If you want to make your plants more cold-resistant and therefore fit for winter, you should start giving them fertilizer with a high potassium content in autumn.
Potassium and its effects
The reason is very simple: potassium accumulates in the vacuoles and increases the salinity of the cell juices. The increased salt concentration makes the plant less susceptible to frost. The freezing point is lowered. But that's not all. At the same time, the juice pressure in the roots is increased. As a result, both gas exchange and water transport are improved. The function of the so-called gap opening of the leaves is also improved. As a result, more water evaporates and more carbon dioxide can penetrate the plant tissue for photosynthesis.
Do not fertilize all plants
However, you should not fertilize all of your plants with a fertilizer that has a high potassium content. You should only provide the plants with such a potassium fertilizer, which are also prone to freezing. Plants that could get problems from a temperature of -5 degrees should be fertilized for safety reasons. The lawn will also gratefully accept a potassium fertilization. Older plants in particular do not naturally have as much potassium in them as young plants. Therefore, it is very important for older plants that you provide them with enough potassium in winter.