Sake production starts in October, in September in an earliest case, and it continues until next Spring.
Summer is not a good season for sake production, mainly because of high temperatures.
Also, most of sake craftsmen in Niigata are engaged in rice farming. They are busy growing rice in late Spring until harvest in Autumn.

When snow disappears on the ground in April, rice growers plow rice fields, fill it with water and prepare for planting.
At the same time, they sow seed rice in greenhouse to grow seedling.
They plant seedling into rice fields in May.
They used to plant it by hand. Now it is replaced by a rice planting machine like this.

Rice planting in early - mid May

Rice is growing 30days after planting. It’s a lovely sight to see so much green after a long, snowy Niigata winter.

Rice in June - 30 days after planting

In mid August, the head are getting heavier.

Rice in mid August

The heads becomes brown late August. Harvest is just around the corner.

Rice late August

In September, they harvest rice. This kind of small size harvesting machine is typically used in Japan.

Harvest in September

After harvesting, they remove hull, dry brown rice and pack it in bags.

Unlike grapes used for wine, the quality of sake is much less affected by the average quality of sake rice on a yearly basis.
If a sake house has secured a skillful master brewer, he and his team can compensate for the change in rice quality.
And unlike wine, sake produced during a “bonanza” harvest year is not singled out due to the specific quality of the rice that season.