House plants in living rooms require fertiliser to give them a sufficient supply of nutrients, as after some time the plants have used up the most important nutrients from the pot soil. You can use various fertilisers for this, for example organic fertilisers, fertiliser granulate or liquid fertiliser.
The quantity and frequency of fertilising depends on the plant: fast-growing plants generally require more nutrients than slow-growing ones. With regular fertilising, the plant receives important minerals such as phosphorous, nitrogen, potassium and magnesium, which they absorb via the roots. The additional nutrients in the soil help the plant to become more resistant and produce lush blooms. A higher phosphorous content is especially important for plants before or during the blooming stage. You do not always have to use a special fertiliser for this. Often there are simple household remedies that can be used, such as eggshell stock, brewed tea leaves or coffee grounds. Coffee grounds, for example, contain potassium, nitrogen and phosphorous. They are also environmentally friendly and virtually free. Note that the coffee grounds should be dry when mixed with the plant soil, as wet coffee grounds can go mouldy more easily:
However, do not over-fertilise, as otherwise you make the soil too salty and may even damage the plants. With too much fertiliser, the plant grows faster at first with larger leaves. Later, however, this may lead to a weakening of the plant and production of too much sugar, which attracts pests or vermin. Generally, therefore: fertilise less rather than more and never in too high concentrations, as the plants may then perhaps grow more slowly – but are not damaged by excessive fertilising.