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A rotation should include at least 4 different crops. In mountain regions and in areas with special conditions, this might not apply.

The crop rotation consists out of a number of crops grown in a specific order. The added value of this team of players (crops) increases the more attention is given to a careful design of the rotation: finding an optimum team and line-up. It is therefore recommended to design an optimal crop rotation following the next two steps:

1. Select and characterise potential crops with respect to:

a) their production-ecology characteristics, marketability and profitability (soil, climate, infrastructure, market, auctions, industry, labour-, capital- and machinery demand etc.),
b) Their plant families (legumes, crucifers etc)
c) Their phytopathological profile: range of pests and diseases than can affect the crop (indicate if they are polyphagous or specific)
d) Their management demands profile, like sowing time.
e) their potential role concerning;

• prevention and control of pests, diseases, weeds (resistance, tolerance and required or possible control measures),
• physical soil fertility (especially effect on soil structure on compaction-susceptible soils),
• chemical soil fertility (N need, -offtake, – transfer, organic matter supply),
• cropping period and soil cover (soil protection for erosion-susceptible soils).

2. Design of the rotation with a maximum of positive and a minimum of negative interactions between the crops. Take into account:

a) prevention and control of pests and diseases by the crop rotation composition: crops, frequencies and sequence,
b) soil fertility in the broadest sense and in particular organic matter- and N dynamics,
c) diversification crop – pest, disease weeds interactions,
d) feasibility crop sequence in terms of harvest time, crop residues and volunteers from preceding crops,
e) agronomic optimal use land, labour and equipment.

The obvious tension between agronomic potentials and economic performance determines the final set-up. However, economic performance should be evaluated at rotation/farm level on the midterm and not on crop level on the short term.