Nairobi, Jan. 12 -- We are seated in a stall belonging to Doreen Wanja*, a woman in her 50s who has been a greengrocer for decades.

She operates in one of the public markets in Nairobi. It is minutes past midday, so she has a few customers to attend to.

"I woke up at 4.30am today because the truck bringing my products from West Pokot arrived in Nairobi earlier than I expected.

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"Depending on what is available, I usually source lemons, pumpkins, avocados and mangoes and resell," she says.

As she rearranges her mangoes, we are joined by one of her friends, Josephine Atieno*, who is also a greengrocer. She is also in her 50s and has been in the same market for ...