Why was Chapter 9 called 20 Days?

In the time of famine, the maize crop was thriving but would still require twenty days before harvest. Could the people last twenty days.... the title refers to this fact.

Meanwhile, out in the maize fields, the stalks were now as high as my father’s chest. The first ears had begun to form, revealing traces of reddish silk on their heads. The deep green leaves had begun their fade to yellow, along with the stem. While men withered and died all around, our plants were looking strong and fat.

“Twenty days,” I said, looking at my father.

“I’d say you’re right.” We smiled and stroked the leaves like swaddled babes, enjoying the soft music they created together in the breeze. If Iwas correct, we had twenty days until the green maize was mature enough to eat, something we lovingly called dowe.