Root. In the computer world, root refers to the top-level directory of a file system. The word is derived from a tree root, since it represents the starting point of a hierarchical tree structure.
Use a fertilizer with high levels of phosphorus. Phosphorus helps to prevent aluminum from creeping into the system of the hydrangea. Choose a fertilizer close to the ratio of 25/10/10 (Phosphorus is the middle number).
Phosphates are also used to make certain glasses (e.g., for sodium lamps). Trisodium phosphate is used as a cleaner, water softener, and scale/corrosion inhibitor. Bone ash (calcium phosphate) is used to make chinaware and to make monocalcium phosphate for baking powder. Phosphorus is used to make steels and phosphor bronze and is added to other alloys. There are many uses for organic phosphorus compounds. Phosphorus is an essential element in plant and animal cytoplasm.