🍅 Tomato How hard it is to control: ★★☆☆☆ 2/5

Blossom end rot on tomato

Physiological disorder caused by calcium deficiency in developing fruits. Not an infectious disease.

Symptom photos

Blossom end rot — Fruits cut in half — dry, brown-black rot at the blossom end — Fruits cut in half — dry, brown-black rot at the blossom end Photo: Siltloam, licence Public domain

Blossom end rot — Ripe fruit — dry, leathery patch at the tip — Ripe fruit — dry, leathery patch at the tip Photo: A13ean, licence CC BY-SA 3.0

Symptoms

Dark, watery spot on fruit blossom end
Spot darkens and sinks
Hard, leathery consistency
Occurs mainly on first clusters

What it does to the crop

Partial yield loss
Deterioration of fruit quality
Fruits unfit for sale

What encourages it

Irregular watering
Excessive nitrogen fertilization
High temperature
Low air humidity
Substrate salinity

Prevention

Regular watering
Balanced fertilization
Calcium fertilization (foliar and soil)
Mulching

⚠️ Before you reach for a spray

This atlas is informational and still growing — different diseases can look almost identical. Confirm the diagnosis and read the product label before applying any plant protection product. If you are unsure, ask your local extension or advisory service.

Keep the disease atlas with you in the garden

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