Rotation is rotation. No need to be an annual event, just remember the prime reason for doing it is to prevent buildup of plant specific disease. On allotments, crop rotation can be quite tricky to do in its purest form if maximum production is required.
I do not believe in leaving land fallow and prefer intensive cropping with plenty of added manure. Once my onions, shallots and garlic are all harvested, the space will be re-used for tomatos, peppers and any other odds and ends that will produce during the summer yet free the land for digging during the winter. The secret is to ensure that all plants in the section will be finished at roughly the same time to enable further usage.
