keep shells in open container in fridge. When full, crush shells into small bits and sprinkle around base of plants. Sharp eggshells will deter slugs, snails, and other bugs from nibbling on garden and add touch of calcium to soil.
Container garden-Note the wall of food gardening, the tomatoes are on the trellis. Use indeterminate tomatoes for the trellis because they are the ones that grow large. the trellis could probably even be used for peas or beans