"Plants have best friends just like people do. Marigolds help tomatoes and roses grow better. Nasturtiums keep bugs away from squash and broccoli. Petunias protect beans from beetles and oregano chases them away from cucumbers. Geraniums keep Japanese beetles away from roses and corn. Chives make carrots sweeter, and basil makes tomatoes even tastier":
Tomatoes need calcium to achieve their full flavor potential, and calcium is often greatly lacking in our soils. 95% of a dry eggshell is calcium carbonate. When planting your tomato plants crush up (to powder) about 4 or 5 egg shells and put them in the bottom of the hole. Then plant your tomato on top. They provide calcium and prevent blossom end rot.