12 Top Tomato Tips (from Birds & Blooms): The rule of thumb is that you'll need two tomato plants for every tomato eater in your household. But if you plan on canning, four per person is more accurate.
Grow Onions from Discarded Onion Bottoms. Let cut root end dry out for a few days, put in starter pot. Once roots develop, remove outer wilted onion layers. Plant in garden. Larger onions can be cut into multiple sections as long as roots are on each.