So, by far, the most important plant food is water, not just to keep a plant upright or to move nutrients into and through a plant, but also for the very basic building blocks of plant growth. Water gives us hydrogen and oxygen. We generally don t have to worry about the carbon dioxide, but we do have to worry about the water. Make sure your plants get lots of it. These are minerals that are generally of most concern to the gardener.
Sulfur is an essential component of proteins and fats.
Calcium plays several roles, in nitrogen uptake, protein synthesis, enzyme activation and cell reproduction. Magnesium is called a macronutrient by some, a micronutrient by others. Magnesium is an integral part of chlorophyll and activates plant growth enzymes. Many rosarians apply magnesium the form of epsom salts to stimulate basal breaks from the bud union, although there has been some discussion as to whether it really does so. Magnesium can come from dolomite lime or epsom salts.