatively impact the ecosystem. Therefore, it is expected to help maintain and stabilize agriculture in the future.
Disadvantages
In the early stages of conversion to organic farming, yields are unstable due to many pests and diseases.
Organic fertilizers are also challenging to handle, and their ingredients are less stable than chemical fertilizers, so you must constantly assess the condition of the soil and crops to manage fertilizers.
Because the tea plant is more susceptible to crop failure due to weather conditions and adverse effects of pests and diseases, it isn't easy to achieve stable production year after year in terms of yield and quality.
Without knowledge and skill and a long period of time for the soil to stabilize, obtaining stable yields with organic farming isn't easy.
Another disadvantage is that because herbicides are not used, weeding is required throughout the year to remove weeds that have grown between the rows, increasing the workload for farmers.