Does Lawn Fertilizer Go Bad? (How Long Does it Last)

It’s been a while since you last fertilized your lawn. You visit your storage shed and realize several bags of fertilizer were stored a couple of years ago. Now you are wondering, does lawn fertilizer go bad?

Granular fertilizers will last for many years or indefinitely if stored in a cool, dry place. On the other hand, Liquid fertilizer in unopened packaging can last somewhere between 4 to 10 years.

Shell life is one of the main differences between liquid and granular fertilizers. These two also differ in their mode of application, how long they take to work, and their costs.

Does Fertilizer Go Bad?

It depends on the form of fertilizer, that is, granular or liquid. Most granular lawn fertilizers contain a combination of three active ingredients, namely: nitrogen, phosphorus, and potassium. Others also contain calcium, iron, copper, or magnesium.

These minerals stay active, and their composition does not change or degrade over a long period of time. However, it is different for liquid or organic fertilizers. Their shelf life may not be longer as compared to dry granular fertilizer.

Granular fertilizers never go bad, you can unwrap a bag that has stayed in the store for years and apply it on your lawn, and it works. The granules inside the bag may clump together when stored for longer, but this does not lower its effectiveness.

You simply break up the materials and apply them on your lawn. High humidity is the reason why dry granular fertilizers may cluster together. It is important to store it in a cool, dry place free from moisture.

On the other hand, liquid fertilizers can go bad. All liquid fertilizers have an expiry date on their packaging. They contain additives that decrease their shelf life. Before spraying it on your lawn, check the expiry dates to ascertain if it is safe.

Liquid fertilizers made from organic materials tend to break down quicker than their synthetic chemical counterparts. They may also settle over time. Shake the bottle well before using it. If not careful, you may apply the liquid on the top and leave the real fertilizer settled at the base of the bottle.

Signs that a Liquid Fertilizer has gone bad

There is some tale tell signs that may show a liquid fertilizer has gone bad. They include:

1. Bulging Bottle

If you store liquid fertilizer for reuse but realize the bottle is bulging after several months or years, it’s an indication that it has gone bad.

Once the bottle is opened, it is difficult to control how long the active ingredients will remain dormant. Molds will literally start feeding on the components while releasing gases that cause the bottle to bulge.

2. Change of color

A change of color indicates that the liquid fertilizer has gone bad. For instance, if the content is colorless, it may change color to light green or yellowish. It simply means that the active ingredients are undergoing a chemical change.

3. Mold growth

When you open the bottle and look inside, you can visibly see mold growth. A bulging bottle characterizes it due to the gases released by the molds. Mold growth also results in discoloration and the fuzzy appearance of the fertilizer.

4. Odd smell

An odd smell is always an indication that something is not okay. The liquid will take a strange consistency and a bad odor. If liquid fertilizer exhibits this indication, do not apply it on your lawn. It may have some negative effects.

How long does fertilizer last in the soil?

Fertilizers can last in the soil anywhere from a week to several months. The exact amount of time is determined by the fertilizer you use.

If the fertilizer is granular or liquid

Granular fertilizer is in the form of dry granules. It is applied into planting holes before planting or can be applied at the base of an already growing plant. It breaks down gradually to release nutrients into the soil.

While liquid fertilizer is applied directly to the plant. It is absorbed through the leaves and used by the plant immediately. It can be applied to the plant after planting or at any stage of the growing season.

Both liquid and granular fertilizers contain the same nutrients needed by the plant. However, their distinct difference is how each last in the soil. Granular fertilizers tend to last longer in the soil than liquid fertilizers.

Whether the fertilizer is organic or chemical

Organic fertilizers are environmentally friendly; they don’t contain synthetic chemicals. They contain bacteria and other microorganisms that improve the soil’s overall health.

Like other synthetic chemical fertilizers, organic fertilizer contains nitrogen, phosphorus, potassium, and other nutrients needed by the plant.

Organic fertilizers are most beneficial to your plants. Although they take a longer time to decompose before releasing nutrients. They can last in the soil for several years.

Also read: How long does it take granular fertilizer to work?

How to store lawn fertilizer for longer

The shelf life of your lawn fertilizer depends on how you store it. The fertilizer will go bad easily if mixed with pesticides or when in contact with moisture. The following tips help to maximize the shelf life of fertilizer as well as prevent it from clustering:

1. Store lawn fertilizer in a cool, dry place

When intending to store your fertilizer for a longer period of time, ensure it is stored in an area that is free from moisture. Store it above the ground in a wooden cabinet. It can absorb moisture when placed directly on a cold floor.

2. Keep the fertilizer in its original packaging

 The original packaging is designed to dry the fertilizer and prevent contamination. Changing the packaging can expose the fertilizer to moisture, sunlight, or other agents that can lower its shelf life.

3. Ensure the bags or packaging containers are closed off tightly

Air-tight packaging reduces the chances of the fertilizer coming in contact with moisture. The fertilizer also remains in its original state when the bag is tightly closed.

4. Ensure the liquid fertilizer won’t become frozen

Liquid fertilizers are likely to freeze, especially during a cold winter season. Keep the environment around the fertilizer at room temperature. The temperature should be optimal; too low temperatures can damage the fertilizer.

5. Keep the fertilizer away from pets, rodents, and other animals

If you have pets or other animals, ensure that you are storing your fertilizer in an area they can’t access. You do not want to find your pets poised by the fertilizer. Rodents are usually notorious for creating holes in the packaging bags.

6. Store your fertilizer in a protective coating

It can be challenging to maintain optimum temperature and humidity in your store. That is where the protective coating comes in. They help to prevent fertilizer from dust, clustering, and absorbing moisture. This enhances the viscosity of the fertilizer.

7. Store away from other chemicals

Keep the fertilizer away from combustible materials or other chemicals. The fertilizer may degrade in the process of reacting with other chemicals. Store in an area that is well-ventilated and away from direct sunlight.

Final Thought

Dry granular fertilizer can last indefinitely as long as it is stored in a good place away from high humidity. The fertilizer may cluster together, but it will still be effective and safe to use on your lawn or plants. Liquid fertilizer has an expiry date usually indicated on the packaging. Expired fertilizers are harmful to plants.

Leave a Comment