Yatsushiro City, in Kumamoto Prefecture, is Japan's #1 soft rush straw producing region. To this day, rich rural landscapes extend over the Yatsushiro plain, land reclaimed from the sea during the Edo period and nourished to this day by the Kuma River. All TATAMO! products use tatami covers made from soft rush straw produced by Sei Sonoda, a Kumamoto Prefecture certified eco-farmer.

The soft rush straw cultivated by Sonoda is actually a special variety.The most common variety of soft rush straw in the market today is called "Hinomidori", a fairly thin variety of soft rush straw. Beautiful and intricately woven tatami covers are made from Hinomidori straw, but it is this thinness which also makes it relatively fragile. Thats why Sonoda grows a thick, strong variety of soft rush called "Yuunagi". Tatami covers made with Yuunagi straw are thick and strong, with a solid feel.

A size comparison could be made by likening Hinomidori straw to thin rice flour noodles, and Yuunagi straw to thicker buckwheat noodles. You can feel it's Yuunagi straw when you step firmly on a tatami mat and it pushes back with elasticity.

"The reason I chose to grow Yuunagi straw is because I want our customers to experience its unique strength and vitality. I think people will be reinvigorated by living their daily lives in rooms laid out with tatami that is full of that vitality. This year I have also started growing a new type of straw called “Hinoharuka”, a variety which stays strong in snow and rain, and I am really looking forward to seeing a finished product using it."

Cultivation of soft rush straw typically starts with the planting of seedlings in mid-November and harvesting in late June in the following year. While herbicides and pesticides are sprayed during that period, Sonoda has decided to spray less than the standards set by the national and prefecture governments to reduce pesticides used in cultivation. Herbicide sprayings in Sonoda's fields finish by early May. He believes that spraying less and allowing a 2 to 3 month span before the harvest eliminates harmful effects of herbicides on the human body. Pesticide sprayings end 1 month prior to harvest. Producing good rush straw comes from scientifically grounded daily measurements and making a plan to ensure results.

"On one hot day a while back, I wasn't wearing a mask when spraying pesticides. I spent the day in a haze and there was even one hour where I couldn't remember what I did. I also felt nauseous all day. I guess it was my own fault for not wearing a mask," Sonoda said. From his firsthand experience, Sonoda began to think about the risks of pesticides and herbicides to humans.

The risks of agricultural chemicals affect not only consumers who lead their daily lives on tatami mats, but is also a serious problem for tatami producers. To minimize these effects, Sonoda started to visit the local farmers' cooperative to study the relationship between seasonal temperatures and the growth cycle of insect pests, and the varieties of chemicals that target different stages of insect life cycles. After thorough study and testing, Sonoda was able to formulate proven methods that apply the appropriate chemical in minimal amounts under predetermined conditions.

Every year, Sonoda tests his straw for agricultural chemicals. A strict regimen of over 100 tests are performed, but even a trace herbicide or insecticide has yet to be found. In other words, the straw has been proven safe enough for a baby to lick.

Sonoda's straw not only rates highly for safety, but also achieves superior ratings in tests for durability. A cut section of a tatami cover is rubbed with sandpaper and the change in the cover's thickness is measured. Regular tatami covers show average wear of approximately 0.35 millimeters. Tatami covers made by Sonoda hold a record at the Kitade Association for the Promotion of Tatami (of which Sonoda is a member), showing wear of only 0.02 millimetres. "I do sometimes like to brag about our tatami covers being the strongest in all of Japan," quips Sonoda.

Because soft rush straw is 100% natural, after cutting farmers generally recycle any waste straw as fertilizer by burying it directly into their fields or by incineration.

The process of making tatami covers starts with dyeing the harvested straw with mud. The straw is then dried and woven into covers using a special tatami weaving machine. A large number of the 80% of tatami covers in Japan that were made in China contain herbicides, pesticides and are dyed using artificial coloring agents.

Sonoda uses timeless traditional methods and dyes with only natural mud. And because the thread used in weaving the tatami covers (for products that use this thread) is flax and pure cotton, the tatami covers can return to nature over time.

Well maintained tatami mats can generally last for 10 to 20 years. TATAMO! aims for a lifestyle with soft rush that can coexist with new designer products.