Whole Foods Markets across the United States have slashed prices on organic kale to promote World Vegetarian Day. From now until Tuesday, organic kale will be available for $1 per bunch. The market is promoting the health benefits of the popular green, stating that it is a good source of protein, dietary fiber, iron, and calcium. In an effort to make healthy foods more accessible, Whole Foods began to cut prices on many plant-based foods—including avocados, nut butters, and bananas—after it was acquired in June by Amazon for $13.7 billion. Select Whole Foods locations in Los Angeles and New York are currently adding tomato-based vegan tuna to its sushi cases and a fully vegan burger bar—Oregon-based Next Level Burger—debuted last month at a Seattle location of the supermarket giant.