Sale of non-farm products. Farm markets may sell the following non-farm products: landscaping and gardening items including but not limited to plant container, seed, bulbs, fertilizer, pest control items, bags of mulch and soils, gardening decorations and tools, and other similar gardening accessory items, and the limited sale of pre-packaged snack foods and beverages provided that the sale of all non-farm product items is clearly accessory to the principle farm market use and that the area devoted to the sale of such non-farm products does not occupy more that 20% of the total square footage used to display all the products offered for retail sale on the property and that such non-farm products do not comprise more than 20% of the total gross dollars of all products sold. The Zoning Administrator or Planning Commission as applicable may allow other non-farm products to be sold provided they are similar to those items listed above.