Blossom end rot
Blossom end rot is caused by a lack of calcium in the growing fruit, and when this deficiency is solved, the afflicted plant can continue to thrive and produce perfect fruit later in the season. This condition is most seen in tomatoes, but also found in capsicum, chilli, squash, eggplant, cucumbers, and other fruiting plants.
What are the symptoms of blossom end rot?
Symptoms of beige or yellow discolouration start in the early stages of fruit formation. As the rot progresses, it expands and grows darker and tougher, where fruit appears shrunken and withered under the skin. Eventually, it can cover the entire bottom half of the fruit, often accompanied by browned and curled leaf tips around the affected fruit. As this condition isn’t caused by infection, fungus or pest it wont spread around your garden to endanger other plants.
The missing calcium isn’t necessarily a result of poor soil conditions. Most likely, the problem is that the plant can’t make full use of whatever calcium is available due to overwatering or heavy rain diluting the available calcium, underwatering or inconsistent watering putting the plant under stress or high acid or alkaline soil levels locking up nutrients making them unavailable to the plant roots.
The most common reason is that high levels of soil nitrogen are causing calcium deficiencies, with excess leafy growth diverting nutrients away from the fruit, causing abnormal development and secondly, nitrogen locking up the soil’s calcium in a salt form which isn’t readily available to the plant.
Treatment is to apply a foliar feed of diluted calcium fertiliser directly onto the plant’s leaves, pick off rotting fruits so the plant can concentrate energies into new growth, rule out or resolve soil deficiencies and a careful use of nitrogen-rich fertilisers. Improving soil quality by adding organic matter, compost and manures and following a consistent watering regime will provide longer-term results.
