It is a pretty well-known fact that if you want to grow a healthy organic garden, you’ve got to get away from using synthetic fertilizers on your plants.
This can be tough, particularly when you realize how expensive and hard-to-come-by organic fertilizers can be!
Fortunately, there’s one easy way to add nutrients to your garden – and that’s by using manure. Manure is a soil amendment that can not only improve the level of nutrients in your soil but can also improve its structure. This lends itself well to a garden that is well-draining, fertile, and easy to work with.
Unfortunately, not all kinds of animal manure are made alike. While some can be used with very few limitations, others should be used only with caution – if at all.
Here’s what you need to know when you’re trying to figure out which kinds of manure are best for your garden.
Why You Should Add Manure to the Garden
Manure is a garden amendment that has been around virtually since the beginning of time – or at least, since agriculture!
What is manure? It’s simply the waste of animals. Ideally, you will compost the manure first to give it time to break down the nutrients and to eliminate potentially harmful pathogens that can make you sick or damage your plants.
You can use uncomposted manure, of course, but you need to do so with caution. It will take longer to break down and could even contain weed seeds that can contaminate your garden. Not only that, but you may have realized that manure has a distinct odor – this isn’t necessarily something you want around your plants.
Raw manure can also make your plants grow thin and leggy, making it more difficult for them to establish strong roots. Therefore, if you add raw manure, you need to make sure you add it with plenty of time for it to break down. It needs to reach a temperature of 140° for a sustained period of time.
Manure can provide a whole host of nutrients to your garden, but the most well-known nutrient it can add is nitrogen. Many manures, such as cow manure, contain beneficial bacteria that can help convert nutrients into more easily accessible forms so that they can be accessed by your plants without burning their roots.
It can come from any animal, but manure from some animals are simply better than others.
Chicken Manure in the Garden
Chicken manure is one of the most beneficial types of manure you can add to the garden. It has high nitrogen content. Of course, all manures contain nitrogen, but chicken manure contains some of the highest amounts.
This also poses a slight disadvantage – you will have to compost it well to prevent it from burning your plants. You can apply it in the fall or spring, ideally after it’s had the opportunity to compost.
Avoid adding chicken manure to acid-loving plants and particularly to flowers. There is so much nitrogen in it that it can cause excessive foliage production at the expense of your flowers.
Pig Manure in the Garden
In the past, farmers used to till pig manure into the garden in the autumn. They would allow it to decompose, ready to be used to provide nutrients to the following spring’s crops.
While this works in theory, the one problem with pig manure is that it contains many pathogens that can also make humans sick, including E.coli, parasitic worms, and salmonella.
Fortunately, you can usually get by with adding pig manure to the garden as long as you compost it. Read our specific pig manure compost guide for this. Make sure you let it break down for several months to a year and be sure to turn it every four weeks or so.
Let it cook as long as possible, and then it’s totally fine to add. It doesn’t have quite as much nitrogen as chicken manure, either, so it may offer a more well-balanced blend of nutrients for your plants.
Sheep Manure in the Garden
Sheep manure can also be used in your garden. It has a lot of nitrogen, like the other manures, but since it is deposited in a pelletized form, it takes much less time to compost.
Sheep manure is a very slow-release fertilizer and is higher in phosphorus and potassium than many other types of manure. It is a low-odor fertilizer so many people use it to top-dress their garden beds. Again, composting it first is still the recommended method of applying it.
This kind of manure can not only help your plants establish strong roots but it can also contribute to the development of good organic matter in the soil. It can also be used as an organic mulch.
Cow Manure in the Garden
Cow manure has a high percentage of nitrogen as well, though not quite as much as some of the other manures. Its nutrients are held at a 3-2-1 ratio of nitrogen, phosphorus, and potassium. As with the other manures, you will want to give it plenty of time to break down.
Because cow manure is not quite as rich in nitrogen, it is a popular choice for gardeners. When composted, it can provide a lot of beneficial nutrients. Again, as with pig manure, you’ll have to be mindful of the potential pathogens that can spread to your soil if the manure is not composted first.
Cow manure consists primarily of digested grain and grass but can also transmit weed seeds to the garden. It also tends to contain more ammonia gas than other kinds of manures (with the exception of chicken manure), which is something to be mindful of.
Horse Manure in the Garden
Horse manure has a similar nutrient content as cow manure. However, it is extremely large and usually contains a lot of weed seeds. Therefore, you will want to give it a bit more time to compost and age (ideally more than six months – try not to just add it raw).
Horse manure is a great addition to any kind of crop, including a flower, vegetable, or root crop. If you’re adding it to a root crop, again, providing plenty of composting time is essential. Horse manure that is ready to be used in your garden will look a lot like fertile soil and will have lots of its strong manure smell.
Other Sources of Manure – and Ones You Should Avoid
There are plenty of other kinds of manure you can use to amend your garden and nourish your crops. Some other good choices include rabbit and goat manure. Goat manure is very similar to sheep manure and can be added in a similar fashion. When applying manure from other types of poultry, follow the same recommendations as you would for chicken manure.
Rabbit manure, interestingly, has about 4 times as many nutrients as cow or horse manure – it is twice as rich as chicken manure. Rabbit manure can help improve soil structure and often does not even need to be composted before it is used.
Avoid using manure from cats and dogs – along with manure from any kind of carnivore. These manures can harbor dangerous pathogens that can make you incredibly sick.
Where to Get Free or Cheap Manure
The best way to get free manure? Raise your own farm animals! Of course, I guess this isn’t a technically “free” method, since raising animals can be quite expensive. However, if you’re already raising animals, don’t scoop that poop and throw it out. Save it, put it in the compost, and use it on your plants.
You can also research local places near you that offer manure for sale. Often, local farmers will be willing to give it away. You can also buy bags of composted manure from your local home and garden store.
If you’re going to use manure in the garden, a good rule of thumb is always to compost it first. While there are some manure types that you might be able to get away with using fresh, if you’re having a hard time remembering which ones are safe, composting it first won’t ever hurt. It’s not just the high nutrient content you have to worry about.
Pesticides, herbicides, and other chemicals can stick around in the manure and make you sick or contaminate the soil, killing off helpful soil microbes.
One more word of caution – never use human manure. Not only can it pass drugs, diseases, and other pathogens to your soil, but it’s kind of gross, too, isn’t it?
Instead, use more common animal manures to fertilize your plants. They may not all be created equal, but fortunately, with a bit of know-how, you can add just about any type of manure (safely!) to your garden plants.