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Worm Composting With Manure

Guides to Making Worm Compost

“I have just started with worming composting. My question is: Is it beneficial to add some dehydrated cow manure to my mix of coffee grounds, egg shells (microwaved), newspapers (shredded), kitchen vegetable waste and cardboard? Thanks” ~ Steve V

Worm CompostingAll of the things mentioned above are great for the worm’s diet! Adding cow manure will definitely be a plus to your wormery system.

Cow manure is a great food source for worms. Not only cow manure, but hog, horse and sheep manure have all been proven to be great source of feed in vermiculture processes.

Manure is already partially decomposed which makes it easier for further breakdown by worms, yet it still contains a good amount of nutrition.

The Carbon and Nitrogen ratio in manure is also relatively balanced making it a very good product feeding worms and composting. This is why many farmers like to use manure for farming by leaving to one side and allowing it to sit there and age. Manure can start composting itself with relative ease by mixing it with bedding (carbon source) to give it more aeration and improve the composting process.

Worm farmers who are thinking of using fresh manure in their worm beds need to be aware that you will need to pre-compost it before you add any of it into your worm beds. The main reason is to get rid of any weed seeds that may still be in the manure. Weeds seeds have a protective layer which cover them, and starts to disintegrate as the manure ages and compost, where then micro-organisms can break the seed down and render it useless. The other reason for pre-composting is to lower the high nitrogen levels and inorganic salts which fresh manure may contain.

You are doing well by using dehydrated manure since they have already been treated either by aging or a heating process to dry out the manure, therefore you won’t need to worry about weed seeds as much. Most seeds should already be killed through the treatment process. Also, because you are mixing your dehydrated manure with other food stuff, you should not need to worry about moisture levels, vegetable waste should be able to provide a lot of the moisture a healthy wormery system needs.

Problems will arise if you feed it mostly or only dehydrated manure as it won’t provide enough moisture (which should be about 70-80%). Do check your own moisture levels, and if you find it is too dry; don’t be afraid to add some water.

We have already mentioned that cow / cattle manure is great for worms and composting, since we are on the subject of manure, I will talk about the qualities, advantages and disadvantages of other manures.

Pig / Hog manure – Excellent source of manure. A research done by the Ohio State University has found that the manure used created the best vermicompost out of all the other manure used. Again the manure will need to be pre-composted and de-watered if it is in the form of a slurry.

Sheep / Goat manure – Similar to cattle manure, great nutrition and easy to compost. May contain weed seeds and will need pre-composting before feeding to the wormery system.

Poultry Manure – Care is needed when using this source of manure. It is very high in nitrogen content which is why you won’t see farmers / gardeners use fresh untreated poultry manure to fertilize plants as it burns the roots. The high nitrogen content will also pose a problem with worms, therefore it needs to be pre-treated and given in small quantities to allow worms to adapt. Pre-treatment can include washing it down with water and pre-composting it with the latter being the best option. Mixing it with a carbon source such as newspaper will make it a better feed.

Rabbit Manure – This has been mentioned in previous newsletters. The manure from rabbits is good in nutrition but also contains relatively high nitrogen and salt content. Most of the time the manure is taken from the bedding of rabbit huts which will also contain urine, and is best to avoid throwing it into the wormery system. It can be pre-composted, but if fed in low amounts then adding a suitable amount of carbon will be sufficient.

Cat / Dog manure – There has been a lot of confusion with this, mainly due to retailers and instruction booklets of home composting systems giving out big warnings that pet wastes should not be composted. It is true that cat / dog manure can be more problematic, however if done correctly it is a perfectly good compostable product which worms can break down readily.

The problem with cat / dog manure is that the pet’s diet leads to wastes that may contain pathogenic organisms that may be particularly dangerous for pregnant women. Therefore it is not wise to use the vermicompost created on fruits and vegetable which you will consume, and especially NOT sell it on!

Because of this, it is best not to mix in your pet waste with the vegetable waste you are throwing in, as it ruins what could be great vermicompost for your vegetables! Instead create a separate wormery system to deal with this type of waste and make sure you add a lot of bedding. Using this vermicompost on trees, shrubs and other ornamental plants is fine.

You may have to deal with odors if using pet wastes. Adding bedding will help, but if you want to avoid any of this, digging your wormery underground can solve this problem. The good news is that when done properly, surprisingly it does not create much smell at all!

If pets are fed medication (especially worming medicine) this will transfer into the waste and kill the composting worms when they come into contact with it. So do make sure that no medication is being fed to your pets when using their waste.

Using pet waste will pose risks. So do keep children and pregnant women away from the waste. Cat faeces can carry a parasite that causes toxoplasmosis, which can affect fetal development.

Human Waste / Biosolids – Again this waste is perfectly compostable and worms will break it down readily. However it will pose risks and problems similar to pet feces and will need to be done separately and carefully to avoid odors and a pathogenic mess!

Vermitech is a great example of a commercial company which uses biosolids for vermicomposting. The company is a facility based in Australia, processing over 8,000 tonnes of biosolids using composting worms each year. However their system is well regulated and automated to minimize any risks which may be involved.

For home composting, this is recommended only to be used if you know what you are doing, and can use the waste in a controlled environment. There have been great examples of this done successfully such as the composting toilet by Joe Jenkins and other people.

Don’t be afraid to use all these great sources of manure as long as you do
it responsibly and carefully!

Allotment Growing UK has been granted exclusive & sole permission to republish the above article for the benefit of it’s visitors who are interested in composting with worms. Originally published in the excellent free worm composting newsletter – Worm Farming Secrets

If you would like further information, an excellent step-by-step “how to” guide, or have your own unique worm composting questions, be sure to visit Worm Farming Secrets now. With over 17,000 readers, Worm Farming Secrets is quite simply the leading worldwide authority on composting with worms. Click Here Now.

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