Pepper Fertilizer: How And When To Fertilize Peppers

Pepper Fertilizer: How And When To Fertilize Peppers

By: Mary Ellen Ellis

Peppers are popular in the vegetable garden. Hot peppers and sweet peppers alike are versatile and store well. They’re great additions to any garden growing veggies. To get the most out of your plants, choose the right pepper fertilizer and fertilizing program.

Best Fertilizer for Pepper Plants

The best fertilizer for your pepper plants depends on your soil. It’s a smart idea to get it tested to find out the nutrient content before making amendments. However, adding compost to the entire vegetable bed prior to planting is always a good idea too.

Generally, a balanced fertilizer works for peppers. But if your soil testing shows you have enough phosphorus, you should choose a low- or no-phosphorous fertilizer. Nitrogen is particularly important for stimulating good pepper growth, but you have to know the best time to fertilize peppers to get the best results.

When to Fertilize Peppers

First, broadcast the soil with a general fertilizer or compost before you put any plants in the ground. Then, front load the plants with nitrogen for optimal growth. Adding the right amount of nitrogen will stimulate stem and foliage growth so that your pepper plants will grow big enough to support several fruits each.

Expert gardeners suggest you add your nitrogen fertilizer on this schedule:

  • Apply about 30 percent of the nitrogen as part of the pre-planting broadcast.
  • Two weeks after planting, add 45 percent of the nitrogen.
  • Save the last 25 percent for the final weeks as the pepper harvest is wrapping up.

Importance of Staking Pepper Plants

In addition to more and bigger fruit, a consequence of fertilizing pepper plants is that your plants will grow bigger. Pepper plants are not able to stay erect on their own at a certain point, so be prepared to start staking peppers as they grow.

For a row of peppers, place stakes between each plant. Tie several parallel strings between each stake to provide the support the plants need to stay upright. If you only have a few plants or potted peppers, just adding a stake and zip ties to each plant should be adequate.

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Adding More Fertilizer to Peppers

Peppers, eggplant, and okra are fairly big eaters, but they don't like their nourishment all in one dose. Sidedress them a few times during the growing season. Side-dressing is working a small amount of fertilizer into the soil three inches from the plants' stems to provide them with a steady diet. It's very easy to do, and the reward is a good crop.

Use a fertilizer such as dried manure, cottonseed meal, or a balanced commercial fertilizer such as 5-10-10. When you're selecting fertilizer for these crops, be sure it doesn't contain too much nitrogen. The lush foliage nitrogen encourages is great for plants like lettuce, but when other plants are putting their energy into making greenery, they're not making fruits. It's better to have the food on the table!

Peppers, eggplant and okra should get their first side-dressing around blossom time, usually a month after they've been put outside. Sidedress again about a month later, after the first fruits have developed. This helps the plants keep producing by giving them a little extra boost after all that work.

To sidedress, dig a trench around the plant about one inch deep and three to four inches away from the stem around the drip line of the leaves (see below). Put a handful of manure or compost or two to three tablespoons of a balanced fertilizer in a band in the trench. Cover the fertilizer with soil. If the plants are in rows, dig a shallow trench, one to three inches deep along either side of the row, again at the drip line of the leaves. Then sprinkle a band of balanced fertilizer in the trench, using about 1/2 cup per 10 feet of row, or a layer of manure about one inch deep along the length of the row. Cover that with soil, too.

No matter whether you use the circular-trench or row-trench method, be careful not to sprinkle any fertilizer on the plants as it will burn them. Next, water the soil to send the fertilizer down to the roots.

When water falls onto a plant, it drips off the leaves. The circle on the ground made by water dripping off the plant's outermost leaves is called the drip line. Its diameter will vary with the size of the plant: the bushier the plant, the bigger the drip line. You can also determine the drip line by the plant's shadow. When the sun is right above the plant, look at the shadow on the ground cast by the leaves. The outer rim of the shadow will be about the same as the drip line.

Peppers require nitrogen, phosphorus, potassium, and a little bit of magnesium in order to grow properly.

A 5-10-10 fertilizer is best for fertilizing peppers. This means that the fertilizer contains 5% nitrogen, 10% phosphate, and 10% potassium.

If you are using a fertilizer that you dissolve in water first and then spray on your garden plants, then make sure to spray the fertilizer at the base of the plants and not at the tops of the plants. Wet leaves and branches are more likely to develop diseases.

After you fertilize your plants, lay a layer of mulch around the base of the plants, such as grass clippings or leaves. Mulching will help keep weeds down and help prevent moisture evaporation.

Fertilize your peppers once per month or as directed on fertilizer package.

In between fertilizer treatments, approximately every 2 weeks, you can spray this homemade epsom salt fertilizer on your plants to help prevent magnesium deficiency in your plants.

MSU Extension

Adequate plant growth prior to fruit set is important for economic pepper production. If you’re fertilizing to maintain plant growth and good size fruit, you will also have to stake and tie to maintain quality.

Double row, staked and tied peppers. Photo by Ben Phillips, MSU Extension.

There are probably as many pepper fertilization programs as there are pepper growers, and that’s OK. However, there are some things to remember no matter who designs the program. According to Michigan State University Extension, most fresh market peppers are currently grown using plasticulture techniques, including fertilizing through the drip system. There are two basic aspects that should be followed when fertilizing peppers: staking and tying, and nitrogen.

Staking and tying

Unlike their relative the tomato, peppers will respond to more nitrogen by producing more fruit – at least to a point. Peppers can be over-fertilized, which can delay flowering and fruiting. However, with good rates and timing, more nitrogen can translate to more fruit and thus, higher yields. The problem with more fruit is the pepper plant is not capable of staying erect with the extra fruit load. The plant will fall over, potentially exposing fruit to sunburn and placing it in contact with the ground or plastic, reducing quality.

