… and that other source of fertilizer…

The end product - composted human waste

The end product – composted human waste

Having written about urine as a source of nitrogen recently, I feel compelled to also mention that other sort of human waste that can be composted and used to enhance fertility. This seems to be increasingly referred to as ‘humanure’, but we’re really talking poo.

An aquatron composting toilet can be installed in a two-storey house

An Aquatron composting toilet can be installed in a two-storey house

When you live in an ordinary house on an ordinary street it’s fairly difficult to make use of this resource, although the Aquatron composting toilet can be fitted in an upstairs bathroom and there are other technical options such as the Separett range which require a fan to be run constantly, thus using electricity.  And so here, chez snail, this is one source of fertility that we don’t exploit. However, if you live in a different setting (as a number of my friends do) then you can collect and process humanure and use it to improve the fertility of your land. Many and varied are the compost loos that I have visited, but strangely I have very few pictures! The one thing they all seem to have in common is how civilised and un-smelly they are – often beautifully decorated.

Composting humanure at Karuna: it's initially collected in the dusbins before being transferred into the big bays behind

Composting humanure at Karuna: it’s initially collected in the dusbins before being transferred into the big bays behind

In some cases all waste is collected in a deep pit below the toilet structure and simply covered with a sprinkling of wood-shavings after each ‘deposit’, before it is eventually closed off, and allowed to compost for up to a couple of years. In others the waste is collected in a receptacle of some sort before being removed and composted away from the toilet itself. The latter is how the compost toilets work at Karuna, but in addition they ask users to separate urine (which is composted with straw) from solid waste (which goes into their large composting bins, tucked away behind the polytunnel). Interestingly, the process at Karuna seems to generate no smell and the end product is an appealing-looking compost that they have used extensively on site to enhance tree growth. So, whilst this is not an option open to everyone, it’s interesting to know that our waste need not go to waste.

Inspecting the end product at Karuna

Inspecting the end product at Karuna

Peeing in a bucket

I promise this is my last post about saving water for a while, but there are a couple of things I want to mention that have cropped up as a result of recent posts.

First, this week I decided that I would investigate a little more how much water we were using in the shower. It turns out that Mr Snail-of-happiness only spends about 3 minutes in the shower, whilst I spend about 5.5 minutes in there. Both times are much shorter than the average in the UK, which is 7.5 minutes. I also measured the water I used, so that I could find out the rate of flow of our shower. Our electric shower, it transpires, delivers about 4 l of water per minute; this is the target suggested by the Energy Saving Trust, so clearly we are not being excessive and I can stop considering changing the shower in order to reduce consumption.

Second, my friend Perkin from High Bank (a fabulous place to go for a holiday if you are looking for a cosy self-catering cottage close to wonderful places for foodies) tried to post a comment on my ‘more water-saving‘ post, but despite repeated attempts was unable to do so. What he tried to write was:

What about urine as a garden fertiliser, either neat on the compost heap or diluted on plants. It has the double benefit of massively saving toilet/flushing usage and of providing a free plant feed. Not the most socially acceptable of ideas, the fact that our compost heap faces a pub beer garden has caused surprise gasps 🙂

Well, we have a relatively private garden, but even so it’s fairly difficult for us girls to introduce urine directly onto the compost heap!

Urine is full of nitrogen and, because nitrogen is water-soluble, it’s one nutrient that gets washed out of the soil very easily. Many farmers (and gardeners) spend lots of money buying nitrogen fertilisers to apply to their land. Inorganic nitrogen fertilisers are produced by energy-demanding chemical reactions whilst all the time we flush away a natural source of nitrogen, treating this fantastic resource as a waste product.

A camping toilet, for discreet and civilised nitrogen collection.

A camping toilet, for discreet and civilised nitrogen collection.

So, Perkin is right – if we want free plant food and to save water, we should be using our pee in the garden. And the solution to collection? As the title of this post states – peeing in a bucket! OK, you may not like the idea, but it’s perfectly practical. Lots of camping and caravaning suppliers sell ‘camping toilets’, which are, essentially, a bucket with a toilet seat and a lid that seals well. Generally, the expectation is that these will be used with chemicals, but there is no need – a nice thick layer of wood shavings in the bottom will soak up the liquid and you can sprinkle more on as required. In fact, this is a great solution because the wood is carbon-rich and the urine is nitrogen rich, so you get a good balance of these two important elements to go on your compost heap. And, all that nitrogen acts as a great compost activator, so composting should happen nice and quickly.

So, don’t be squeamish – turn your waste into vegetables and save water, money and energy.

To dig or not to dig

I frequently hear about the value of using a no-dig system when growing vegetables, but a recent post by Deano on his Sustainable Smallholding blog has made me think quite a bit about this issue and about the entrenched ideas that can permeate specific approaches to gardening (or any other aspect of our lives).

