If you’ve noticed dark patches on your peppers, you’re probably wondering why are my jalapenos turning black. This discoloration can be alarming, but it’s not always a sign of trouble. In many cases, it’s a completely natural part of the plant’s growth process.
This guide will walk you through all the common causes, from harmless ripening to serious diseases. You’ll learn how to tell the difference and what you can do about it. Let’s look at what might be happening in your garden.
Why Are My Jalapenos Turning Black
First, don’t panic. A black jalapeno isn’t necessarily a bad jalapeno. The cause can range from a simple genetic trait to a fungal infection. Identifying the correct cause is the first step to managing it.
Here are the primary reasons your jalapenos might be developing black colors:
- Natural Ripening and Genetics
- Sunscald
- Blossom End Rot
- Bacterial or Fungal Diseases
- Temperature Stress
- Pest Damage
1. Natural Ripening & The “Black Jalapeno” Variety
This is the best-case scenario. Many jalapeno varieties develop dark purple or black streaks as they mature. This is caused by anthocyanins, the same pigments that make blueberries blue and eggplants purple.
It’s a natural sunblock and antioxidant for the plant. Peppers like ‘Purple Jalapeno’ or ‘Black Pearl’ are bred specifically for this trait. Even standard green jalapenos can show black caps or streaks before turning red.
How to tell: The blackening is even, often shiny, and the pepper feels firm and healthy. It usually starts at the shoulders (where the pepper meets the stem). The plant itself will have vibrant green leaves.
What to do: Nothing! Enjoy the show. The pepper is perfectly edible and will continue to ripen to its final color, usually red.
2. Sunscald (Sunburn)
Just like our skin, pepper fruits can get sunburned. This happens when they are suddenly exposed to intense, direct sunlight, often after a period of shade or if foliage is lost.
The affected area turns white, yellow, or pale brown first, then can soften and turn black as secondary rot sets in. It’s most common on the side of the pepper facing the sun.
How to tell: The spot is flat, papery, and sunken. It appears on the most exposed surface. The rest of the pepper and plant looks fine.
What to do:
- Harvest any severely damaged peppers to prevent rot.
- Provide afternoon shade with a shade cloth if you live in a very hot climate.
- Avoid over-pruning your plant, as leaves provide natural shade for the fruits.
3. Blossom End Rot
This is a common garden issue, but it’s often misunderstood. Blossom end rot is not a disease; it’s a physiological disorder caused by a calcium deficiency in the developing fruit.
However, this is rarely due to a lack of calcium in the soil. Instead, it’s caused by inconsistent watering, which prevents the plant from uptakeing calcium properly.
The rot always starts at the blossom end (the bottom tip) of the pepper. It begins as a water-soaked spot that enlarges, turns dark brown, and becomes leathery and sunken.
How to tell: A dark, dry, sunken lesion at the very bottom of the fruit. It can affect multiple peppers on the plant.
What to do:
- Ensure consistent, even watering. Don’t let the soil dry out completely, then flood it.
- Mulch around plants to help retain soil moisture.
- Avoid excessive high-nitrogen fertilizers, which promote fast leaf growth at the expense of fruit health.
- Remove affected peppers so the plant can focus it’s energy on new, healthy fruit.
Identifying Bacterial and Fungal Diseases
When black spots are caused by disease, they often look different than environmental issues. You’ll usually see other signs on the leaves and stems too.
4. Bacterial Spot
This is a serious bacterial disease that thrives in warm, wet weather. It spreads easily through splashing water or by touch.
On fruits, it starts as small, raised, scabby spots that are green and blister-like. They eventually turn brown or black and become rough and cracked. Leaves will have small, yellow-ringed spots that turn brown and make the leaf look tattered.
How to tell: Raised, scabby, cracked spots on fruits combined with spotted, damaged leaves.
What to do:
- Remove and destroy all infected plant parts immediately. Do not compost them.
- Water at the base of the plant, not overhead, to keep leaves dry.
- Space plants for good air circulation.
- There is no cure, so prevention is key. Use disease-free seeds and rotate crops yearly.
5. Anthracnose (Ripe Rot)
This fungal disease is a major cause of fruit rot. It often doesn’t show up until the pepper is nearly ripe or after harvest.
