For The Love of Mangos Japan Expedition 2013

Mangos in the Snow

Noris Ledesma, Curator of Tropical Fruit

 

The art and adaptation of the mango have taken our Florida mangos to new frontiers. The Japanese have been growing Miami’s very own ‘Irwin’ since the 1980s under glass in heated greenhouses at north latitudes equivalent to central Minnesota. It is a long way, both in distance and mind set from northwest Miami – home of the ‘Irwin’ – to the temperate forests of Saporo, north Japan. Yet, here it grows, in such a small space, adapted by the Japanese grower to their needs. Just as the art of bonsai was brought to Japan by Chinese monks looking to expand their religion into the kingdom of Japanese, the modern Japanese growers use highly detailed pruning and shaping of the mango to gain acceptance of the mango as a fruit of the Nobles.

This was my second trip to Japan and this opportunity I was invited as a guest speaker at the Fruit Growers Association meeting held in Miyazaki.  More than 100 mango growers attended the meeting and my role was to give advice on new cultivars for the Japanese market.

I was still filled with good memories from my first visit to Japan in 2009, where I had the opportunity to see the history of ‘Irwin’ grown on the southern Japanese Island of Okinawa. Okinawa is comprised of 150 islands, where farming is molded to its subtropical climate, which is a little cooler than our winter in South Florida. Okinawa is located in the Temperate Zone and has four seasons. The annual precipitation is over 2,000 mm, and during the winter, the temperature can drop to zero or below. That is the reason mangos are in greenhouses to protect the trees from heavy rains and cold. I met in that time one of the pioneer mango growers in Okinawa, who was an immigrant from Taiwan and brought the seeds that are still used today. They keep using them as a rootstock. He was a master pruner and his 30 year old mangos have been pruned every year, removing wood to rejuvenate the canopy and have more points for production.  In Okinawa they do not induce blooming, as it occurs naturally during the cool winter season.

By 2009, the annual production in Japan was about 1,460 MT per year, and has increased by 50%, through the use of modern and innovative agricultural techniques that allow them to grow mangos in the snow in places like Soporo in the north of Japan.

Dr. John Yonemoto, a long-time friend of Fairchild Garden, also extended an invitation to Soporo to see his mango operation. Here I am in Soporo, picking mangos in the snow!

The temperature in Soporo, was 4C below zero.Traditional growers leaves two principal branches horizontaly to support the canopy for the rest of their life. This will provide light in the most eficient way acording with him. We had a long discussion about mango managment. The harvest season is in June and the average wholesale price of mangos at the Okinawa central wholesale market is 100 yen/kg.

I really enjoyed this visit to see for myself how the Japanese have been domesticated Florida mangos according with their tradition and cultureultural crops include sugar cane, vegetables, flowers and fruits. Mangoes were introduced to Okinawa in the early 1900s, and since the technique for mango production using plastic greenhouses was established, mango production has been increasing year by year. Recently, mangos have become an important part of the Okinawan horticulture industry. The current mango production in Okinawa is about 1460 MT per year. I thought to myself that this was not mango weather when he told me to be ready in the morning for mango picking. It was dark and gloomy and snow was expected in the morning. I spent the night at his house and his lovely wife prepared dinner for us.  In the morning, we walked to the greenhouses and went from a brisk 2C outside to a balmy 35C inside, where the heaters were running all the time.  This is mango season in Soporo. They spend $200,000 a year to heat one greenhouse on1/4 acre.

Mangoes are usually harvested from spring through summer in Japan. But they learned how to produce mangos for Christmas when they can get a premium price. Dr. Yonemoto explained to me his research, based on limiting the root system, pruning and training trees from an early age, solar radiation, and temperature.

 Limiting the root system can be done by growing trees in containers, or by burying non-woven fabric to limit the root system before greenhouse construction and planting. Planting density is 120 to 240 trees per 1,000 square meters. The first year is spent preparing the rootstock; second or third year in grafting and growing the tree.  By year five, trees are harvested for the first time.  In the 7th year, the targeted value of production is 2000 kg / 1000 square meters.  

The Japanese are making a mango bonsai of sorts; mango trees that exhibit their nature within a limited growing space.  To accomplish this, the mangos trees are carefully pruned every year, removing wood to rejuvenate the canopy and have more points of production.  

He leaves two principal branches horizontally to support the canopy for the rest of their life.  This will provide light in the most efficient way. They still have many challenges such as thrips and anthracnose in the greenhouses.

Dr. Yonemoto has divided the greenhouses into two different groups to control environmental conditions to have two mango seasons, one during the summer and the other for Christmas. He increases photosynthesis by applying carbon dioxide in the enclosed greenhouse environment. He also is embedding piping underground to run cold snow melt water during the summer months, and water from the hot springs in the fall and winter. Although controlling the temperature remains a challenge, they believe that it is ideal to grow mangos through the use of local natural energy resources and an abundance of sunlight.