If you have read much of this blog, you will know that I am interested in permaculture and using this approach for designing systems in my gardening and elsewhere. Often, in the permaculture world, one finds reference to no-dig systems. The idea is that, in nature, productive systems are able to establish and thrive without any turning of the soil like we use in traditional gardening and agriculture. In order to emulate natural systems, the principle is that organic matter applied to the surface of the soil becomes incorporated into the soil structure by the action of worms and other soil fauna; just like it would in a woodland.

Woodlands produce organic matter that is incorporated into the soil by the fauna

The theory is sound, but in practice it may not be the best option. Natural systems have no ‘agenda’ – the vegetation that develops on a soil is the one that can thrive there. When we garden, however, we have specific aims and a specific time frame: it’s no good having to wait for 30 years for a deep fertile soil to develop when we need to feed ourselves now. Usually the reason for digging is to loosen the soil and to incorporate organic matter. It is true that, in some soils, worms and other soil animals can do this quite quickly, but it is not the case for all soils, as Deano has demonstrated with his heavy clay soil. Clay is a valuable component of soils as it is mineral-rich, but it is also sticky, impedes drainage and dries rock hard, and when it is abundant in soil, it creates a difficult environment for worms. Its presence is to be valued but, like most things, in moderation. Other components of soil – sand, silt, organic matter, water and air – are also important. The addition of organic matter to a heavy clay soil can help to improve aeration, fertility (including the release of chemical elements from the clay) and drainage. Given enough time, worms will do the mixing for you, but if you need it to happen this year, then some mechanical incorporation is the answer.

One of the arguments against digging (or ploughing) is that it damages the soil structure and adversely affects the habitat of the soil fauna. This is, indeed, true. For example repeated ploughing can lead to the creation of a hard, impermeable ‘plough pan‘ at the depth that the plough reaches because it smears the soil at this level. In addition, digging or ploughing causes physical damage to soil fauna and flora – potentially killing worms and chopping up fungal mycelium, mixing up soil micro-organisms, exposing buried organisms to the surface and burying those from the top layers.

So, there are pros and cons… the essential issue is that you must know and understand your soil in order to select the right way to manage it. You must also understand what you need from your soil. It’s about making informed decisions. And this is, perhaps, the real issue: we should not allow sensible ideas to become dogma. There can never be a single solution that fits all situations, and by making rules and being prescriptive will inevitably lead to disillusionment when that answer doesn’t  work.

It’s not just humans who dig!

In fact, I don’t dig my vegetable beds much because, as I have mentioned before, there was very little soil in my garden when we moved in so we build raised beds. The imported soil was light and friable and supports large numbers of worms, which do mix organic matter in quite quickly. Having said that, however, I do dig. I particularly like in situ composting involving digging a hole and burying fresh organic matter – a mix of material high in nitrogen plus something like wood chip or shredded paper to provide carbon and improve structure – especially when I’m planting runner beans or members of the squash family. And sometimes I dig in compost for a quick addition and to stop the chickens chucking it around all over the place. Talking of which, the chickens do quite a lot of digging too!

But, perhaps I need to get to know my soil better in order to make more informed choices about how I manage it and, with this in mind, I’m going to be testing the pH of my beds soon and I will be thinking a bit more about the structure and texture of the soil.

Soil – getting to the root of things

Unless you are practicing an unconventional system of cultivation like hydroponics (see this great blog if you are interested in doing so) then soil is the foundation of everything you grow.

Gardeners tend to value their soil – they see what they are taking out in terms of crops and try to put something back – often by adding compost, soil improvers or fertilizers. My favourite addition to the soil is compost because it doesn’t cost me anything – I am converting what others would regard as waste (from the kitchen, garden or chickens) into a useful resource. I don’t tend to use commercial fertilizers or feeds, relying on compost, woody material from the willow hedge and other prunings, and worm wee. That’s not to say that I won’t use commercial fertilizers, I’m just too mean to buy them! I received a free gift of some organic liquid tomato feed earlier in the year and so I have recently been using this on potted crops – although it does make the greenhouse smell like someone has been storing fish in there for a week!

Unlike gardeners, many large-scale agricultural enterprises don’t use their ‘waste’ outputs as a resource, choosing instead to treat organic matter as rubbish and buy in fertility in the form of fertilisers derived from the petrochemical industry. In a recent post, Yambean highlighted the shocking waste when Spanish farmers dumped cucumbers in protest at being paid so little for them by the supermarkets. I asked her about this and commented that they would, surely, have been better composting them and returning them to the soil, but she tells me that composting is unheard of in that part of southern Spain and the soil is, as a result, completely impoverished. It’s shocking to me.