It creates circular, sunken spots with dark centers. Inside, you might see a concentric ring pattern and a mass of salmon-colored spores in wet weather. The spots can quickly spread and ruin the entire fruit.
How to tell: Circular, sunken, wet-looking rot, often with colored spores in the center. It can appear anywhere on the fruit.
What to do:
- Harvest peppers as soon as they are ripe; don’t let them over-mature on the plant.
- Remove any infected fruits and plant debris from the garden.
- Apply a fungicide labeled for anthracnose on vegetables as a preventive measure if you’ve had problems before.
- Again, crop rotation is essential.
6. Temperature and Environmental Stress
Peppers love warmth, but extreme conditions can cause problems. Cold nights below 50°F (10°C) can stunt growth and cause purpling or blackening of stems and sometimes fruit.
Conversely, very high heat can stress the plant, leading to poor fruit set and discoloration. The plant may abort flowers or young fruits, which can then turn black and fall off.
What to do: Protect young plants with cloches or row covers if cold snaps are forecast. In intense heat, use shade cloth and ensure consistent watering to help plants cope.
7. Pest Damage That Leads to Rot
Insects like aphids, flea beetles, or caterpillars can create tiny wounds on the pepper’s skin. These small injurys become entry points for rot-causing bacteria and fungi.
You might see a small hole or scar that’s surrounded by a spreading black or mushy area.
What to do: Practice regular pest control. Inspect plants often and manage pests with insecticidal soap, neem oil, or by hand-picking. A healthy plant is more resilient.
Quick Diagnosis Guide: Is It Bad?
- It’s PROBABLY NATURAL if: The pepper is firm, the black is even and often shiny, the plant is healthy, and the blackening starts at the stem end.
- It’s PROBABLY SUNSCALD if: The spot is flat, papery, and on the sun-facing side of the fruit.
- It’s PROBABLY BLOSSOM END ROT if: The lesion is dry, sunken, and strictly at the bottom tip of the pepper.
- It’s PROBABLY DISEASE if: Spots are raised, scabby, or sunken with spores; leaves also have spots; or the rot is wet and spreading fast.
Prevention is the Best Medicine
Most causes of black jalapenos can be prevented with good gardening practices:
- Water Wisely: Use drip irrigation or soaker hoses. Water deeply and consistently, aiming for 1-2 inches per week. Mulch to conserve moisture.
- Feed Balancedly: Use a balanced, slow-release fertilizer or one formulated for tomatoes and peppers. Avoid too much nitrogen.
- Promote Airflow: Space plants properly and stake them. Good airflow keeps leaves dry and discourages fungal diseases.
- Practice Crop Rotation: Don’t plant peppers, tomatoes, or eggplants in the same spot year after year. Wait at least 2-3 years before replanting solanaceous crops in that bed.
- Choose Resistant Varieties: Start with healthy, disease-resistant plants or seeds from a reputable source.
- Inspect Regularly: Catching a problem early makes all the difference. Remove any problematic leaves or fruits immediately.
FAQ: Your Questions Answered
Q: Can I eat a jalapeno that has turned black?
A: It depends on the cause. If it’s natural ripening (firm, shiny), yes! If it’s sunscald or blossom end rot, you can cut off the affected part and eat the rest. If it’s a fungal or bacterial disease, it’s safest to discard it.
Q: Are black jalapenos hotter?
A: Not necessarily. Heat level is more related to the variety, growing conditions, and maturity. A ripe red jalapeno is often sweeter and sometimes hotter than a green one, but color alone isn’t a reliable heat indicator.
Q: My jalapeno plant stems are turning black, is that related?
A: Blackening stems can be a sign of a more serious disease like bacterial canker or phytophthora blight. It’s often separate from fruit discoloration and requires immediate removal of the plant to prevent spread.
Q: Will a pepper recover from blossom end rot?
A: The specific affected pepper will not heal. However, with consistent watering and care, the plant can produce new, healthy peppers that are free of the disorder.
Q: How do I stop my jalapenos from getting black spots?
A> Focus on prevention: consistent watering, balanced fertilizer, good spacing for air flow, and using clean mulch. Also, try to keep the foliage as dry as possible when you water.
Seeing black on your jalapenos is a signal from your plant. By learning to read that signal, you can determine wether it’s a beautiful natural process or a call for help. Most often, with a little adjustment to your watering or plant care, you can get back on track to a healthy, productive harvest.