(a) Nothing in this chapter shall be construed to prevent a grower from selling potatoes at his or her premises or storage, or delivering potatoes to a central packing house, processing plant, storage, or to a retailer or consumer in quantity of five bushels or less in any calendar day without such marking, except that any potatoes displayed or offered for sale at the roadside must be marked with the proper grade.(b) Properly tagged certified seed potatoes as defined by sections 611-618 of this title are exempted from the provisions of this chapter.