Blossom End Rot on Patio Tomatoes: Calcium Deficiency Fix

The Problem

Large brown/black spot on the blossom end = blossom end rot, caused by calcium deficiency in the fruit. Common in containers because calcium leaches out with frequent watering.

Solutions

• Pot up progressively: Each time you move to a larger container, add fresh potting mix (Miracle‑Gro) – replenishes calcium.
• Calcium supplement: Crush Tums (calcium carbonate) tablets into the soil monthly.
• Consistent moisture: Avoid wet/dry cycles – they impair calcium uptake.

Research

Search “calcium deficiency in tomatoes” for extensive university resources.

With steady moisture and periodic calcium replacement, blossom end rot is preventable.