The plains growing season is short and precious — a narrow window, some months long, between the last killing frost of spring and the first of autumn, in which the entire crop must be planted, grown and brought to maturity. The whole calendar of the farm bends to this window, and the grower watches the frost dates as anxiously as any figure in the almanac.

The Window Between the Frosts

The shortness is a hard master. It rules out crops that need a long, warm season, favors the fast-maturing varieties the breeders provide, and punishes the grower who plants too early into a late frost or too late for an early one. An autumn frost arriving even a week ahead of schedule can catch a crop before it fills and dock its value or destroy it outright.

From the almanac's reckoning:

• The growing season runs between the last spring and first autumn frost.
• The short window favors fast-maturing crop varieties.
• Long northern summer days pour extra sunlight on the crop.

Yet the season, if short, is also gloriously bright, its long northern days pouring sunlight on the crop from before dawn until well into evening. The almanac keeps the frost dates faithfully, for on the plains the calendar is written in the coming and going of the frost.