This is very important to keep crops healthy. Traditionally, crops are divided into four types:
French beans, peas, runner beans, broad beans
radish, carrot, potato, onion, garlic, beetroot, swede, sweet potato, shallots
spinach, chard, kale, cabbage, cauliflower, broccoli, spinach
tomato, sweetcorn, cucumber, squash, pumpkin, courgette, aubergine
Just make sure you move them around every year with your planting plan, so the same type of crop isn’t in the same place year after year.