Why is My Poblano Pepper Plant Turning Purple?

It can be alarming if your poblano pepper plant starts to turn purple. Don’t worry! It’s not as big of a deal as you might think.

Your poblano pepper plant is turning purple because it has an excess of anthocyanin, the compound responsible for the color purple in plants. Anthocyanin is non-toxic and won’t affect whether or not you can eat your poblanos. The color change is caused by excess anthocyanin, resulting from a phosphorus deficiency or extreme weather.

Keep reading to learn all about poblano pepper plants turning purple!

Reasons for the poblano pepper plant to turn purple

First, let’s talk about the reasons why your plant may be turning purple.

Reasons for a poblano pepper plant to turn purple include:

  • Phosphorus deficiency
  • Extreme weather
  • Excess anthocyanin

A phosphorus deficiency is often caused by a lack of nitrogen rather than a lack of phosphorus. A nitrogen deficiency prevents plant roots from absorbing phosphorus, leading to a deficiency.

Extreme weather can cause poblano pepper plants to turn purple. Extreme weather includes, but is not limited to, excessive heat, freezing temperatures, and drought.

Lastly, all purpling of plants is due to a compound called anthocyanin. This is what makes plants appear purple. Extra anthocyanin will cause a purple appearance on your poblano pepper plant. Luckily, it’s a non-toxic compound!

Phosphorus deficiency

If your poblano plant is turning purple, you may have a phosphorous deficiency on your hands.

One reason why your poblano pepper plant is turning purple may be a phosphorus deficiency. Along with purpling, phosphorus deficiencies can also cause reduced shoot growth.

Phosphorus is one of the most important elements for plants. Phosphorus deficiencies can cause reduced shoot growth and the purpling of leaves.

How to fix it: 

A deficiency can’t be good! How do you fix it?

To fix a phosphorus deficiency, make sure your soil has enough nitrogen. A nitrogen deficiency can inhibit the uptake of phosphorus. Use a fertilizer with an NPK value of 5-10-10 to ensure that your poblano pepper plant has the right ratio of nitrogen, phosphorus, and potassium.

A lack of phosphorus in the soil doesn’t always cause phosphorus deficiency. Instead, it’s usually caused by a nitrogen deficiency that prevents your poblano’s roots from absorbing enough phosphorus.

Be sure to use a fertilizer with a 5-10-10 NPK value to make sure your peppers have both enough nitrogen and phosphorus.

The NPK value is the percentage of nitrogen, phosphorus, and potassium found in fertilizer. These are potentially the most important elements when it comes to plant growth.

Always research the NPK value needed by a plant before fertilizing it!

Extreme weather

There’s not much you can do to avoid extreme weather if you’ve planted at the right time of year.

One reason why your poblano pepper plant is turning purple may be extreme weather, including excessive heat, freezing temperatures, and drought.

Weather that’s too hot can cause a purple color in plants.

Other extreme conditions that can cause purpling include freezing temperatures and drought.

How to fix it: 

Now what?

You can’t fix extreme weather. All you can do is follow proper transplanting advice- transplant when nighttime lows are regularly above 50°F. Besides that, all you have is a hope and a prayer!

Well, you can’t really fix this one. 

The best you can do is to transplant your poblano peppers when nighttime lows are regularly above 50°F.

If you follow that advice, the only other thing you’ve got is hope and a prayer!

Excess anthocyanin

What the heck is anthocyanin?

If your poblano pepper plant is turning purple, that means it has an excess of anthocyanin. Anthocyanin is the compound that causes plants to appear purple. It’s a non-toxic, water-soluble glucoside and isn’t much of a concern.

Anthocyanin is a water-soluble glucoside that causes plants to turn purple.

While this isn’t a “cause” on its own, it’s the reason behind the purpling of plants – normal or not.

How to fix it: 

To avoid excess anthocyanin, make sure your poblano peppers have enough phosphorus and nitrogen.

Likewise, transplant your poblanos when nighttime lows are consistently above 50°F.

Are purple poblano peppers safe to eat?

Now the real question is…can you still eat the peppers?

Purple poblanos peppers are still safe to eat. Anthocyanin, the compound that causes purpling in plants, is non-toxic.

Don’t worry, you can still eat the poblano peppers off of a purple poblano pepper plant! It won’t harm you.

The only real concern is how the causes behind the purpling will affect your plant’s growth.

But as for the fruits themselves, no worries!