米善Sai no Kizuna vs Koshihikari
What you learn by growing both in the same Kawagoe paddies.
Grown in the same paddies — what actually differs
At Komeyoshi we grow both Sai no Kizuna and Koshihikari in the same soil and water in Kawagoe. Koshihikari, born in 1956, is the variety that defines Japanese rice. Sai no Kizuna was bred by Saitama Prefecture to stay delicious through hot summers, registered in 2012, and is grown only within Saitama. Two varieties from different eras, bred for different goals — growing them side by side in the same paddies lets us compare them under identical conditions.
How they grow differently (water, fertilizer, lodging)
Koshihikari has weak stems that lodge (fall over) easily in typhoons and heavy rain, and it is vulnerable to rice blast disease — a difficult variety to grow, in exchange for its taste. Sai no Kizuna was selected from plants that kept their grain quality through the record heat of 2010. It actively draws up water through its roots to cool its leaves and ears, making it exceptionally heat-tolerant, with built-in resistance to rice blast, stripe disease and leafhoppers. As summers on the Kanto plain grow hotter every year, this difference translates directly into a stable harvest.
How they cook and taste
Sai no Kizuna is lower in amylose, giving it a springy, mochi-like chew and a smooth texture, with a clean finish that balances sweetness and umami. Koshihikari is known for its strong stickiness and pronounced umami and sweetness — rice with real presence in the bowl. In the Japan Grain Inspection Association's taste ranking, Saitama-grown Sai no Kizuna earned the top 'Toku-A' grade for the 2024 crop (its 6th time, 5 years running). This is an evaluation of the variety and region — we do not measure or publish taste scores for our own rice.
Which rice for which dish
Sai no Kizuna's clean finish means it never fights with strongly seasoned dishes — grilled meat, fried food — it holds them up. An easy rice for everyday meals and bento boxes. Koshihikari, with its strong stickiness and sweetness, suits meals where the rice itself is the star: eaten fresh from the pot, in onigiri, or alongside traditional Japanese dishes. Cook either one following the 'How to cook' steps on each product page and the difference between the two comes through most clearly.
If you can't decide (the grower's answer)
If you can't decide, start with Sai no Kizuna. It is grown only in Saitama, pairs easily with rich everyday dishes, and is just right for the daily bowl. If you love the classic strong stickiness and sweetness, choose Koshihikari. New sign-ups for the Koshihikari-only subscription are currently paused, so try the 'Two Tastes' course, which alternates both varieties, or the 2kg-each tasting set. Tasting both, grown in the very same paddies, may be the best answer of all.