Both water and minerals are essential for plants. Plants absorb water and minerals from soil. There are 113 or so different elements in this planet, of which fourteen or fifteen are absolutely required for the life processes without which plants exhibit diseased symptoms and ultimately die. The process of absorption of water and minerals is described very briefly:
Cell division region at the top of the root is known as mineral absorbing area, some salts also absorb by root hair. Plant cannot take solid salts. The salts (minerals) dissolve in soil-water and converted to Cation (+) and Anion (-), root absorb them as ions. Na+ is a Cation cr is an Anion. Kt, Ca-I+ are Cations; NO3, P0; SO are Anions.
Most plants secure the water and minerals they need from their roots. The path taken is: soil -> roots -> stems -> leaves. The minerals (e.g. K+, Cat +) travel dissolved in the water (often accompanied by various organic molecules supplied by root cells).