what is it about?
The stanzas describe a progression through the season, from the late maturation of the crops to the harvest and to the last days of autumn when winter is nearing.
To Autumn
The poem has three eleven-line stanzas which describe a progression through the season, from the late maturation of the crops to the harvest and to the last days of autumn when winter is nearing. 
who wrote season of mist and mellow fruitfulness Keats what type of literary composition is "to autumn"? "To Autumn" has been regarded by critics as one of the most perfect short poems in the English language.
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To Autumn [SEP] Introduction
A little over a year after the publication of "To Autumn", Keats died in Rome. The poem has three eleven-line stanzas which describe a progression through the season, from the late maturation of the crops to the harvest and to the last days of autumn when winter is nearing. The imagery is richly achieved through the personification of Autumn, and the description of its bounty, its sights and sounds. It has parallels in the work of English landscape artists, with Keats himself describing the fields of stubble that he saw on his walk as conveying the warmth of "some pictures".