Just because it’s cold outside, doesn’t mean your edible gardening needs to stop. Put leftover seeds to good use by growing your own microgreens indoors. These nutrient-packed greens add fresh flavor to many of your favorite salads and sandwiches. Microgreens add fresh flavor and nutrients to salads, sandwiches, smoothies and stir-fries. These plants are harvested when they’re young, usually about two weeks after planting.   Plus, microgreens contain about five times more vitamins than if grown to mature vegetables, according to USDA researchers.