As the weather warms, Marie Viljoen laments the abundance of watercress in the city. Though she grew up harvesting the peppery plant where it grew wild near her home in Cape Town, South Africa, she knows that polluted city water makes urban watercress too risky to eat. But with spring upon us, she shares tips for how to eat the stuff (purchased from your local greengrocer, not picked from Prospect Park!) here in our current issue.