How Long Does Vermicompost Last?

Vermicompost is a great way to turn natural waste into usable, nutrient-rich fertilizer. But sometimes, worm casting production exceeds the current need. So how long does vermicompost last?

Vermicompost can last forever, although it is most effective within three years of production. The beneficial nutrients decline over time, reducing the effectiveness of vermicompost as fertilizer. When used as a compost tea, the efficacy of vermicompost is very short-lived.

This article will talk about the lifespan of vermicompost and the best ways to store it. It will also discuss the lifespan and storage of worm tea, a product you can make from vermicompost.

Does Vermicompost Expire?

Vermicompost does not expire because it is already wholly decomposed. However, vermicompost does lose nutrients over time, becoming less beneficial as a fertilizer. When stored properly, vermicompost can stay usable for three years or more.

Traditionally, expiration is thought of as decomposition. Worm castings are already decomposed. As long as they are stored properly, you can use vermicompost as a top dressing or mix it with soil indefinitely. 

However, like any other type of fertilizer, a few external factors can affect its effectiveness, such as animal interference and mold. Therefore, it is crucial to store vermicompost properly to maximize its effectiveness.

How Do You Store Vermicompost?

Vermicompost is typically stored in winter and can’t be used until planting in the spring. Or perhaps you are making more than you can use on your property. If you can’t find a use for it immediately, you will need to store it for later use.

You should store vermicompost in a container that is not air-tight and keep it damp. Proper storage of vermicompost determines how long it will last. The five-gallon buckets you can find at your local hardware stores make perfect containers. 

You can use whatever size container you like, but keep in mind the weight of your bin if you plan on moving it in the future.

To allow proper airflow, the container you use should not be air-tight. Drilling small holes in the lid or leaving the cover slightly ajar are good options to maintain circulation.

While you do not want your vermicompost to be too wet, it should never dry out completely. It needs some water to continue decomposing slowly, so keeping it slightly damp is best. Once vermicompost dries out and becomes hard, it will be impossible to restore it to its original texture.

The worms should be removed from your vermicompost before storage, although many vermicomposting bins will often separate the castings themselves. 

How Do You Make Vermicompost Last Longer?

You can make vermicompost last longer by storing it in an unsealed container. The key to making vermicompost last longer is proper storage. To preserve your vermicompost, you must control the heat, moisture, and interference of animals.

Control the Heat

Vermicompost becomes less potent very quickly at high temperatures. Controlling the temperature of the vermicompost allows the nutrients to last longer until you are ready to use it.

Fortunately, most vermicompost storage occurs during the winter, when people save their fertilizer to be used in the spring. 

The temperature of the vermicompost should not exceed 65 °F (18 °C), although it is best kept under 50 °F (10 °C). This often means that vermicompost expires more quickly in warmer climates.

One of the easiest ways to keep your vermicompost from overheating is keeping it away from direct sunlight. If you can find a shaded spot or keep it covered, that is perfect, but sometimes this will mean storing the vermicompost in a shed or garage. 

If you use your vermicompost to make worm tea, you must store it above freezing (over 32 °F / 0 °C).

Prevent Moisture Buildup

Excess moisture also contributes to the degradation of your vermicompost. It also leads to the growth of bacteria, fungus, and mold in your stash, which will make it unusable as fertilizer. 

To prevent moisture from building up in your storage container, you must have good air circulation. To achieve this circulation, you cannot store vermicompost in an air-tight container. Drilling holes in the lid of your storage container or not closing the lid all the way will help to prevent moisture build-up.

Airflow around the container is also necessary, and it helps if you can keep the bin from sitting directly on the ground. You can place it on a shelf or prop it up on a few bricks or wood scraps. 

Putting a layer of sand at the bottom of the bin will help to absorb any excess moisture.

If you used some of your vermicompost to make worm tea, you must let the remaining compost dry before putting it into a storage container. Spreading it out in a thin layer is the fastest way to take your vermicompost from soaking to damp.

Keep Away Unwanted Animals

If animals get into your vermicompost stash, it can be a big problem, and once they infiltrate the bin, it is almost impossible to get rid of them. The biggest threat to your vermicompost pile are insects such as ants and flies, which can steal the nutrients in the stash.

Whether you keep the lid slightly ajar or drill holes in it, adding a layer of mesh or screen will keep insects out without sacrificing airflow. Adding wood chips to the top of the pile will also help deter unwanted pests.

How Long Does Worm Tea Last?

Aerobic compost worm tea lasts 24 hours at room temperature and three days in the refrigerator. Anaerobic compost tea can last longer at temperatures above freezing. Worm tea loses nutrients quickly, so it is strongest immediately after it is made. 

Worm tea, a compost tea made with vermicompost, is created by steeping worm castings in water to create a concentrated, high-nutrient liquid fertilizer. It is always best to use worm tea immediately after it is made. But if you need to store it for a bit, you must keep it above freezing, or it will separate.

There are two different types of worm tea, aerobic and anaerobic, which have slightly different properties and storage requirements.

Aerobic Worm Tea

Aerobic worm tea is made with an air pump and uses sugar to ferment. The created microbes need oxygen to live, so it does not last long after it is made.

Aerobic worm tea needs to be used within 24 hours at room temperature (68 – 77 °F / 20 – 25 °C) to receive the full benefits. After 48 hours, the worm tea will no longer have any nutrients. While storing the tea, you need to stir it regularly to keep it oxygenated. 

Worm tea should also be stored in a container without a lid so that its oxygen supply is not cut off. 

Worm tea is usually made in large batches, so it isn’t easy to fit in a refrigerator. However, if you need the tea to last longer, you can store it in the fridge for three days with the lid off the container to allow air circulation. Remember that vermicompost is worm castings or waste, so you need to store it separately from any food products to prevent the spread of bacteria.

Anaerobic Worm Tea

Unlike its aerobic counterpart, the nutrients in anaerobic worm tea do not need oxygen to survive. This gives it a longer shelf life, although there is no agreed-upon maximum length of time. 

Keep in mind that the longer shelf life of anaerobic worm tea is because it initially has fewer microbes and nutrients. So, there is a tradeoff between shelf life and nutritional benefits to consider.


Vermicompost can last forever and provide suitable nutrients for over three years when handled and stored correctly.

The most significant factors that will determine the quality and longevity of your vermicompost bin are heat, moisture, and animal interference. Managing these threats will make your castings last longer.

On the other hand, worm tea does not store well and is best used immediately after it is made. It begins losing nutrients very quickly, is significantly depleted in 24 hours, and loses all its benefits after 48 hours. 

Alexander Picot

Alexander Picot is the principal creator of, 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.

Recent Posts