black spots on poblano peppers - Ask Extension
Can you tell me what might be causing these black spots on my poblano peppers? The spots start out small and get bigger and then some spots turn a tan...
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black spots on poblano peppers #716011
Asked August 21, 2020, 1:44 PM EDT
Can you tell me what might be causing these black spots on my poblano peppers? The spots start out small and get bigger and then some spots turn a tannish white color. It almost looks like a burn mark, but I'm not sure if this would be considered sun scald because it hasn't been scorching hot, and the plant gets only about 4-6 hours of sunlight. Just wondering if maybe this is some type of fungus and I need to get rid of the plant at the end of the season, or if I could put some kind of fungicide on it and overwinter it. It also doesn't happen on every pepper... seems like the first ones to grow are getting this. Any help you can provide would be great, thank you!
Macomb County Michigan
Expert Response
Thanks for the question. This is a case of blossom end rot, the same thing as found on tomatoes. It is a calcium deficiency usually due to uneven or excess watering at a critical stage in fruit growth. It is not unusual for first fruits show this. A soil test will help determine if you have a nutrient imbalance. Check out the following links:
- https://www.canr.msu.edu/uploads/resources/pdfs/blossom-end_rot2011.pdf
- https://apps.extension.umn.edu/garden/diagnose/plant/vegetable/pepper/fruitrotten.html
- https://extension.umn.edu/plant-diseases/tomato-disorders
Thank you for the response. Would adding calcium or garden lime to the soil help with this anyway, even though all of my plants are in containers and doing a soil test doesn't make sense since the soil will be discarded at the end of the season? I do make sure to water evenly daily, especially during hot spells, and this plant is in a container that drains well.
Most soils have adequate levels of calcium; however, calcium uptake can be limited by uneven watering or excess watering. With containers watering may be required more than once a day to insure consistently moist (not wet) soil. Nutrient imbalance can also inhibit calcium uptake. Adding calcium or lime may help but could change soil pH causing problems of uptake with other nutrients. If you are fertilizing be sure that the fertilizer has secondary nutrients and not excessive nitrogen. Adding supplemental calcium can be risky but it may help. Here is another article:
Great info... will definitely keep an eye on the containers and water twice a day if necessary. Thanks again!
