You should not grow a vegetable in the same spot year after year.If you do these two basic problems are likely to arise.

1. Soil living pests and diseases which thrive on the crop will steadily increase and may reach epidemic proportions.
2. Continuous cropping with the same vegetable may lead to the levels of soil nutrients becoming unbalanced.

Crop rotation is the answer using a standard 3 year plan.

• A=Root Crops EG: beetroot, carrot, chicory, jerusalem, artichoke, parsnip, potato, salsify, scorzonera
• B=Brassicas EG: broccoli, brussels sprout, cabbage, cauliflower, kale, raddish, swede, turnip
• C= Others EG: aubergine, bean, capsicum, celeriac, celery, cucumber, endive, leaf beet, leek, lettuce, marrow, onion, pea, spinach, sweet corn, tomato

A strip of land at the end of the plot is sometimes used for permanent crops asparagus, rhubarb, ect and is left out of the plan.Not everyone is able or willing to practise crop rotation, and unforttunately all idea of a rotation is abandoned.

It would be much better to follow a very simple routine - roots this year, an above ground vegetable next year and then back to root crop.With a proviso that if a vegetable does baddly one year then you should never follow it next year with one from the same group.

Preparation of soil

• Brassicas add some well rotted manure or compost at digging time if the soil is known to be short of humus.Lime the soil unless you are sure it is already alkaline. Rake in a general purpose fertilizer about 2 weeks before sowing or planting.
• Others add a liberal amount of well rotted manure or compost at digging time. Lime only if soil is known to be acid. Rake in a general purpose fertilizer about 2 weeks before sowing or planting.
• Roots do not add manure, do not lime, rake in a general purpose fertilizer about 2 weeks before sowing or planting.

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