Do Poblano Peppers Need Fertilizer? (With Proper Timing & Frequency)

Fertilization is an intimidating topic. You likely know that it’s important, but many gardeners slack on it- whether they think their garden is doing just fine or they’re too overwhelmed to know where to begin.

Poblano peppers need fertilizer upon transplant and 2-3 times throughout the season or using an extended-release fertilizer. Peppers enjoy an NPK value of 5-10-10. There are many signs that your poblanos may need to be fertilized, although it’s easy to mistake them for signs of underwatering or sunburn. 

Keep reading so you can give your poblano peppers the love they deserve!

Do you need to fertilize poblano peppers?

Many gardeners think they can get away with just planting something and forgetting about it. Truth be told, some plants thrive off of neglect. But poblano peppers aren’t one of them!

You need to fertilize poblano peppers. Fertilizers aid in all aspects of plant growth. Fertilization is especially important for fruiting plants like peppers. Poblano peppers like fertilizers with an NPK value of 5-10-10.

Fertilizers are vital for growing healthy, happy poblano peppers. Fertilizer helps with all aspects of plant growth, including:

  • Budding
  • Flowers
  • Fruiting
  • Producing seeds
  • And more

Plants need a lot of energy to produce fruit. Think about it- they still have to grow their root systems, stems, and leaves too. Plants can’t drop all of their other responsibilities just because they’re fruiting!

But before you choose a fertilizer, you need to know a little bit about them.

The NPK value of a fertilizer is the ratio between the fertilizer’s nitrogen, phosphorus, and potassium. It also doubles the fertilizer’s percentage of nitrogen, phosphorus, and potassium.

Pepper plants like fertilizers with an NPK value of 5-10-10, although 10-10-10 fertilizers also work. Truthfully, most gardeners develop their own opinions and preferences about the NPK values of their fertilizers. 

This is likely because most gardeners don’t check the nutrient levels that their gardens already have, so it makes sense that some gardens would need more of one nutrient than another- even if a specific NPK value is suggested for a crop.

Tips for fertilizing your poblano peppers

Now that we’ve established how important fertilization is, let’s go over some tips and tricks so you have the inside scoop.

Tips for fertilizing your poblano peppers include: using less fertilizer in heavier soils than in light soils, not fertilizing germinating seeds, fertilizing once your peppers develop their first true set of leaves, using ¼ or ½ strength fertilizer on young plants, and using slow-release fertilizers throughout the season.

The amount of fertilizer you should use depends on many factors such as the kind of fertilizer you’re using, the original soil you’re working with, and how much square footage your garden has. 

For example, loam and heavier soils require less fertilizer than light or sandy soils. This is because there are already more nutrients in the soil naturally, and therefore less need to supplement with additional nutrients.

Generally speaking, you never fertilize seeds while they’re germinating. 

Start fertilizing after your poblano plant sprouts and develops its first set of true leaves. Initial fertilization should only be ½ strength to avoid burning your young plants or overwhelming them with too many nutrients at once.

If you buy a seedling from the nursery, apply the ½ strength fertilizer when you transplant it for initial fertilization. After that you will do best with a slow-release fertilizer.

Fully potted and well-established poblano peppers from nurseries should only need the application of a slow-release fertilizer.

While this is all fine and dandy, we all know that nature has a mind of its own. In other words, “following the rules” doesn’t always cut it when you’re gardening.

Since mother nature has so many tricks up her sleeve, we need to have tricks up our sleeves as well. So let’s talk about how to know if your poblano pepper plants need additional fertilization.

Signs that your poblanos need fertilizer

Knowing the signs and symptoms of your poblanos need for fertilizer is important. The tricky thing is distinguishing these symptoms from other causes like overexposure to the sun or underwatering. But with a little experimentation, you’ll get it right!

Signs that your poblanos need fertilizer include: yellow leaves, stunted growth, brown leaves, tip burn, end rot, and spindly growth. It can be hard to distinguish if these symptoms point to under-fertilization or are due to under- or over-watering, the wrong amount of sun exposure, or pests.

A few things can go wrong when you’re growing poblano peppers. Some instances include not getting enough sun, being over or under-watered, or getting pests.

Beyond these things, nutrient deficiencies can be another source of your plant’s woes.

Let’s talk about what it looks like if your poblano peppers are lacking a specific nutrient.

  • Nitrogen deficiency – Yellow lower leaves. Too much nitrogen can cause excessive leaves and low fruit yields.
  • Phosphorus deficiency – Stunted growth. Purple-reddish tint on leaves.
  • Potassium deficiency – Brown leaves along the edges, beginning with older leaves.
  • Calcium deficiency – Leads to the famous “tip burn” and end rot. 
  • Sulfur deficiency –Stunted and spindly growth. Yellowing leaves.

Even if you’re already fertilizing your poblano pepper plant, these symptoms can be signs that you need to add an additional boost of a specific nutrient to the regimen.

When do you fertilize poblano peppers for the first time?