 

He uses honeybees for pollination. Each box contains approximately 12,000 bees. Besides honeybees, Dr. Yonemoto also uses flies for pollination; they are cheaper but less effective.  Flies have a shorter flight distance and less efficiency than bees. They are not actually beekeepers; they purchase the hives every season and reuse the survivors for next season. In Soporo there is limited sunlight available.  

Dr. Yonemoto uses a creative way to increase light. A white square of paper will do the trick. In order to attain a full red color they carefully expose the fruit to the sunlight until they get full ripeness and they can be harvested. The target is to get 100% red color that brings the premium price. These are techniques we have developed for cultivating delicious and beautiful mangos. Labor is very intensive, and the dedication and detailed effort are impressive. They wait until the mango drops into a net, and farmers harvest fruit as soon as possible to prevent injuries. Every fruit it's evaluated before going to the packing house.

Every single fruit is carefully wrapped and transported to the packing house. Quality control determines the rate of fruit to specific market. The sorting machine they use in the packing house has an infrared scanner to measure sugar content and select color, as well as pulp consistency to assure quality of the fruit.  It's an expensive machine and capacity is very low. But high quality! The machine sorts 1,500 fruit a day and costs about $500,000.

 

Mangos at the Central wholesale market are 100 yen/kg. Look at this, 2 mangos for $180.00 in Tokyo. The local mangos in Japan are very expensive, but they satisfy urban consumers by replacing the low quality imported fruit.  Mango varieties from all over the world reach Japan. The most prevalent variety is Carabao from the Philippines. Tommy Atkins comes from Mexico, and Nan-Doc-Mai from Thailand. 

Why Irwin?  I asked them. They said we love fruit that are juicy, fresh and fully ripe. The Irwin cultivar is juicy with a sweet aroma. Irwin mangos can be harvested when fully ripe. In their experience, Irwin is the only mango which naturally falls from the tree when fully ripened.  Dr. Yonemoto is testing other cultivars. I had an opportunity to see some of the trees he brought from Fairchild’s collections years ago, including Nam Doc Mai, Rapoza, Lippens, Mallika, and our Turpentine as a rootstock. He is also growing avocados, sugar apple, persimmon, passion fruit, dragon fruit, bananas, and carambola.

We flew to Miyzaki from Soporo to meet the growers at the conference.  In the morning we all went on a field trip to visit a mango farm. Miyazaki city is situated at latitude 32 degrees north. Winter in Miyazaki is cold, and minimum temperatures in December and January can be as low as 2C and sometimes there is snow during the winter. Mango production in Miyazaki started in 1986. At present, the total cultivation area for mangos is more than 55 hectare. The volume of production is 700 tons. This value includes young groves whose volume of production is 13 tons per hectares.

 

Mr. Kazunori Yokoyama is showing us his farm to share his secrets on how he can produce more than 10% the top quality mangos in Japan "the egg of the sun". He works with his family, no workers. Their main production is based on the variety 'Irwin', like the rest of the people in Japan. The rootstocks used are a polyembrionic type from Taiwan. Some of traditional growers do not induce blooming, as it occurs naturally during the winter. Mr. Kazunori is developing a protocol to synchronize blooming by pruning, low the temperature, heating soil, and water stress. He sprays phosphorus to decrease nitrogen for the trees to slow down for blooming.  The terminal leaves are stripped five inches from the bud tip to synchronize blooming.  

l winter season. Trees are heavily mulched and intensely managed by pruning. Traditional growers leaves two principal branches horizontaly to support the canopy for the rest of their life. This will provide light in the most eficient way acording with him. We had a long discussion about mango managment. The harvest season is in June and the average wholesale price of mangos at the Okinawa central wholesale market is 100 yen/kg. I really enjoyed this visit to see for myself how the Japanese have been domesticated Florida mangos according with their tradition and culture.They heat the water for irrigation, and control growth temperature to induce blooming as well.

My visit to Japan gave me a lesson of high quality agriculture standards. Clean agriculture, dedication, discipline, and love for agriculture. It may be impossible in our modern days to achieve these lines especially with the modern mango industry which is based in production and low prices. The growers are subsidized by the government, and this is the only reason they still survive.

 

I am indebted to all my friends in Japan for the opportunity to experience what has been done with our Floridian mangos. These small, manicured trees symbolize the high level of patience and creativity of the Japanese grower. It is a life time of care; an opportunity to grow mangos out of the mango zone in South Florida and into the unknown of the northern United States and beyond. We can use some of these experiences to apply to other models where quality is the goal. Costs, in both time and money are high, but the reward is a labor of love that only the mango can command.