A little about plant feeding
A plant’s need to be fed depends very much on lighting conditions. In many cases, the level of light in a home will not be sufficient for a plant to grow very much at all – just for it to survive in the short or longer term. Therefore, in most cases, there will be little need to feed the plant either.
If you add more fertilizer than the plant is able to utilize, the concentration in the potting medium will become too high. Too high a concentration of fertilizer inhibits the plant’s ability to absorb water and can kill the roots.
As a rule, only add fertilizer if the plant has sufficient light to enable growth. In other words, during the summertime and if the plant is positioned close to a window.
Plants need a great many nutrients (N, P, K, Mg, S, Ca, Fe, Mn, B, Zn, Cu, Mo). When you buy a plant, the potting medium will already contain a certain level of these minerals. Depending on the growth of the plant, sooner or later it will need more fertilizer.
The easiest way to add fertilizer is to buy liquid plant food and add it to the water. The vast majority of liquid plant foods in the shops will contain the necessary nutrients. Follow the instructions on the bottle. But it is better to err on the side of using too weak a solution than one with too high a concentration.