The problem may occur for several reasons.
In rare cases, it is all about the varietal characteristics, but more often tomato leaves change color if they freeze or experience a lack of phosphorus.
The last two options should be examined in more detail.
Temperature drop
If seedlings are grown on a windowsill, then it is not surprising that they turn blue.
The fact is that the plant's purple color is given by anthocyanin pigments. As the temperature drops, the pigment becomes more abundant.
As a result, the stem and leaves turn blue.
Experts recommend hardening off seedlings. For example, opening windows for a while or taking the plants out onto the balcony.
Phosphorus deficiency
In this case, the back of the leaves changes color. As a result, the leaves then curl up and fall off. Therefore, it is necessary to urgently perform phosphorus fertilization. Any fertilizers that are sold in specialized stores will do.
But there are situations when the element is already in the soil, but it is blocked by another agent. For example, this can happen with increased or decreased soil acidity. In this case, "Phosphatovit" will help out perfectly.
