Why Does My Fertilizer Smell Like Ammonia?

Sometimes, gardening is more intricate work than one would think. There are many components to consider, and sometimes, unpleasant smells may arise from your garden after applying fertilizer to your soil. 

Fertilizer begins to smell like ammonia when there is a lack of oxygen present. The smell of ammonia is especially common in organic fertilizer options such as compost. Gardeners should avoid applying fertilizer to their plants if there is an unpleasant smell present. 

Continue reading this article to learn more about why fertilizer smells like ammonia. Additionally, I will discuss essential steps gardeners can take to help sterilize and process their fertilizer when an odor is present. 

What Is Ammonia, and What Does It Smell Like?

When gardening, it is normal to experience a wide variety of odors and smells. Sometimes, these odors are benign and expected, while other times, they are not. One odor that is not normal is ammonia. 

Ammonia is a gas that helps release nitrogen in fertilizer, and it smells like urine, sweat, and/or body odor. Ammonia is especially notable in organic fertilizers but can also exist in synthetic blends. Fertilizers that smell like ammonia may need proper balancing or sterilizing. 

Ammonia is composed of nitrogen and hydrogen and interacts with its environment in many ways. It can be challenging to know when ammonia is present, especially if you are not familiar with the smell. 

However, nitrogen is primarily reliant on ammonia for proper distribution, and ammonia is present in many, if not all, fertilizers. If you notice an unpleasant smell in your fertilizer, it’s essential to take the following actions:

  • Halt giving your plants fertilizer and possibly replace your fertilizer. Plants should not receive a fertilizer that lacks oxygen or balanced nutrients. This can, unfortunately, cause more damage than good to your plants. 
  • Sterilize your fertilizer. Although it is recommended to avoid giving your plants unbalanced fertilizer, giving your plants the fertilizer that smells is an option to consider for organic blends like manure. Soil can help neutralize and save ammonia-ridden fertilizer if the smell is caught in time, and it can also supply your plants with some nutrients. 
  • Switch your urea fertilizer formulas. Many common urea fertilizers are high in nitrogen and contain ammonia. If you smell ammonia, it is best to avoid spraying and consider switching to a different type of urea blend.
  • Test your soil or speak with an expert. The pH levels in the soil are essential, especially when fertilizing. Ammonia can become affected by pH levels in its surroundings. This can interact with the smell that you may be experiencing. Soil with low to average pH levels can help neutralize the ammonia. 

Can Soil Smell Like Ammonia?

Gardeners worldwide have come to love the art of caring for their plants. However, there are many components that come along with gardening. Some of those components are unknown, while some are known, and one of those components is rotting soil. 

Soil will smell of ammonia when there is a lack of oxygen present or lack of drainage capacity. The smell of ammonia is not as common in soil, but it can happen. The smell of ammonia will occur, most times, when the soil is compact. 

Soil provides a structure for plants to thrive. Without a proper structure, plants can suffocate, and there may be certain rotten smells that are present. 

Ammonia usually shows up in soil when there is a lack of oxygen or if there is no available room in the soil for water to drain. However, it is not as common as one would think. 

Luckily, if your soil smells like ammonia, there are a few helpful things you can look for in your soil before helping it mend: 

  • Put a stick or a hanger in your soil to see if it is compact. You can also use your hands, but a coat hanger or metal type of stick will help preserve the soil’s structure and organic compounds. If you cannot stick something into the soil easily, it may be compact. 
  • Notice how much moisture is in your soil. Moisture is great for soil but can be a problem if there is no room for drainage. Sometimes, compact soil or soil that has no room for drainage can become very wet and can be hard to work with. 
  • Evaluate the smell. Some parts of your soil may smell clean and odorless, while others may smell rotten. The rotten soil may be where gardeners need to focus their attention. 

Mending Rotten Soil 

Rotten soil is never fun for anyone. It can leak an unpleasant smell and be frustrating to deal with as a gardener. Luckily, there is an easy solution for fixing soil that is rotten. 

The main reason why soil is rotting is because there is no airflow. Without oxygen and space for the plant’s root system to process nutrients, your garden may turn into an unfortunate disaster. 

To mend soil, gardeners must drain the soil and de-compact their soil without ruining their plants. Many gardeners know how to water down plants after fertilizer burns, but helping soil breathe is a completely different concept. Here are a few helpful tips. 

  • Avoid breaking up soil and exposing living bacteria to the air. The easiest way to break up soil might not appear to be what many think. Tearing up soil and moving it around with your hands is not a positive way to deal with compact soil. This method can entirely destroy the root system of a plant and the living components in the soil. 
  • Consider using an alternative method to break up the soil. There are effective methods for breaking up compact soil to give airflow. Individuals can use a digging fork, a spade, or a trowel to create airflow. Another solution is to use compost. It’s important to remain gentle through this process. 
  • Halt watering your plants until the soil has drained. If water is not draining and your soil is compact, your plants may be suffocating. It’s important to halt giving your plants water until the soil has been mended. 
  • Give drainage holes to your plant if potted. Drainage holes can make a huge difference for potted plants. It can help the process move quickly, especially once the soil has been loosened. The water will begin to drain, and your plants will begin to thrive again. 

Can I Use Core Aeration To Mend My Garden’s Compact Soil?

The plant world has been around for a long time, and there are many experts that have created fantastic solutions for mending compact soil of all kinds. Unfortunately, some methods work better than others for certain circumstances. 

Individuals can use core aeration to mend their lawn but should not use this process in a garden. At the very most, individuals can poke holes with a planting fork in the ground to allow airflow into the soil. Core aeration is designed for lawns. 

Core aeration is an extremely helpful process for lawns. Individuals are able to create holes in the ground to create airflow, mending compact soil. Most times, this is accomplished with a large machine that runs across a lawn. Gardens, however, are much more delicate and cannot withstand this process. 

There are other solutions that individuals can use for gardens. The most popular way of mending rotten soil in a garden is to use compost. Gardeners can place compost on top of their compact soil. This can provide many benefits. 

  • Nutrients will begin to blend into the compact soil. Compact soil can benefit from the hydration of compost and will begin to absorb nutrients and strength. This can help loosen up soil a bit. 
  • Earthworms will begin to blend into the compact soil. Earthworms and other organisms will crawl into the soil, which will help move it around and loosen it. Compost is recommended because of this main reason. 
  • The tight soil will begin to loosen up. Compact soil is usually stuck in one place, but the many elements of compost will change the composition of your current soil. This can help with oxygen and moisture flow. 
  • The tight soil will increase its water-holding ability. Compact soil usually has a challenging time holding water because it is so tight. However, compost can enhance your soil’s ability to hold water by giving it nutrients, strength, and movement. 

Another option, as mentioned, is to produce small holes with a digging fork or a spade. Gardeners, if uncertain, can also head over to their local garden store to speak with an expert and potentially have their soil tested for more information. 

In Conclusion 

Ammonia is necessary for fertilizers and, sometimes, it shows up for gardeners in smelly ways. 

However, when ammonia starts to smell unpleasant, that’s when gardeners know that something has gone wrong. Luckily, the right tools and knowledge can make everything easier. 

If you can, check your soil often and store your fertilizer properly. This can make a huge and influential impact on your plants, your soil, and your gardening experience in the long term.

Be sure to check out my other article about how long an open bag of fertilizer lasts: How Long Does an Open Bag of Fertilizer Last?

Alexander Picot

Alexander Picot is the principal creator of TheGrowingLeaf.com, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

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