This year I am going to try planting Borage with my tomatoes, cucumber and squash; I have read it will deter the tomato horn worm! Of course basil and marigolds will also be planted nearby.
Here's a few other basic companions to help you get started with your gardenscape plans.
A beginner "goes good with" list:
Dill: cabbage, lettuce, onion, sweet corn, cucumer
Eggplant: Amaranth, beans, spinach, thyme, marigold
Geranium: Tomatoes, peppers, cabbage, beets
Kohlrabi: cucumber, onion chives, beets
Hot Peppers: cucumber, eggplant, tomato, basil, okra, oregano, parsley, rosemary, thyme
