Heat olive oil in a large skillet over low heat. Cook and stir bacon until browned and crisp, 3 to 5 minutes. Add garlic; cook and stir until golden brown, 1 to 2 minutes.
Stir beet stems and kale into the skillet. Cover skillet and cook until kale wilts, about 3 minutes. Add beet greens. Cover and cook until bright green and wilted, 1 to 2 minutes. Season with salt and pepper.
