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Prevent Blossom-end Rot

Tomato blossom end rotBlossom-end rot is a fruit disorder that causes the blossom end of tomato, pepper and watermelon fruit to rot. The first symptom is a slight water-soaked area on or near the blossom end of the fruit. The affected area soon darkens and enlarges in a constantly widening circle and develops a tough, leathery feel. It is usually worse on the first fruit cluster but can be a problem throughout the season.

It occurs when there are extremes in soil moisture resulting in calcium deficiency in the fruit. When rain or irrigation follows a dry spell, the roots cannot take up calcium fast enough to keep up with rapid fruit development. Blossom-end rot also occurs if the delicate feeder roots are damaged during transplanting or by deep soil cultivation near the plants.

Prevention tips:

  • Water regularly or mulch to keep moisture levels consistent.
  • Maintain soil pH 6 – 6.5 and adequate calcium levels using dolomitic lime.
  • Avoid the temptation to apply too much fertilizer. This inhibits calcium uptake.

For more information, call Buncombe County Cooperative Extension at 255-5522.