(a) Except as otherwise provided in this part, the Secretary shall limit the shipment of Walla Walla Sweet Onions by any one or more of the methods hereinafter set forth whenever the Secretary finds from the recommendations and information submitted by the committee, or from other available information, that such regulation would tend to effectuate the declared policy of the Act. Such limitation may:

(1) Regulate in any or all portions of the production area, the handling of particular grades, sizes, qualities, or maturities of any or all varieties of Walla Walla Sweet Onions, or combinations thereof, during any period or periods;

(2) Regulate the handling of particular grades, sizes, qualities, or maturities of Walla Walla Sweet Onions differently, for different varieties or packs, or for any combination of the foregoing, during any period or periods;

(3) Provide a method, through rules and regulations issued pursuant to this part, for fixing the size, capacity, weight, dimensions, markings or pack of the container or containers, which may be used in the packaging or handling of Walla Walla Sweet Onions, including appropriate logo or other container markings to identify the contents thereof;

(4) Regulate the handling of Walla Walla Sweet Onions by establishing, in terms of grades, sizes, or both, minimum standards of quality and maturity.

(b) The Secretary may amend any regulation issued under this part whenever the Secretary finds that such amendment would tend to effectuate the declared policy of the Act. The Secretary may also terminate or suspend any regulation or amendment thereof whenever the Secretary finds that such regulation or amendment obstructs or no longer tends to effectuate the declared policy of the Act.