Blossom-End Rot and Calcium Nutrition of Pepper and Tomato
Had the ancient Roman Empire not developed concrete and cement, the domed buildings, arched bridges and aqueducts we see today would not still give testimony to the Romans’ ingenuity or to the durability of a simple mineral: limestone. Although calcium (Ca) is well known as the main ingredient in limestone, it has also been used for building strong plant cell walls since long before man discovered its uses for lasting architecture.
Calcium serves several functions in plants, including cation-anion balance, transport processes of cell membranes and assisting with extension of primary root systems. For vegetable producers, calcium’s most important function during the crop fruiting stage is its role in cell wall/cell membrane stability. If Ca is deficient in developing fruits, an irreversible condition known as blossom-end rot (BER) will develop. Blossom-end rot occurs when cell wall calcium “concrete” is deficient during early fruit development, and results in cell wall membrane collapse and the appearance of dark, sunken pits at the blossom end of fruit. Many farmers and gardeners may treat this condition as a fruit disease; however, nutrient and water management regimes are the culprit. The purpose of this publication is to introduce the problem of BER and provide a guide to effectively diagnose and treat this problem.
- Is the problem disease- or nutrient-related?
- Is calcium fertilization adequate?
- Is nitrogen and potassium fertilization excessive?
- Is irrigation adequate?