The smell of tomato leaves in the sun reminds me of happy days growing up in Tennessee. My sisters and I worked in the garden on weekends, pulling weeds and gathering fresh vegetables. We shared good times and hard work, but many years later, my favorite memory is of sampling tomatoes as we went.

Several years ago, a new catalog arrived in the mail. Heirloom tomatoes, which are passed from one generation to the next, adorned the pages: "Lillian's Yellow," "Cherokee Purple," "Black Krim," "German Red Strawberry." Each with its own unique color and taste.

Usually grown in the upper Midwest and along the East Coast, where they thrive, these heirlooms would be a challenge ...