how can I naturally cure the rust of my succulents
the rust of succulents is caused by a fungus, commonly called septoria; for this reason it would be better to call the disease septoria of succulents; these fungi insinuate themselves in superficial areas of the cactus, where they find wounds or fractures of the cuticle that covers the stems and leaves; once inside, they tend to develop both superficially and penetrating deeper, also causing very serious damage. If the fungus has recently entered the plant, it can be removed by removing the yellowed part with a scalpel (or with a sharp and clean knife). It is clear that this method leaves many scars on the plant, which should be repaired with mastic for pruning. In general, a systemic fungicide is used against septoria, that is, it has the characteristic of penetrating inside the plants, through the cuticle that covers them; these fungicides must be mixed in water and then vaporized on the areas affected by the disease: it will not be possible to make all the spots disappear, but at least you will stop their growth, and you will kill the fungi that caused them.
Unfortunately for this type of use you will have to buy a synthetic fungicide, such as propeconazole, or similar products; to prevent the development of other fungi, and the spread of those already present, you can treat your plants with products based on copper, which is not as toxic as synthetic fungicides. It would also be advisable to ensure your plants greater ventilation, and prevent them from getting wet, either due to bad weather or by watering them from below and not spraying them from above, as if they were taking a shower; in fact many fungal diseases develop due to poor ventilation and high humidity.
Watch the video