Rotation is a system whereby groups of vegetables are grown on different sections of a plot of ground each year. In so doing, this maintains the balance of soil nutrients for successive crops and avoids the build-up of pests and diseases, as well as assisting in weed control and preventing soil deterioration.
For crop rotation to be effective, a large area of ground is required, particularly in an effort to control soil-borne pests and diseases, including white rot, which attacks the onion family; clubroot, which damages members of the cabbage family; and the potato cyst eelworm, which remains dormant in the soil for many years and can survive on any weeds which are relatives.
Before planting, a list should be made of the vegetables to be grown, grouping them together according to their botanical relationship. Allocate each group to a plot and then compile a monthly cropping timetable for each space. Then allocate each rotation group to a plot of land marked A, B, C, and D, for example, and draw up a month-by-month timetable for each space. This may sound too time-consuming, but can be done during the lazy winter months and will save so much more time later than fighting disease and pests because it was not done.
The following timetable fully utilizes the land and provides continuity of cropping. As space becomes available, plant crops due to follow immediately. For example, brussel sprouts and leeks cleared early in the spring can be followed by peas, salad onions, and lettuce. Crops may come from different groups, which means that the rotation from one plot to another is a gradual process rather than a wholesale change-over on a pre-set date.
Example rotational groups:
Legumes : broad bean, French bean, pea, and runner bean.
Onion family: bulb onion, garlic, leek, salad onion, shallots.
Carrot and tomato families: carrot, celery, pepper, parsnip, potato, tomato.
Brassicas: cabbage, cauliflower, radish, swede, turnip.
Year 1
Plot A: Legumes
Plot B: Onion
Plot C: Carrot and tomato
Plot D: Brassicas
Year 2
Plot A: Onion
Plot B: Carrot and tomato
Plot C: Brassicas
Plot D: Legumes
Year 3
Plot A: Carrot and tomato
Plot B: Brassicas
Plot C: Legumes
Plot D: Onion
Year 4
Plot A: Brassicas
Plot B: Legumes
Plot C: Onion
Plot D: Carrot and tomato
