Blossom end rot is a common problem that occurs on tomatoes, but also on peppers and eggplants.
Other names: Black rot, Dry rot
Other names: Ξηρή Σήψη, Ξηρή Κορυφή, Τάπωμα
Symptoms
Blossom end rot is a common problem that occurs on tomatoes, but also on peppers and eggplants.
The appearance of the problem starts with a dark spot 1 to 2 cm in diameter at the bottom of the fruit. The spot is dark in color. Tomato, eggplant, pepper becomes dented at the point where the spot appears.
The spot gradually increases in size and spreads to cover the entire lower part of the tomatoes, eggplants, peppers.
Although blossom end rot causes only a local problem, the problem gets worse as organisms take advantage of the infection and enter the fruit. The result is rotting of the fruit.
Various varieties of tomatoes have different resistance to the problem.
For example, small tomato varieties such as Santorini tomatoes and cherry tomatoes are very resistant and rarely have a problem with blossom end rot.
In contrast, varieties that produce regular or large tomatoes are very susceptible to the problem.
Causes
The most likely causes of the problem are:
- Calcium deficiency – soil with little usable calcium
- Lack of calcium absorption
- Inconsistent watering
- Excessive use of fertilizers containing nitrogen, magnesium and potassium, which work in competition with calcium
- Low soil pH
- Soil that is easily washed away or retains too much water
- Prolonged water deficiency
- Intense heat during the growth phase of the fruit
- Use of unsuitable potting soil combined with irregular watering
Treatment
- Add calcium to the soil before planting. Calcium can be added in the form of marble dust to be mixed with the soil. The addition of calcium also increases the pH of the soil
- Limiting the use of fertilizers containing potassium, magnesium, nitrogen and ammonia
- Constant irrigation (watering) schedule
- Periodic trans-wave spraying of plants with phosphate fertilizers or calcium nitrate or calcium chloride during the afternoon hours
Source
Tomato diseases and disorders (PDF) by Mark L. Gleason and Brooke A. Edmunds, Department of Plant Pathology
Blossom-End Rot in Tomatoes: Causes and Prevention
Blossom end rot – RHS
Tags: PLANT DISEASE • TOMATO • TOMATOES