Soil is a complex system consisting of a mineral component, organic matter in various states of decomposition (from freshly fallen leaves and recently deceased animals to humus and root exudates) and living organisms (bacteria, fungi, worms, insects, other invertebrates, plant roots etc). It is common sense that we need to nurture such systems if we wish to make use of them. Unless we replenish the soil, it will not continue to be productive. This was the basis of the organic movement in the UK, you know? Ever wondered why the Soil Association (one of the regulators of organic produce here) is called the Soil Association? Well, it was founded in 1946, partly because of concerns about “the loss of soil through erosion and depletion”. In 1967, the association stated that “The use of, or abstinence from, any particular practice should be judged by its effect on the well-being of the micro-organic life of the soil, on which the health of the consumer ultimately depends.” So, you can see that their name really does reflect an acknowledgement of the key importance of the soil.

In large-scale systems, particularly where it is common to have periods when the soil has no vegetation cover, erosion is common. As the Soil Association noted in 1946, soil is not simply lost as a result of nutrients being extracted because we grow crops in it, erosion is also a problem. If you live beside the sea (as I do) you cannot help but notice the brown water around river mouths after heavy rain… this is the soil that was previously supporting plants. It does get replenished naturally – rocks weather and add to the mineral component, organisms die, excrete and shed parts of their bodies and add to the organic matter – but bare land is subject to high levels of erosion that can take a significant time to be replaced. Thus we lose substrate, nutrients and water-holding capacity because we chose to leave soil bare – a simple ‘green manure’ such as clover could reduce the erosion and enhance fertility (clover fixes nitrogen).

If we do not care for our soil is it any wonder that there is an increasing need to add to it from external sources and rely on non-renewable resources? Many people, when thinking of organic growing, focus on the absence of pesticides, herbicides and artificial fertiliser, but I’d like to suggest that one of the most important reasons to support organic production is because its practitioners care for the soil and are, thus, ensuring that it is available for future generations to use too. In my garden, I would like to think that I will leave the soil in a better condition than when I found it… not just preservation, but enhancement.

Where has all the soil gone?

When we moved into Chez Snail eleven and a half years ago I was very excited to have a blank canvas as far as the back garden was concerned. All that was there was an expanse of lawn and a patio – no trees, no shrubs, no bulbs, no flowers and no beds… and, as it turned out, no soil

Well, I say no soil, but that’s not entirely true: there was about six inches of clay above the shale that represents our bedrock. About a month after we moved in, our elderly dog died. We tried digging a hole in the back garden; it was December, it was raining and we managed to get down about a foot… we gave up. At this stage we were beginning to wonder what we could do – it was Christmas and the vets was closed, so cremation was not an option. Should we put the dead dog in the freezer for later disposal? Should we go and bury her ‘in the wild’? Should we build a mausoleum? After some debate we decided the try planting her in the front garden. So, shovel out, body discreetly just inside the house and we tried again. This time was more promising, there was a slightly greater depth of soil and then we hit concrete… some part of the sewage system we later learned. Then, inspiration. There was a healthy-looking hydrangea in a corner – perhaps its roots would have broken up the ground. And, indeed, success. The hydrangea was removed, the hole was expanded into a grave (fortunately the dog was quite a small terrier) and we could proceed. At which point one of our new neighbours came over to say hello. “Doing some gardening?” she enquired. “Yes,” we responded cheerily, heartily thankful that the body was still indoors and that we weren’t going to have to make small talk about deceased pets. The neighbour eventually disappeared back home (we were grateful for the rain at this stage) and the burial commenced, with her nose towards the rising sun and her favourite cuddly duck and a stone (she was inordinately fond of those) as grave goods. Hydrangeas are not my favourite shrubs, so we planted a lilac over our canine friend (I had one waiting to go in the garden somewhere) and planted the hydrangea in the hole with the concrete in the bottom. I’m pleased to report that both plants are doing well.

So, as you can tell, we are a bit short of soil here. We shouldn’t be. The field behind our house isn’t – but there’s a step of about 12 inches up to it. In this area, when they build houses, they strip the topsoil (and more) from the plot and sell it. This leads both to drainage problems and to a nightmare in terms of subsequent gardening. We have pretty poor soils round here to begin with, so losing the majority of what there was to start with just compounds the problem.

Because gardening to produce food was a particular intention, we had to take steps. We started by installing log rolls to create some beds in the lawn and mulching with black polythene to kill the grass. Once done, we added homemade compost and hoped this would allow us to be productive. Sadly the waterlogged ground in the winter caused the wood to rot and anyway the beds simply weren’t deep enough. So, we dismantled those after a couple of years, bought some old railway sleepers and created new beds – bigger and deeper. Unfortunately we couldn’t generate enough compost to fill them, so, with heavy hearts, we bought in some topsoil, hoping that it hadn’t come from some other building plot now bereft of a growing medium. And finally we had a sustainable system – raised beds don’t get waterlogged, we keep them fertile with compost produced on site (including willow shreddings and chicken poo) and we eat fresh food from them throughout the year.

I just can’t help feeling that much less energy would have been expended and the system would have been naturally sustainable if the builders had left the soil where it was in the first place! Grumble.

Finally... productivity

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