Now that you know a little bit more about fertilization, let’s discuss the finer details.

You fertilize poblano peppers for the first time when they develop their first true set of leaves or when you transplant them. Use a ¼ or ½ strength fertilizer to avoid overwhelming your young plants with too many nutrients. Don’t fertilize germinating seeds.

This next section will break down multiple scenarios and walk you through first-time fertilization.

Growing from seed

Some people enjoy nothing more than seeing something go from seed to table. But do you fertilize the seeds? Or when the peppers sprout? What’s the deal?

When growing poblano peppers from seed, don’t fertilize them until they’ve developed their first true set of leaves. Fertilize at ¼ or ½ strength to avoid burning your young plants. Use slow-release fertilizers throughout the season.

Don’t fertilize your poblano peppers until they’ve sprouted. Once they’ve developed their first true set of leaves, fertilize at half strength, so you don’t shock or burn your young plants. 

If you’re using dry fertilizer, place it about 3”-4” around the pepper stems.

Fertilize your peppers again 2-3 times throughout the season. You can also choose to use a slow-release fertilizer. This will keep nutrient levels consistent, and is also great if you’re on the forgetful side!

Buying plants from the nursery to transplant

Most poblano owners buy small plants early in the season to transplant into their own garden.

When buying poblano peppers plants from the nursery to transplant, fertilize them for the first time when you plant them. Use half-strength fertilizer at first to avoid shocking them. After that, use slow-release fertilizers throughout the season.

Fertilize your peppers for the first time when you transplant them. Initial fertilization should be half-strength to not shock your young plants with too many nutrients.

If your fertilizer is dry, place it 3”-4” around the stems.

Fertilize again 2-3 times throughout the season. You can also use a slow-release fertilizer to keep nutrient levels consistent.

Buying a potted pepper

On the other hand, you can just buy a fully potted pepper plant, and you’re good to go!

When you buy a potted poblano pepper plant, fertilize it 2-3 times or use slow-release fertilizers throughout the season.

Since your pepper is already planted and growing, there’s no need for initial transplant fertilization. Fertilize your potted pepper 2-3 times throughout the season. If you prefer, you can opt for a slow-release fertilizer to keep nutrient levels consistent.

How often should you fertilize poblano peppers?

If you’re going to fertilize your poblano peppers, you might as well do it right!

Fertilize your poblano peppers once they’re transplanted with a ¼ or ½ strength fertilizer. Then fertilize 2-3 times throughout the season. You can also use a slow-release fertilizer instead. Poblano peppers prefer fertilizers with a 5-10-10 NPK value.

If you live in the southern states, pruning your peppers in late fall while adding additional fertilizer can prolong your poblano pepper production.

Can you fertilize poblano peppers too much?

Don’t go overboard!

You can fertilize poblano peppers too much. Excessive fertilization can lead to too much leaf growth, low fruit yields, leaf tip burn, and more. It’s important to use ¼ or ½ strength fertilizer on young plants, so you don’t overwhelm them with too many nutrients.

You can fertilize poblano peppers too much. Excess nitrogen can lead to too much leaf growth and low fruit yields. Likewise, leaf tip burn can be a result of too much fertilizer. 

Another sign of overfertilization is thick, green, and yellow curling leaves that seemed to pop up overnight.

Fertilizing your plants at full strength while they’re still young can overwhelm them, which is why you should always use ¼ or ½ strength fertilizer on young plants.

What is the best kind of fertilizer for poblano peppers?

How do you know what to buy with so many different fertilizers on the market?

The best kind of fertilizer for poblano peppers is a low-strength initial fertilization upon transplant, followed by 5-10-10 NPK extended-release fertilization. There is no significant difference between inorganic and organic fertilizers in terms of pepper health or production. That being said, organic fertilizers are better for the environment.

Let’s break down the difference between inorganic fertilizers and organic fertilizers.

  • Inorganic fertilizers – Can deliver nutrients rapidly in liquid form or come in a slow-release form. Tend to be cheaper. Easier to calculate precise nutrient values. Have a higher potential to burn plants. Have a higher potential for leaching or runoff.
  • Organic fertilizers – Are typically slow-release. Soil microorganisms transform the nutrients into forms that are bioavailable to your peppers. Are usually more expensive. Lower burn potential and less likely to leach or runoff. Improperly composted manure can contain weed seeds or human pathogens.

Most studies prove that growth, yield, and macronutrient content are all improved by fertilization- but there is no significant difference in these results between inorganic and organic fertilizers.

Just because it’s “common knowledge” that organic fertilizers produce happier plants doesn’t mean it’s true.

However, the belief that organic fertilizers are better for the environment in general certainly withstands the tests of science. Overusing inorganic fertilizers can lead to runoff, erosion, contaminated water, and disruptions to aquatic life.

Regardless of organic or inorganic, poblano peppers do best with a low-strength initial fertilization upon transplant followed by extended-release fertilizers throughout their lifetime.