What is Crop rotation
Before planting out each year in the veg plot, the first decision is what to grow, what is going to be planted in which bit of the plot, and how to rotate Crops year on year.
Crop rotation is important because as it quickly becomes obvious, when growing vegetables, disease and pests are the enemy. Crop rotation seeks to prevent build up in the soil of diseases and pests particular to that type of vegetable, by not growing the same vegetable in the same soil each year. In addition, some vegetables, the pea and bean family, fix nitrogen in the soil and so the next crop should be one that thrives with the extra nitrogen. There are good reasons to organise crop rotation which does it's bit to help keep disease at bay.
Traditionally crops fall into 4 groups
Legumes → Alliums → Roots → Brassicas
All the Peas and Beans including Onions, Spring onions Potatoes Tomatoes Beetroot Kale Cabbage Broccoli
Runner, Broad French Beans and Shallots Leeks and Garlic Aubergines, Celery, Celeriac Cauliflower Brussels sprouts
Peas. Sweet Potatoes and Peppers Pak Choi Kohl Rabi
Parsnip and Carrots Swedes Turnips and Radish
Each year if you are planting a veg from one of groups, it needs to be planted in a different bed from the previous year. The best way is to draw a plan/take photos and compare it with last year to make sure the crops are rotated. Salad vegetables should also be planted in a different bed each year. A plan helps to decide how many of each veg to grow and track the crop rotation from year to year. By moving the crops around you will reduce the incidence of disease which can be a problem when growing vegetables particularly with wet summers.
When planning the veg plot don't discount last years seeds. Seed is increasingly expensive and for some vegetables such as courgettes, a couple of plants is often enough, and often last year's seeds will be viable and it is always worth trying to germinate from the previous years seed. It varies from seed to seed, and ideally if you are storing seed over the winter put in a cool place in airtight tin, the fridge is ideal if not a cool garage. The one seed you do need to buy fresh each year is Carrot seed.