How to Plant, Grow, and Care for Poblano Peppers

Learn how to grow poblano peppers, and you can chow down on them all year long! If you’ve ever ordered a chile relleno, you know how delicious poblano peppers are! They’re smoky and mild and can be harvested fresh as poblanos or dried as ancho chiles to use in countless recipes. (But you’ll probably be growing poblano peppers for chiles rellenos, right?) 

Growing poblano peppers is pretty easy. If you’re familiar with growing chili peppers, bell peppers, jalapeños, banana peppers, or cayenne peppers, you already know the basics of growing poblanos since they’re all variations of the same pepper, the Capsicum annuum. With consistent moisture and plenty of sunlight, you’ll have peppers in no time.

Even if you’re not familiar with growing peppers, poblanos are a great choice to try for the first time. A poblano pepper will give you very few problems if you start them off strong. There are quite a few potential pests and diseases they’re susceptible to, but they’re easy to prevent and treat. Let’s get into how to grow them!

What is a Poblano Pepper?

Capsicum anuum ‘Poblano’ is part of a large group of peppers that are all the same species, but are incredibly different. This species ranges from spicy peppers like cayenne, to sweet peppers like bell peppers that aren’t spicy, and even other peppers like ornamental peppers.

Native Area

Poblano peppers are popular peppers from Puebla, Mexico. They stand out from others visually due to their heart-shaped fruit, which usually reaches about five inches in length and two to three inches wide. They’re mild on the spicy scale and have a great smoky flavor that tastes even better when smoked. 

Characteristics

You can harvest a poblano pepper green or red, with red being spicier. If you allow them to dry, you’ll suddenly have what are called ancho peppers that are great for turning into sauces. They are great in many dishes outside of sauces as well, especially because they are lower on the Scoville scale. 

If you don’t want to grow peppers that are high in Scoville heat units, poblanos are a great choice. Snag one from a local nursery and grow them under the cover of foliage next to where you grow tomatoes. Because they are self-pollinating, you won’t need more than one plant. You can have entire garden beds dedicated to Mexican cuisine, cultivating peppers, tomatoes, cilantro, and onions all in the same bed during the spring growing season. 

Varieties

Before you start planting seeds, you should know there are several types of poblano peppers out there that are worth trying. In the ‘Ancho’ range, the ‘Ancho Large Mexican’ peppers are long and wide, making them ideal for stuffed peppers. The ‘Ancho Mulato’ turns brown instead of red and has a more noticeable smoky flavor. The ‘Ancho Sweet Hybrid’ is long and slender, turns a bright red, and is considerably sweeter than other poblano pepper varieties.

Planting

If you live in USDA zones 9-11, you can start poblano pepper seeds outside in the ground. Peppers usually do better when transplanted, but direct sowing your pepper seeds is convenient. If you live in the ideal climate, you might as well try it out to see if it works for you.

To sow pepper seeds directly, wait until after the last frost date and grow in an area with fine soil free of large chunks. Make sure the area drains well so the seeds and seedlings won’t be waterlogged. Set the seeds in early spring in warm soil consistently above 70°F (21°C).

Set the poblano pepper seeds no deeper than a quarter inch deep and thin them to two inches apart when seedlings sprout. You’ll eventually need to thin each poblano pepper plant to 12 inches apart as it matures.

Planting seeds indoors to move outside follows similar guidelines. Grow your seeds in an area with plenty of light, preferably from a sunny window or grow lights, and use a heat mat if necessary to reach a soil temperature of 70°F (21°C). Provide a humidity dome to give the pepper seeds enough moisture. Start your seeds indoors about eight weeks before the final frost.

Plant two to three seeds in each section of a seed tray a quarter of an inch deep, and thin them out to one plant per pot once they sprout. You can wait until the spouts are a few inches tall and choose the strongest seedling for the best results.

When it’s time to transplant the seedlings, remove the humidity dome and your seed tray from the heat mat, and space the plants 12 inches apart, so there will be plenty of room for the mature peppers. 

How to Grow

Poblano peppers need plenty of sun and water, but how much is too much? Let’s get into the details so you can prevent accidents and properly care for them as they grow.

