On many occasions we find ourselves the unpleasant surprise of discovering white spots on the leaves or stems of our plants, whether they are indoors or in the orchard or garden. Unfortunately, there are a large number of possible causes that can cause these types of symptoms, and it is worth mentioning each of them and their possible treatments separately.
If you want to learn more about the pests and diseases that cause light spots on leaves, join us in this article in which we talk about the causes and treatments of white spots on plant leaves .
White spots on plant leaves – causes
As a summary, we leave this list of the main plant diseases and pests that can cause white spots on the leaves :
- Powdery mildew and other types of fungi on plants.
- Red spider.
Powdery mildew: main cause of white spots on plant leaves
Powdery mildew, also called bad white of plants, is undoubtedly the main cause of white spots in a large number of plant species around the world. It is a disease caused by a fungus, which affects a huge number of crops, among which the damage suffered in the vine and vegetables stands out, especially in tomatoes, beans, potatoes, chard and a good part of cucurbits, such as cantaloupe, watermelon, squash, cucumber, and zucchini. In addition to these, ornamental-type plants are not safe as, for example, rose bushes.
The powdery mildew fungus appears in the form of small white spots on the leaves , usually located on the upper part of the leaves, but which can spread over its entire surface and even on the fruits of the plant. It is easy to detect, and as it develops, the white spots eventually form a whitish, ash-like dust.
If it is not fought in time, the presence of the spots does not allow the plant to carry out photosynthesis adequately, and it can end up drying the leaves and rotting the fruits. The fungus appears when temperatures are warm and humidity is high, so its arrival is very common in spring in temperate zones, or throughout the year in tropical climates. If your garden meets these two conditions, it is very likely that powdery mildew will eventually appear. Luckily, fighting it is not difficult. As in all cases of fungi, the first thing to do is properly remove and remove the leaves and affected areas. Later, we will be able to resort to home and ecological remedies, not being necessary to resort to synthetic chemical fungicides. Horsetail or garlic infusions are especially useful, or the homemade fungicide made with milk.
Botrytis, another fungus that causes white spots on leaves
Botrytis is another disease, also quite common, caused by a fungus. Like powdery mildew, botrytis appears in humid and warm climates and appears in the form of gray or whitish areas of rot on the fruits and shoots.
Fighting this fungus in plants is somewhat more difficult than eliminating powdery mildew or mildew and although ecological fungicides can work preventively, their elimination is more complicated. It is vital to maintain a very good drainage in the soil or soil of the plants, in addition to favoring the circulation of air currents, separating the plants and pruning them so that they are not so closed.
Treatment of white spots on leaves – fungicide with milk
To prepare a natural fungicide with milk , you just need to follow these steps:
- Mix 4 parts of rain water (or water that has remained for 48 hours if it is from the tap) with one part of milk, if possible it is skimmed to remove the fatter part.
- Add 20 grams of baking soda for each liter of fungicide to be made.
- Mix it well until you see it homogeneous.
- Spray the mixture after each rain and every 15 days on all plants, both affected and healthy, preventively. This fungicide also represents a great supply of very healthy nutrients for plants.
Red spider on plants
Despite its name, this pest is actually a very small mite that can be red to white depending on the species. When the pest appears, some plant leaves can show a large number of tiny white spots on the leaves , caused by the mite sipping the juices of the plant to feed itself. When there are a large number of them, they can be seen with the naked eye and form cobwebs, with which they travel to nearby plants. They hide on the underside of the leaves, and can be fought with Neem oil or potassium soap, in addition to increasing the humidity in the leaves, because the pest does not support high humidity.