Calcium moves with water in the plant. When the bed swings from bone-dry to soaked, fruit tissue can fail at the blossom end even if the soil test shows enough calcium. Foliar calcium sprays are a weak fix if watering stays erratic.
What to do first
- Mulch. Keep the top inches from baking and crusting.
- Water so the root zone stays evenly moist — finger test two inches down. See how often to water.
- Pick and discard the damaged fruit. The plant can set clean fruit later if conditions stabilize.
- Avoid heavy nitrogen that pushes leaves at the expense of balanced growth.
When to think about soil calcium
If rot continues after watering is steady, get a soil test. Adding lime or gypsum without a test can push pH or nutrient balance the wrong way. Raised beds filled with a compost-heavy mix are not automatically “low calcium,” but very peaty mixes sometimes need mineral balance over time.
Frequently asked questions
Is blossom-end rot contagious?
No. It is a physiological disorder. Fix the bed’s moisture and nutrition story; you do not need to sterilize tools for this one.
Will crushed eggshells fix it this season?
Shells break down too slowly to rescue fruit that is already forming. Focus on water and a soil test for next season.