Light

Poblanos are sun-lovers that need warm temperatures to thrive. Nighttime temperatures should be consistently above 60°F (16°C) at a bare minimum, or warmer if possible. They like full sun, which is at least six hours of direct sunlight. 

The poblano pepper will need some extra care when the weather is extreme. In hot climates with intense summer heat, the plants will benefit from a shade cloth during the hottest part of the day to prevent sunscald on the leaves and fruits. In cool climates, it will need to be protected from cold temperatures.

Water

Growing poblano peppers need consistent watering to thrive. It’s important to keep the soil moist but not wet, which is why well-draining soil is a must! During the hottest parts of summer, you may have to water daily to make sure the soil doesn’t dry out too much. If the top inch or two dries out, they will be okay. You won’t have to water as often in the spring or fall since the temperatures are cooler.

To make watering easier, water at the base early in the morning or in the evening. This will allow the water to seep into the soil before the sun starts to evaporate it from the top layer and keep the soil damp. Your peppers will get a good drink and be encouraged to grow deep root systems.

Soil

It’s best to go about growing poblano peppers in soil that’s free of large chunks so the roots can easily make their way through it. Choose a soil that’s somewhere between sandy and loamy and doesn’t hold too much water. Basic potting soil is a great choice. It likes a somewhat acidic soil with a pH of 5.5-7.0.

For the best results, choose soil that’s rich in organic matter or amend it with compost. Give them a generous layer of mulch to retain moisture and prevent weeds from popping up. You can grow your peppers in a five-gallon pot, or larger pots with well-drained soil amended with well-rotted manure too. Ensure the containers have adequate drainage holes. Sandy soil meets the well-drained soil requirement and works well as long as it contains nutrition.

Temperature

Temperatures of 55°F (13°C) and below will slow the growth, and 32°F (0°C) will damage or kill them. Poblanos and other Capsicum annuum members can be grown as perennials in USDA zones 9-11, meaning they’ll come back for another season in the spring, or as annuals in zones 2-8. You can overwinter peppers in cold zones if you bring them inside when nighttime temperatures are consistently below 55°F (13°C) and put them under a grow light.

Fertilizing

Poblanos will benefit from fertilizer, especially if they’re growing in soil that isn’t at its peak. Poblano pepper seedlings usually need some fertilizer when they’re about four inches tall to help them develop a sturdy root system and strong limbs. At this stage, an all-purpose fertilizer with balanced nutrients will be great.

As they begin to get taller, you can fertilize them as needed, but it may not be necessary if they’re growing in nutrient-rich soil with compost or well-rotted manure. If you do fertilize them again, choose something that is low in nitrogen. Too much nitrogen will cause them to focus on leaf development instead of growing peppers.

Liquid fertilizer is recommended for growing poblano peppers because it makes it so they can easily access nutrients. Compost is also a great option because it will provide nutrients all season long.

Maintenance

Pepper pruning is pretty subjective among gardeners, and it certainly will depend on your growing conditions. Some insist all peppers must be pruned, while others say it’s unnecessary and negatively impacts the harvest!

One form of pruning that you may have heard of is topping off. This is when you cut off the top two or three nodes of your pepper to encourage bushy and compact growth. If your poblano seedlings had a rough start and grew a bit leggy, you may find topping off helpful to get it back to a fuller state. Topping off may not be necessary if they are short with several sturdy stems. If t has too many stems, you can trim those off, but be careful not to remove any flower buds or you’ll affect your harvest.

Poblanos can be overwintered, so you can keep them next year. To do this, remove every single leaf and cut it back to just a few nodes. The pepper should have a Y shape with just two little shoots of the main stem. It’ll look sad and hopeless, but those nodes are where the new growth will show up! Gardeners in zones 9 or warmer can keep their peppers in the ground, but everyone else will need to bring their peppers indoors and put them under a grow light. To prevent bringing pests inside, wash all the soil off of the root ball and put them in pots with new soil.

Some peppers may need supportive stakes to keep them standing upright, especially if they grow most of their peppers on the top.

Propagation

The easiest way to propagate peppers is to save the seeds by allowing them to dry out completely before storing the seeds in an envelope. Peppers grown from seeds can vary from their parents, but you can grow a clone from a cutting to make sure you get the exact same poblano peppers each time!

