The invention discloses a safety production method for
crop rotation planting of sweet potatoes and oilseed rapes in a heavy
metal polluted farmland instead of
crop rotation. The method is used for
crop rotation of summer crops sweet potatoes and
overwintering crops oilseed rapes on Cd and Pb moderately and heavily polluted soil, and specifically comprises the following steps: (1) the sweet potatoplanting period is from June to October, and the oilseed rape planting period is from October to May of the next year; (2) carrying out farmland weeding,
impurity removal, ditching and leveling workaccording to the planting requirements and the field area; (3) applying a
soil conditioner before sweet potato planting; (4)
transplanting the sweet potatoes with the varieties of 98 Hunan potatoes, 19 commercial potatoes, 24 Suzhou potatoes and 98 Yu potatoes; (5) after the sweet potatoes are ripe and harvested, removing overground stems and leaves from the field, and performing centralized
recovery treatment; (6)
sowing and planting oilseed rape of which the variety is
saliva oil 823, oil
millstone 2013, Hunan miscellaneous oil 631 and oil-rich
millstone 108; and (7) after the oilseed rape is mature and harvested, removing all straws on the ground from the field, and carrying out centralized
recovery treatment. Low-accumulation-character sweet potatoes and oilseed rapes are selected forcrop rotation, the planting method is simple, and the total amount of heavy
metal in farmland soil can be reduced year by year.