Many people do not know the different crop families and what is related to what.
For a good crop rotation you should always plant different families each yeah instead of just planting potatoes in the same spot every year. This limits the amount of pest and disease your plants will have by rotating out things. It also helps with the minerals and nutrients in the soil by not depleting them.
Most people know that corn uses alot of nitrogen. And Beans provide nitrogen. So if you have a plot and you plant corn in it one year the next you should plant beans to replinish the nitrogen the corn used the previous year.
I hope this isnt too long but here is a list of different crop families.
Carrots Celery Celeriac Parsley Parlsey Root Parsnip
Artichoke Chicory Dandelion Endive
Arugula Boccoli Brussel Sprouts Cabbage Cress Kale Kohlrabi
Mizuna Mustard Radish Rutabaga Totsoi Watercress
Beet Orach Spinach Swiss Chard
Cucumber Melon Pumpkin Squash
Asparagus Garlic Leek Onions
Claytonia (Miners Lettuce) Puslane
Eggplant Tomato Pepper Potato
New Zealand Spinach