Some of the elements in seaweed are essential for plant growth. Essential elements are required by plants to grow and reproduce, and if the plant lacks even one of them, it cannot survive. Kelp includes all of the essential elements plants need, including nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, and all of the essential trace elements. But seaweed extracts also include a vast array of “beneficial” trace elements. Beneficial elements are not essential for plant growth, so if a plant lacks one or more of them it will still survive. But many of the beneficial elements in seaweed have shown to have positive effects on plant growth and stress resistance, or are essential to the people or animals that consume them!