Poblano cuttings require patience because they take a while to form roots, but it’s an easy process. Cut a limb from your pepper plant that has two to three nodes and a few leaves. Place it in water and leave it for a couple of months, changing the water as needed. Once the roots are one to two inches long, you can transfer it to soil.

Grafting is also an option, but it’s still undecided if it’s more or less effective than other methods. Grafting is when you take a cutting of one and put it on another. While it may be worth looking into, it likely won’t benefit many backyard gardeners, especially if you live in an area where poblanos can only grow as annuals.

Harvesting

So you’ve grown poblano peppers – now it’s time to pick them and get them to your plate! Poblanos can be eaten fresh or dried and picked at your desired spiciness.

Poblanos are generally mild heat-wise, but they’re spicier, hotter peppers when red and less so when dark green. Pick fresh poblanos when they’re four to six inches long and are glossy. All you have to do is cut them from the stems with clean, sharp scissors. Then enjoy them in chili rellenos!

If you want dried peppers, also known as ancho peppers, allow them to turn red and dry out. You can let them dry on the pepper or hang them up in a sunny area.

Storage

Fresh poblanos will keep for up to a week in the refrigerator or up to a year in the freezer. To use them, let them come to room temp, and cook them as chili rellenos. Dried anchos will last up to a year or longer in the pantry, but try to eat them sooner rather than later or their quality will deteriorate over time.

You can also hot water can your poblano peppers, and keep them in sealed jars to use in cooking at a later time. Unsealed peppers last for up to 18 months. Opened jars should be used within a few days. 

Common Problems

Poblanos are easy to grow, but you may come across some problems eventually. Let’s look at what you can do about them!

Growing Problems

The most common problem for poblanos is water-related. Too much water will result in wilted or curled leaves, stunted growth, and deformed peppers. Too little water can lead to similar symptoms along with crunchy or brittle leaves. You can reverse the damage in the early stages, but you may need to relocate to a better area if you can’t fix it.

Nitrogen makes peppers grow more foliage, so if you have more leaves than peppers, they may be receiving too much nitrogen. If your peppers need fertilizer, choose something with little to no nitrogen to help them grow. 

On a similar note, blossom end rot is an issue that can crop up when there isn’t enough moisture in the soil for peppers to absorb the calcium needed to produce fruit. Ensure you’re watering enough to promote nutrient uptake. 

Pests

Beet armyworms and flea beetles eat leaves and can cause severe damage to young seedlings. You can prevent them with row covers and pick them off by hand as soon as you see them. Bacillus thuringiensis, or Bt spray, and neem oil can be effective against worms, as well as chemical pesticides.

Aphids eat sap and can cause curling leaves, or enough damage to kill the peppers in severe cases. Wash aphids off with water or treat them with a spray bottle that contains neem oil diluted in water. Insecticidal soap is another appropriate treatment.

Leaf rollers and spider mites use webs on peppers. Leaf rollers live up to their name, rolling leaves up and sealing them shut with webbing, making them easy to detect. Reduce their populations by keeping the area free of weeds, washing them away with water, or applying Bt. Be sure to spray the inside of rolled leaves since that’s where the leaf rollers live.

Tomato hornworms and pepper weevils eat them from the inside out. Tomato hornworms are susceptible to BT spray. Diatomaceous earth can be used to prevent pepper weevils.

Diseases

Diseases that your peppers may contract won’t always be able to be cured, but you can at least slow down the spread. Avoid getting leaves wet when you water and remove diseased parts. You can prevent most diseases by planting far enough apart so that their leaves won’t touch.

If you notice powdery mildew or downy mildew, remove damaged areas as needed. Apply neem oil or other horticultural oils. Prune for proper airflow to prevent spread to healthy tissue.

Heavy mottling on the leaves can indicate mosaic virus, which cannot be cured. In this case, remove the entire pepper and destroy it. MV is very contagious and can spread to other areas of the garden easily. 

If your peppers are dealing with late blights, you can remove damaged leaves and stem areas as they pop up. Those affected should be removed and disposed of entirely at the end of the season to reduce the potential for future spread. If it was a particularly severe outbreak of blight early in the season, solarize the soil in that area, and don’t grow other fruits and veg there for at least a season. 

Frequently Asked Questions