Maxsea All Purpose Plant Food Maxsea 16-16-16 All Purpose Plant Food is designed for year ’round use on all plants, indoors and outdoors. A regular feeding program will promote vigorous, sturdy plants with distinct, dark, seaweed green foliage, quality blossoms and abundant fruit and vegetables. Comprised of primary plant foods nitrogen, phosphorus and potassium. A full spectrum of important secondary elements and micronutrients provide sulfur, boron, copper, iron, manganese, molybdenum and zinc. The seaweed granules in Maxsea contains over 60 recognized elements all found to be beneficial to plants.