Considerations on grape cultivation in Hida②-2021

Based on the above, if we assume that there is almost no difference in appearance due to training, then we will consider what training method will provide optimal canopy management.

-Hida grape cultivation (hedge cultivation)-

When it comes to grape quality, there are various indicators such as fruit concentration, soundness, and sugar content, but at least when it comes to fruit soundness (few diseases), I think that hedge cultivation is not very suitable for rainy areas, including Hida. (The grape-producing areas are different because the environment is good. The European training method is still in place.) First of all, in a hedge, new shoots tend to overlap and humidity tends to be high, making it easy for diseases to occur. To overcome this, it is important to reduce the density of new shoots and prevent overcrowding.

"Two Ways"
1. Limiting the number of new shoots: Thoroughly thin out shoots in hedge cultivation to prevent new shoots from growing too close together. This reduces the yield per unit length. If the spacing between plants is too narrow, it may be difficult to control the tree vigor.
2. Using the lilac method: A method of cultivating two closely spaced hedge rows from a single tree. Compared to hedges, even if the shoot density is lowered, the number of shoots per unit length can be increased, making it easier to control the tree's vigor and ensure a good yield. However, construction and labor costs are higher than with hedge cultivation.

The difficulty in areas with a lot of rain is that the trees become stronger. To succeed in hedge cultivation, the new shoot density must be lower than in the production area, but this means a decrease in yield and stronger tree vigor. Fruit size is greatly affected by the tree vigor, so if the tree vigor becomes strong despite the adoption of hedge cultivation to produce small fruits, it will be a waste. Most wine grape varieties are basically susceptible to disease. If pesticide spraying is thorough, the new shoot density can be controlled to a certain extent, even if it is high, but from the perspective of reducing the use of pesticides, creating a high density around the fruit is questionable. Some people may say that it would be fine to protect the fruit from the rain with plastic, but at the same time, this will also warm the area around the fruit. (The same thing can happen as when apples are covered with a bag to make them look better, and the flavor becomes dull. Wine grapes are grapes for processing after all. The taste cannot compete with outdoor cultivation.) It's fine to use an umbrella that allows air to pass through, but if you are going to use plastic, you may want to change the training method or variety. Additionally, cultivation management requires working in a low position, making it a very taxing method of cultivation. However, there are benefits. If you are looking for truly high-quality grapes, you can suppress the size of the fruit by planting them closely together to suppress the vigor of the trees and allow the new shoots to stand up. Even in Hida, if the fields have weak soil fertility, it may be possible to suppress the overgrowth of weeds and still produce high-quality fruit. This is a task that remains to be done, but there is no doubt that it will be a difficult challenge.

-Hida grape cultivation (new short-shoot cultivation)-

　The most promising method is the new short shoot cultivation. This method was invented by Takao Ogawa, who was a fruit tree extension worker in Yamanashi Prefecture, and is a derivative of the short shoot cultivation. One of Ogawa's disciples showed me a grape vineyard for eating fresh, and I thought it was a very sophisticated cultivation system. By training the new shoots in a Y shape, the bunches are arranged in a row at eye level, which not only makes it easier to work with, but also makes it easier to spray chemicals with a speed sprayer. Since the tips of the new shoots are trained to be horizontal to the ground, the furrows are often wide apart, and the number of new shoots per unit area tends to be lower than with a hedge, but since ventilation is good and the health of the fruit can be guaranteed, I believe that the yield is equal to or greater than that of a hedge. Also, from the perspective of labor productivity, it is easy to work with, and I even think that there is no better method. It is true that if harvesting could be mechanized with hedge cultivation like in other countries, productivity may be high. However, harvesting machines weigh around 10 tons, and as they harden the fields and damage the trees, there are no longer any places in Japan that use machines for harvesting (except for AI robots). I think this will become the mainstream cultivation method in the future, except in areas such as Hokkaido where the trunks will be damaged by frost if they are not kept under the snow. What do you think?

The history of wine in Japan is short, and cultivation methods have not yet been established, so it is undoubtedly more difficult outside of the wine-producing areas. Because the methods are not established in a sense, it is tempting to turn to hedge cultivation, which has been successful in the wine-producing areas, but when it comes to apple cultivation in Hida, even if you follow the methods used in producing areas such as Nagano, it often does not work well due to the difference in precipitation.

We will continue to experiment every day as we work towards launching Hida Wine.

If you are reading this, you must have some time. Let's make wine together in Hida!