Sunday, February 10, 2008

manure, compost, household waste

I've been thinking about comments by Patrick at Bifurcated Carrots and Linda Woodrow of my permaculture home garden Bible and reflecting on what exactly household waste for the garden is, or could be interpreted as.

Linda Woodrow talks about compost a lot. She talks about green compost, worms, chooks, manure, comfrey, seaweed. She encourages home gardeners to get their hands on lots of it and shows how to do it without buying any commercial garden preparations. She is a huge fan of the chook tractor method and suggests worms if you can't have chooks for any reason. She doesn't mention Bokashi but bokashi has been very useful for turning kitchen waste into garden food at our house. I suspect its popularity is fairly new in Australasia - probably newer than her book, or than the edition of her book owned by my local library. I have drawn on her instructions to make fertiliser brews out of horse poo, comfrey and sea kelp.

Patrick has written on his blog that he is unconvinced (if I can paraphrase him roughly) that manure and other fertilisers and soil conditioners are necessary or even appropriate for the home gardener, except for using home compost as a way of disposing of household waste. Patrick has a lot of intelligent and interesting things to say on his blog generally, and this idea has hung around me waiting for me to process it for some time.

So with regard to some processing, here is where I've got to:
I think the rub comes with an interpretation of what household waste is, or *should* be. If you are vegan, then it stands to reason that animal manure is not going to be part of your household waste. We are not vegan in our four person household. Our eating habits are enthusiastic of many types of animal and vegetable derived food. I have used the clearings of Rayleen's chook house (straw or bark mixed with chicken poo) on my compost and I'm delighted with the results. We've slaughtered and eaten three of Rayleen's unwanted roosters and bought and eaten eggs from her on occasion. Those remnants are in fact part of the household waste of our food. It's just that we are so used to being so divorced from the source of our food. Likewise, sheep manure (haven't got it yet but have a source in the form of Rayleen's sheep farming brother) is okay on our soil to me as we do eat sheep meat. I accept that we don't actually eat horse products, but still happy to collect horse poo from the small farms just a few kilometres from us. They want to get rid of it, so reusing on our garden seems to make sense. We live close to the beach and I'm happy with my ethic of removing a bag of plastic rubbish from the beach each time I collect a bag of kelp. Given the rubbish volume, I usually collect 2-3 bags of rubbish for every bag of kelp in practise.

I think that what I'm arguing is that if we take cognisance of a fuller range of processes and inputs which go into producing the food that we eat, then putting manure back into the ground of a home garden won't seem so artificial after all.

3 comments:

Anonymous said...

Think of it like vitamins.

Sometimes, if you don't get the proper vitamins in your food, you can get sick. Most people who eat a reasonably well balanced diet aren't lacking in any vitamins, but it can happen that you have a vitamin deficiency. If so, you can either improve your diet and include foods that have the vitamin you need or you can take vitamin pills.

Some people argue that you should never take vitamins, because you don't need them if you eat a healthy diet, and indeed if you don't have a healthy diet they aren't a proper alternative.

Other people take them every day, because they don't want to take a chance they are missing something. For most people, at the very least, this is a waste of money. Even though the risks are small, there are some risks taking vitamins you don't need. Some vitamins can be toxic if you get too much, and anytime something like that is manufactured there can be problems with contamination or other quality control problems. Most people can take vitamins for years without any problems. Most people who take vitamins have no idea if they are benefiting from them or not.

If you are taking a lot of vitamins, and you get sick, one of the first things you have to do is consider if it's a problem with the vitamins.

Really, most people don't need vitamins and I think most health professionals would suggest not taking them unless there is some reason to believe you could benefit in some way from them, because there are some actual or potential disadvantages to taking them.

Many people don't understand these same things apply to your garden.

I spent a considerable amount of time researching the reason why I didn't have a serious problem with garlic rust in my garden but many other people did. It seems likely the reason is having too much nitrogen makes the garlic rust worse.

Most of the people who had more serious problems with the rust had been adding large amounts of manure to their gardens, mostly only because they thought it was a good thing to do, not because they somehow knew they needed it.

Like taking vitamins, adding a lot of extra manure to your garden usually doesn't cause serious problems, but it can stress or kill almost any plant and it can make all your plants a bit less healthy. Most people simply don't need the extra nitrogen in their garden.

Most gardens have everything they need, and by minimizing inputs and outputs and doing proper rotations, it all just stays in your garden and gets recycled. Many people do this recycling with compost. As long as you are reasonable, it's not necessary to eliminate in- and outputs completely. Your garden is also a good way to recycle household waste or animal waste if you keep animals. The important thing here is to be reasonable about it.

Because manure contains a lot of soluble nitrogen, you have to be a little careful with it. Unless you know your garden needs nitrogen, because you have done a soil test or have some other clear reason to know, you probably don't want to add the manure directly to your garden unless you have either properly composed or aged the manure first.

Ageing manure usually means about 2 years, because this is how long it takes for the excess soluble nitrogen to dissipate. This is really a long time for most gardeners.

When you compost things you need a good mix of 'green' (nitrogen) and 'brown' (carbon). In this case, manure is 'green', because it is very high in nitrogen. Because it's so high in nitrogen, you need really a lot of 'brown' high carbon material like leaves or straw, more than most people have in their gardens. You need about 10% manure to about 90% straw or other material.

Once you have aged or composted the manure, it's more or less the same as compost made from plant materials. There's nothing special about it, that makes your plants grow any better in any way. There's nothing wrong with it, it's just not special in any way.

I personally don't find manure very useful, or like it very much, and this isn't connected in any way to the fact I'm vegetarian. I think manure smells bad, and isn't nice to work with. Waiting 2 years for it to age, or having to find enough straw or similar material to make a 10%/90% mix is too much trouble for me. I think this is probably true for most other people, and anyone who says they like using manure in their garden is probably using it too fresh and probably stressing their plants.

If and when I ever get chickens or other animals, I will probably put the manure into my garden. We have two indoor cats, and we have briefly looked into composting their poo, perhaps we will do this someday.

This all applies to adding anything else to your garden. Gardening 'by vitamins' is just not a good idea. Your garden doesn't need large amounts of anything added to it, unless you know for sure you have a very specific problem and are doing something to solve that problem. Your garden just doesn't need anything added to it just to make it healthy. In moderation, adding other things like seaweed or whatever won't hurt, but it's usually better to compost these things first. Unless you are solving some problem in your garden these things won't help make your garden healthier any more than taking a vitamin pill that you don't need.

Sandra said...

Ah. We are on different sides of a philosophical divide then Patrick. I am a vitamin taker and while aware that overuse of specific vitamins can be toxic and stupid, I've been fascinated to read more about vitamins and minerals and the role that reversing deficiencies (in NZ the classic deficiency is selenium, which shows through in our foods and bodies because NZ soil is deficicent in selenium) has in enhancing health.

If you get back here and do get a chance to read this reply, I would love to know if you've read Linda Woodrow's Permaculture Home Garden and if so, what you think of it.

Anonymous said...

Linda Woodrow seems to be an Australian author, and the book you mention for some reason is very expensive outside of Australia.

But no, I've never read it.