Vermicompost and manure are two great ways to repurpose waste and use an all-natural fertilizer. Both have benefits and limitations, so it is essential to understand the differences before deciding which is the right fit for you and your garden or yard.
Vermicompost is different from manure because it’s the byproduct of decomposition using various worm agents. On the other hand, manure is organic matter composed of animal feces, which may contain pathogens. While manure is a good soil amendment, it does not offer the same nutrients as vermicompost.
Although both vermicompost and manure have their uses in your garden, it is essential to understand their differences regarding your plant’s health and your own. Let’s run through the main differences between vermicomposting and manure, from production or purchase to which to use as fertilizer.
1. Vermicompost vs. Manure Physical Differences
Animal manure comprises feces from farm slurry or farmyard manure. While some manure contains plant material such as straw from animal beddings, slurry, on the other hand, does not contain bedding as the animals live on concrete slats.
The most common animal manure comes from:
- Horses
- Pigs
- Sheep
- Chickens
- Seabirds
- Bats.
Animal manure also contains other animal byproducts such as hair, blood, and bone.
Vermicompost uses several species of worms to decompose and recycle vegetable or food waste, bedding materials, and vermicast. Vermicast is the byproduct of organic matter, and worms then excrete the organic matter with higher nutrient levels and reduced contamination levels.
The most commonly used worms in vermicomposting include:
- Earthworms
- Red wigglers
- White worms.
2. Vermicompost Has a Higher Nutrient Content Than Manure
Vermicompost is high in nutrients because worms produce healthy nutrients and microbes when they process food. The nutrients in manure can vary greatly, depending on the type of animal, what the animal has been eating, the animal’s age, and many more factors. Often you have no precise way of knowing the nutrient content of your manure.
In general, chicken manure has the highest nutritional content of all animals. It has more nitrogen than vermicompost, but excess nitrogen can burn plants and damage their roots.
Here is a breakdown of the nutrients found in vermicompost created from food waste and several animal manures:
| Percent Nitrogen | Percent Phosphorus | Percent Potassium | |
| Vermicompost (Food Waste) | 1.3% | 2.7% | 9.2% |
| Chicken Manure | 1.8% | 2.7% | 1.5% |
| Cattle Manure (Dairy) | 0.5% | 0.2% | 0.4% |
| Horse Manure | 0.6% | 0.2% | 0.4% |
Another study found that vermicompost made from food waste contained higher carbon, magnesium, and iron percentages than pig manure.
3. Manure Contains Pathogens and Bacteria
Most common pathogens, and bacteria will die around 149°F (65°C). Vermicompost and manure do not reach this temperature, so they cannot kill these pathogens off.
These temperature constraints mean that both manure and vermicompost created with animal waste contain dangerous bacteria. In some cases, studies show manure from chickens has been found to contain salmonella, which dies at 113°F (55°C).
If you use animal waste too close to bodies of water, the pathogens can contaminate the water, which can be incredibly dangerous. In these areas, vermicompost is much safer.
Remember to use caution when handling any type of animal waste. This process includes wearing gloves, close-toed shoes, and washing your hands immediately after handling.
4. You Can Use Vermicompost on Consumable Plants
The pathogens and bacteria in manure have severe health risks and can cause serious problems if ingested. Similarly, plants grown in manure and vermicompost made from animal waste are unsafe for consumption.
However, vermicompost made from food waste is perfectly safe for food plants. Although worm castings are technically waste, worms do not produce the pathogens and bacteria in most animal waste.
5. Vermicompost Is Easier To Produce Yourself
You can make vermicompost from both kitchen and animal waste like cow dung. It does not take up much space, and you can even make it indoors.
Vermicompost bins require little maintenance. After setting it up, you will need to add a small amount of water occasionally, and you may need to add a bit more bedding every few months or so. Aside from that, you can leave the worms to go about their work.
Manure, on the other hand, requires a bit more work. Manure must be composted outdoors and needs much more room to dry out. Like vermicompost, you will need to water it occasionally to maintain 40-60% water levels.
You will also need to mix the manure compost every few weeks, turning it over to allow more air into the pile.
6. Vermicompost Is Ready Earlier Than Manure
If you were to add kitchen waste to a worm bin and collect manure from the field at the same time, the vermicompost would be ready to use months before the manure.
Manure itself must be composted. After collection, manure needs six to nine months to sit and dry before it is ready.
If you use it too early, it can burn the crops. Fresh manure also contains the seeds of weeds that the animal has eaten, which need time to become inactive to avoid inadvertently planting weeds in your garden.
Vermicompost, on the other hand, can be ready as early as three months, and that can be even sooner with a flow-through system. After you establish your system, you should be able to harvest fertilizer monthly.
The only downside to using vermicompost earlier is that it may not be as high in nutrients as castings that sit for a few weeks. Worm castings keep producing microbes even after the worms have processed them, so giving it a few weeks between production and use is beneficial.
7. Vermicompost Is More Affordable Than Manure
If you do not want to create vermicompost or manure yourself, there are plenty of places to get it, including local farms and most stores with gardening departments. For this article, we will discuss prices based on retailers. Your local farmers may be able to give you a better deal.
By weight, vermicompost is generally comparable in price or cheaper than manure. However, you will need less vermicompost than manure to cover the same area since worm castings contain more nutrients. In a small garden, there may not be too much of a price difference, but for larger areas, vermicompost will give you more for your money.
Now, if you keep animals and find yourself with access to free manure, that may be a more affordable option for you as long as you are not giving up too much valuable space to compost the manure.
8. Vermicompost Has Better Water Retention Than Manure
Vermicompost is light and has excellent aeration. These attributes allow it to hold more water than regular soil, which is especially important in hot climates where the soil tends to dry out quickly. Providing roots with easy access to water helps produce more robust and vibrant plants.
Manure does not hold water well, which is perfect for some plants. The one category that does not do as well in vermicompost is desert plants, who do better in soil that drains well. Desert plants can only tolerate vermicompost in small amounts, whereas they can thrive in manure.
9. Vermicompost Does Not Have a Strong Odor Like Manure
There is no getting around the unpleasant smell of manure. Although composting manure does take the edge off of the smell, it is still prominent.
Vermicompost has a natural, earthy smell similar to potting soil when you feed the worms appropriately.
If you are using your fertilizer on a home garden, your neighbors will appreciate the lack of odor.
10. It Is Easier To Control the Contents of Vermicompost
The contents of vermicompost are easier to manage because you have complete control over what you feed your worms. Most vermicompost bins use kitchen waste as the primary food source for the worms, while some use animal waste such as cat litter.
Although many of the microbes in worm castings directly result from the worms, their food source also determines the balance of nutrients.
With manure created by free-range animals, you cannot keep tight control over what the animals eat. For this reason, gardeners often prefer cow manure.
Cow manure is best processed because it travels through four stomach chambers, which have time to break down thoroughly. Conversely, horse manure is not preferred as a fertilizer because it often contains more straw.
Manure also includes seeds, both grass and weeds that are unwanted in a garden.
Conclusion
Vermicompost and manure are both great options for a fertilizer that also helps to protect the environment by repurposing waste.
Vermicompost is generally more versatile than manure and does not have the pungent odor that manure does.
The one area where manure is a clear winner is for desert plants, which do not thrive in vermicompost. If you have animals, creating your own manure compost can be a great way to save money.
