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Coffee Grounds a Helpful or Harmful Additive to Pepper Plants?

Pepper plants are relatively easy to grow, but many things can go wrong during the process, which will dramatically hinder their yield. Thankfully, many tricks can be used to maximize the growth potential of your pepper plant. One old gardening method is to add coffee grounds to your fertilizer, but are coffee grounds good for pepper plants?

Coffee grounds are good for pepper plants but should be used sparingly. Coffee grounds contain high levels of nitrogen, which can give your pepper plants a boost. It is recommended that you employ used coffee grounds when fertilizing your pepper plants because they have less caffeine and acidity.

This article will explore why coffee grounds are good for pepper plants and what the nutrients they can provide. We will also go over how to prepare the coffee grounds for use with a pepper plant and identify the best growth stage to introduce the grounds. By the end of this article, you will have all the knowledge required to grow the best peppers this season, so read on.

Photo by Chernetskaya

Are Coffee Grounds Good for Pepper Plants?

Coffee grounds are a great fertilizer additive for pepper plants.

Sometimes, a lack of certain nutrients in a pepper plant’s soil can cause its growth to become stunted and might even kill it.

Adding coffee grounds to a pepper plant’s soil mixture can revitalize and rejuvenate the plant, restoring its life and vitality and allow it to grow and flourish as nature intended.

Worms also enjoy coffee grounds, and they will help to fertilize your soil even further, so it is a win-win situation.

Many who are just learning of this trick for the first time will probably be wondering why exactly it is that coffee grounds can be so good for pepper plants. Let us delve a little deeper into the technical elements to find out why this is.

What Key Nutrients do Coffee Grounds Give Pepper Plants?

Coffee grounds can provide a wide range of essential nutrients that plants need to grow healthily.

Coffee grounds contain and provide plants a good amount of the following nutrients:

  • Potassium
  • Calcium
  • Zinc
  • Iron
  • Phosphorus
  • Copper
  • Nitrogen

The most sought-after nutrient in coffee grounds by gardening enthusiasts is nitrogen.

Coffee grounds are not good for all plants because not all plants benefit from excessive nitrogen levels, but peppers in particular benefit greatly from the introduction of additional nitrogen.

It is important to note that the nitrogen in coffee grounds is not immediately available and takes time to be released. This slow-release nature makes coffee grounds great for pepper plants in the long term but less effective if you’re looking for immediate results.

Photo by Keechuan

Should the Coffee Grounds Given to Pepper Plants Be Fresh or Used?

Now that we know that coffee grounds are good for pepper plants and we understand the nutrients they provide, we will now look in to the best way to apply them to plants.

The coffee grounds that you use to fertilize your pepper plants should be used.

Used grounds, because they have already been broken down, will likely produce better and faster results in your garden than brand new grounds could.

Using new coffee grounds for your soil would be rather wasteful. Dedicated coffee drinkers are certainly not hard to find, and more often than not, they simply throw their used grounds in the trash. Coffee drinkers, as well as local coffee shops, would likely be glad to let you take their old used ground off their hands.

New coffee grounds can be used and should not cause too much problem, but they tend to be much more acidic, so used grounds are recommended. Used grounds have less acidity and are typically neutral.

Do Coffee Grounds Need to be Composted Before You Add Them to Pepper Plants?

Coffee grounds do not need to be composted before they are added to your pepper plants.

Coffee grounds can be used in many different ways for gardening and for a multitude of different reasons. They can be immediately mixed into the soil of your pepper plants and used as fertilizer.

Some gardeners will use coffee grounds as mulch, and others have even been known to mix grounds with water to create a liquid mixture to be poured on plants.

Coffee grounds can also be used, in some cases, to repel harmful bugs and insects from a garden.

With all of that being said, adding coffee grounds to your compost is a great idea.

How Much Coffee Grounds Should You Add to a Pepper Plant?

Knowing how much coffee grounds to add to your pepper plants is very important and will vary.

As a general rule, when using coffee grounds as fertilizer, we advise that it be done sparingly. Too much may produce diminished and even negative returns. It’s best to gently mix a little bit in with the soil, because a little goes a long way.

If you are using coffee grounds in your compost, 10-20 percent coffee grounds is an ideal percentage of the total compost heap to aim for.

Can Coffee Grounds Hurt a Pepper Plant?

Now that we have gone over the many benefits of using coffee grounds in conjunction with your pepper plants, it is time to look at the possible negative side effects that they might have on your plants.

As mentioned earlier, coffee grounds contain acidity and are very high in nitrogen. Excessive acidity and nitrogen toxicity both have the potential to hurt or kill your pepper plant. For this reason, moderation is critical.

Another factor that must not be overlooked is the caffeine content of coffee grounds and caffeine’s effect on plants. The caffeine content will greatly differ depending on the type of coffee grounds used, their age, and other factors. Too much caffeine is capable of stunting your plant’s growth, and in some instances, can shock and kill it.

This is another reason why used grounds are highly preferred to new ones.

At What Stage of a Pepper Plant’s Growth Should Coffee Grounds Be Added?

Coffee grounds can be used to fertilize your pepper plant during any stage of its development but should ideally be added to the mixture at the initial stage, when growth is important. It is good to add coffee grounds from the onset of your pepper’s development because, as previously explained, the nitrogen in coffee grounds is not immediately available to the plant but only becomes available as the grounds break down over time.

This means that coffee grounds act as a slow, gradually released source of nitrogen for the plant.

If your pepper plant requires a fast-acting nitrogen source to recover it rapidly, coffee grounds are not suitable for the job, and a more readily available source will need to be used instead. If you are looking for a fast-acting and reliable plant nitrogen source, pick up Espoma UR4 Urea plant food.

Closing Thoughts

Coffee grounds are perfect for pepper plants due to their high nitrogen concentration. It is best when added at the early stages of growth.

Old, used coffee grounds should be used to avoid excessive caffeine and acidity, which can be harmful to your plants. In addition to fertilizer, coffee grounds can also be used as mulch, compost, or diluted with water and poured on the plants.

Here are Some of my Favorite Gardening Products and Tools

Thank you for reading this article. I hope you found it helpful for growing some new plants in your home or garden. Here are some products I like that I hope you’ll also find helpful. These are affiliate links, and I am compensated for referring traffic. But in all honesty, these are the exact product that I use or recommend to everyone.

Soil: For high-quality soil, I really like Fox Farm Ocean Forest. I do all my growing in containers and this soil has worked great for me. I like how they use nutrient-rich contents like earthworm castings, bat guano, and composted crab and fish.

Fertilizer: Currently I am using a seaweed-based organic fertilizer call Neptunes Harvest. This is a great milder fertilizer option if you want to use something organic. If you want a more powerful fertilizer, I recommend Fox Farm Liquid Nutrient Trio, lots of people have had great growing success with this product.

Pruning Shears: Pruning shears are one of the most useful gardening tools to have because it’s important to prune your plants to keep them healthy. The pruning shears I recommend are the Gonicc 8’’ pruning shears. I like them because they are built sturdy and work both on bigger and smaller plants, so you don’t need to have multiple pruning shears. is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to also participates in affiliate programs with other sites. is compensated for referring traffic and business to these companies.