If growers increase fertilizer rates, especially nitrogen, it is important they stake and tie so plants stay erect. Peppers on plastic are generally planted in two row beds. Some growers stake and tie each row, similar to a single row of staked tomatoes (see photo). Other growers will place stakes in each row, but only put the string around the outside of the two rows, keeping the peppers from falling into the walkway but allowing them to support each other between the two rows. Either way keeps the plant fairly erect – protecting the fruit.

Front load nitrogen

What I mean by front load nitrogen is that it is important to apply most of your nitrogen prior to first fruit set. Many annual fruiting plants like peppers will slow vegetative growth once they set fruit. The plant’s main goal is to make fruit and once that fruit is set it gets the idea that its job is done and shifts energy from plant growth to fruit growth. That may be good for that one fruit, but as a grower you need to have more than one marketable fruit per plant.

I’m sure you have seen pepper plants that look like sticks with a dozen leaves and two or three fruit. To avoid this, enough fertilizer has to be applied prior to fruit set so sufficient plant growth is produced prior to adding a fruit load. Once a larger plant is produced, it has enough leaf area (energy producing area) to carry a fruit load and continue vegetative growth.

I am sure many pepper growers have noticed their pepper plants put on new growth after first harvest. That’s because an energy sink (fruit) has been removed and freed up energy to allow the plant to shift it to making new vegetative growth. The goal is to get enough plant growth initially so these growth starts and stops are minimized.

Actual nutrient amounts vary from site to site and plant population, but for most situations all phosphorus (P) and potassium (K) can be broadcast prior to bed formation and planting. Nitrogen (N) should be split with part applied as a broadcast and the rest through the drip system. With this approach for N, I recommend applying 30 percent pre-plant as a broadcast, and then beginning two weeks after planting apply 45 percent of the N through the drip system spread out over the four or five weeks until the first fruit begin to swell. The final 25 percent is a maintenance level and should be spread out and applied on a weekly basis through the drip system until two weeks prior to last harvest. This approach will develop enough plant prior to fruit set that will allow the plant to continue to flower and size fruit.

This article was published by Michigan State University Extension. For more information, visit https://extension.msu.edu. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464).

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Best Fertilizer for Tomatoes and Peppers

  • Hand-crafted, high-performance liquid fertilizer for all large vegetables. 4.0- NPK.
  • Super-concentrated: 256:1. One gallon makes 256 gallons of full-strength nutrient. One tablespoon
  • For hand-watering, drip, hose-end, foliar, soil, containers, hydroponics.
  • Made from organic teas, mycorrhizae, worm casts, humic acid, kelp, enzymes, and minerals.
  • Calcium rich. No more blossom-end rot.

Video Guide for Growing Tomatoes and Peppers

#1. What’s the best tomato fertilizer formula? It’s recommended to use 4-18-38 together with Magnesium Sulfate (Epsom Salt) and Calcium Nitrate for the ultimate balanced water-soluble fertilizer.

#2 What the best tomato fertilizer ratio? According to Rabbit Hill Farms, the ideal ratio for is 2-1.5-3 Total Nitrogen (N) 2% Available Phosphate (P2O5) 1.5% Soluble Potash (K2O)3%.

#3. What the best natural fertilizer for tomatoes? You’d be surprised what tomatoes like but to keep things simple here a list of 3 natural ways you can fertilize tomato plants. 1. Coffee grounds. (Acid) 2. Eggshell (Calcium). 3. Banana leaves (Potassium). For more natural ways to fertilize your plants, you can reference this guide.

#4. What the best liquid fertilizer for tomatoes? Everyone loves Miracle Gro but there are a few liquid fertilizers listed above that are good alternatives.

#5. Is adding Epsom salt to the soil good for peppers? Yes, adding a couple of tablespoons when preparing the soil for planting is a good best practice.

#6. How often should I fertilize my plants? First, fertilize the soil when you’re planting (granules or solid). Then, fertilize again after the plant forms – about the size of a fingertip (liquid). And then, fertilize again when the tomatoes or peppers begin to ripen (liquid). Finally, every 7 – 10 days until you pick them (liquid). For more information please reference this guide.

#7. What’s the best fertilizer?

The best fertilizer for peppers and tomatoes is whatever works best for your plants.

No Magic Formula…

I wish there was a magic formula for everyone to use but it varies depending on the climate, soil, geography, moisture, and the care your plants get.

So regardless which fertilizer you decide to buy or use, it all comes down to you taking care of your plants: water, feed, and deal with insect issues, and in no time – you’ll be harvesting enough tomatoes and peppers to make lots of salsa.

Chili Pepper Growing Tips

For successfully growing peppers, keep these growing tips in mind.

Do Not Over Water Your Pepper Plants

Pepper plants love their water, of course, and they need a steady supply, but peppers won’t grow well in overly saturated soil. It waterlogs their roots. Use soil that retains moisture yet has proper drainage. Mulch is useful to prevent water evaporation.

If you are uncertain about watering, don’t. Never over-water. Most diseases and growing problems are due to overwatering.

Do Not Overfertilize Your Pepper Plants

Using a lot of fertilizer may help the pepper plant to develop bright leaves and flowers, but hinders pepper production. A good 5-10-10 fertilizer is usually sufficient for peppers. Work it into the soil before transplanting. We use a solution of fish emulsion and seaweed.

Pinch Your Pepper Plants for Bushier Plants

When the pepper plant is about six inches high, clipping the growing tip will result in a bushier plant. Remove any flowers that appear early, as the early flowers diminish the plants overall energy.

Got any further questions? Ask away! I’m happy to help. Feel free to contact me anytime and I will do my best to answer your questions. — Mike H.