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Composted manure = multipurpose soil builder

The scoop on poop

Adding a layer of composted manure to your soil provides more than just nutrients to your soil. Composted manure is a great source of organic material which helps build good soil texture, retains moisture, and breaks up hard soils. Creating a habitat that promotes beneficial bacteria and microscopic animals is another benefit of organic matter.

Speaking of beneficial critters, composted manure is full of them. Healthy soil contains loads of microorganisms and their byproducts that can’t be duplicated by chemicals. As a matter of fact, chemicals can easily kill the necessary microorganisms and animals that live in your soil. A good rule of thumb is dead soil equals dead plants and soil full of living things grows lively plants.

We shall use no pooh before it's time

Well-composted manure is very different than fresh manure. Some gardeners prefer fresh manure because it has a higher nutrient content than composted manure. I prefer composted manure for several reasons. Tender plants can easily be burned by fresh manure. Fresh manure can compost in place raising the temperature of soil killing tender roots, whereas composted manure has already been through the composting process so it actually helps maintain optimum temperature for your plants by insulating them from high and low temperatures. Chemical fertilizers and fresh manure both have high levels of nutrients that can be released too quickly for plants to use and may do more damage than good. Composted manure releases its nutrients slowly so plants receive only what they need when they need it. As an extra benefit, the slow release of nutrients also means applications are needed less frequently. Fewer applications mean less work which is a huge plus in my book. And the most import reason to use composted instead of fresh manure is that composted manure is less likely to contaminate food crops. Fresh manure should be applied at least 120 days before any food crop is harvested whereas composted manure needs only 90 days.

Is it done yet?

How can you tell if your manure is composted enough to use? One way to tell is by smell. Fresh manure smells like manure, and nobody likes to hang out in a yard that smells like pooh. If it smells bad you sure as heck don’t want to spend a day shoveling it around your plants. Well-composted manure smells nothing like manure, but smells like rich soil. Even my dogs know the difference. I once applied a manure dressing that was not fully composted in my yard and had the unpleasant surprise of my dogs finding it irresistible. Every time I turned my back on the dogs they would either be eating it or rolling in it. No matter how much I worked it into the soil they just kept at it destroying everything in their path. I have been very careful about using only well-composted manure ever since and haven’t had that problem since.

Will any pooh do?

The answer to this question is a big no for any food crops. The rule of thumb on this is if the animal eats meat than you cannot use it. This includes dogs, cats, humans, pigs, and any other normally meat-eating animal. Even if the animal is fed a vegetarian diet you should not use it. The reason for this is an increase in the possibility of introducing pathogens to your garden. This still leaves plenty of possible sources of herbivore manure. The most common sources are cows, horses, and chickens but many more exotic kinds are available. Even zoos are jumping on the bandwagon and composting herbivore solid waste. Our zoo donates the composted waste to the local parks. Imagine the amount of compost an elephant can produce.

Another consideration is how the animal is raised. If an animal is pumped up with hormones and antibiotics it can be passed on to the manure. Antibiotics in the manure can kill off the microorganisms which can prevent the manure from composting fully. Another side effect of an excess of antibiotics is the promotion of antibiotic resistant diseases. I think we have all heard enough about the dangers of this, so I don’t think I need to convince you that it’s important to avoid. When it comes to hormones, I think it’s pretty obvious. Who wants to eat food that is growing in soil contaminated with hormones used to make beef cattle larger?

So what can you do to avoid antibiotics and hormones? If you are getting manure from one of your own animals then it is pretty easy, and you are probably already doing what is needed. The main thing is not to treat your animals with hormones and antibiotics unless it is medically necessary.

Do not overlook the animals’ feed when considering this. Mainly animal feeds are treated with herbicides that can be passed through the animals’ systems and end up in your compost which can kill the very plants that you want to grow. This can be avoided by making sure that the feed you give your animals is organic. As a benefit you will have healthier animals.

Unfortunately, if you are not raising the animals that are the source of your manure, you have no control over what the animal is fed and how often it has been treated with antibiotics or hormones. Research is the only thing you can do now. Fortunately due to the increase in the organic food industry this is becoming easier.

If you are in a part of the country where chickens are raised look for someone that is raising organic, free-range chickens. If you live in cattle country, look for a rancher that is raising organic, grass-fed cattle. I am fortunate enough to live in dairy country, and can purchase local organic dairy compost from garden centers. If you are having a hard time finding the perfect source of manure don’t give up on using composted manure completely. Keep in mind that even less than perfect composted manure still has more benefits than a chemical fertilizer.

(As an aside, the “organic” designation seems to mean less and less to farmers because of the high cost of obtaining that designation. Many farmers are effectively organic without the label, so it pays to know your source.)