Crop rotation

Question 1

Crop rotation - example

Answer 1

Plot 1 - 4 year cycle 
Legumes
Brassicas
Potatoes and others
Alliums and roots

Question 2

Limitations of crop rotation

6

Answer 2

Only effective against soil borne disease
Not effective against non-specific P&D
Space restrictions and commitments
Restrictions of choice
P&D are mobile over smaller areas (domestic situation)
Some P&D can survive many years (eg P C eelworm)

Question 3

Benefits of crop rotation

4

Answer 3

Help avoid build up of P&D in soil
Effective use of nutrients in soil (nutrient requirements of crops vary and rotation helps prevent depletion of particular nutrients = soil sickness)
Nitrogen-fixing legumes can be used by following crop of brassicas
Potatoes can help supress weeds for subsequent alliums