Why Do My Banana Peppers Have Dark Streaks?

If you’ve ever noticed dark streaks on your banana peppers, you might wonder what causes them. Luckily, there’s no need to worry – in most cases, those dark streaks are a sign that your peppers are ripening. Keep reading to learn more about why banana peppers develop dark streaks and how you might prevent them.

Ripening Banana Peppers

Why Do My Banana Peppers Have Dark Streaks?

The vast majority of the time, dark streaks on banana peppers are a positive thing – they signify that the peppers are ripening! As banana peppers mature, they’ll often develop darker streaks on their skin. This is entirely normal and doesn’t indicate anything wrong with the pepper. 

These streaks result from the accumulation of anthocyanins, which are pigments that give peppers their characteristic red, purple and blue colors. The stripes are purely cosmetic and don’t affect the flavor or quality of the pepper; in fact, anthocyanins possess pretty potent antioxidant properties. So go ahead and sprinkle them into your favorite recipe – your taste buds won’t be able to tell the difference!

Too Much Sun Exposure 

Sometimes, sun exposure is to blame for dark streaks appearing on banana peppers. Peppers exposed to too much sunlight can develop dark spots or stripes on their skin. This is because the UV rays from the sun can cause the pepper’s skin to break down, leading to an adverse chemical reaction on the fruit’s flesh. This process causes the pepper to develop a dark, streaked appearance. In some cases, a bitter flavor may accompany the streaks.

If you notice that your banana peppers have started to develop dark streaks after being in direct sunlight for extended periods, try moving them to a shadier spot. You can also use a fabric row cover to protect your plants from over-exposure. Just be sure to remove the covers during pollination so that bees can access the flowers and help with pollination.

Exposure to Cooler Temperatures

Why Do My Banana Peppers Have Dark Streaks?

Another reason you might find dark streaks on banana peppers is the temperature. Some peppers can develop dark lines as temperatures cool off in the fall. But, again, these are harmless and will not affect the taste of the pepper, however unsightly they may be. In addition, pepper plants don’t tolerate cold well, so cooler temperatures can stress the plant and make it more susceptible to disease.

If you notice dark streaks on your banana peppers as the temperature starts to drop, try moving the plants indoors or covering them with a fabric row cover. This will help protect the plants from the cold and allow them to continue ripening their peppers.


Most of the time, dark streaks are nothing to worry about – they simply indicate that the fruit is ripening. However, in some cases (such as exposure to sun or cold temperatures), the cause is environmental and can be remedied by taking steps to protect the peppers from the elements. 

If you’re not a fan of the streaks, try moving your plants to a shadier spot or covering them with a fabric row cover. Otherwise, enjoy your delicious, ripe banana peppers at harvesting time!