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Compost and how to make it
If compost making were as easy as the books tell us then why would we spent so many words discussing it? MGS members have been puzzling over it for years and here are some of their thoughts. We start with the basics from the MGS leaflet which covers compost. Then on to how one of the Garden Assistants at the MGS garden at Sparoza, Piers Goldson, adapted to the Sally Razelou method. Finally, the members give their own take on the “vexed question” – how to make compost in a mediterranean climate.
Gardening in a Mediterranean climate: Mulches and compost
MGS Leaflet (part)
Compost making at Sparoza
By Piers Goldson TMG no. 39 January 2005. Piers was the compost king at Sparoza, but we have to remember that he was the full-time gardener; part-time and absentee gardeners have a harder time of it.
Answers to Piers‘ question about pine needles
TMG no, 40 April 2005
Common stag beetle, Lucanus cervus, and a pile of oak leaves – a recipe for great compost
by Graham Petty from ‘Ask the Expert’. Graham describes a novel way to get a compost heap to ‘work’; having found that the beetle larvae in his heap were helping the decomposing process, he recycles them every time the heap is cleared.
Letters to the Editor on composting
TMG 3 & 5, 1995 & 1996
Right back when the MGS was in its earliest stages the problems with composting were being discussed. The soon-to-be President, Heidi Gildemeister, gives her opinion also.
Composting in a mediterranean climate
A discussion abridged from The MGS Forum
Elsewhere on the website
Visit to the Mygreencycle green waste recycling plant, Cyprus Branch March 2011
A visit to Renee and Ron Fitch’s garden, Xerosterni, Apokoronas, Crete Branch April 2014
From the MGS leaflet: Gardening in a Mediterranean climate: Mulches and compost
What is compost?
Compost is a natural organic fertiliser which adds nutrients to the soil and improves soil structure. It is the product of the natural recycling, through decomposition, of organic waste from the kitchen and garden.
What can I make it from?
Dry leaves and grasses, withered flowers, annual weeds, finely chopped or shredded prunings from the garden (and grass cuttings from the lawn mower if you have a lawn), as well as fruit and vegetable peel of all kinds, coffee grounds and tea leaves from the kitchen and wood ash from the fireplace. Paper and cardboard can also be composted; in the mediterranean climate it is best to shred and moisten these before adding them. ‘Brown material’ – i.e. shredded prunings – and ‘green material’ – i.e. vegetable peel or lawn cuttings – need to be evenly mixed.
What should I not put on the compost pile?
Cooked food containing meat, fats or oil; the excrement of dogs and cats.
Can compost be made in a hot, dry climate?
Yes, although you will need to remember to keep it moist during the summer. It is a good idea to cover your compost (with, for example, a tarpaulin, a thick layer of damp newspaper or a bit of old carpet) to conserve moisture in summer and to prevent it from becoming waterlogged in winter.
Where do I make compost?
Compost can be made in well-drained pits about one metre deep, in boxes at least one metre square made of wooden slats or boards, or in one of the many types of compost bin available on the market. You may also use four wooden posts and chicken wire to make your compost container. In all cases, the front should be easily removable, both to facilitate regular turning of the compost and to enable you
to take it out when it is ready. Do not make your compost on a concrete slab: not only does this prevent good drainage but it also prevents access by beneficial earthworms and soil micro-organisms. Whereas in temperate climates compost containers usually ensure good aeration by having air holes or spaces between the slats, in the mediterranean climate these tend to cause the outer layers of the compost to dry out too much. In hot, dry climates it is a good idea to line the sides of the compost container with cardboard from old cartons or thick layers of newspaper as you build up the material: this helps to retain moisture and the internal heat necessary for decomposition. It is a good idea to have at least two pits or bins, so that you are adding material to the second while the first is in the process of decomposing into a rich, crumbly, brown, odour-free ‘soil’.
Flies and grubs
To avoid attracting flies, it is a good idea when you add kitchen waste to the compost to cover it at once with a layer of shredded prunings or garden weeds.
In the Mediterranean, the larvae of the rose chafer beetle are often found in compost (large, fat, unattractive pinkish-white grubs). These are not generally harmful to the garden but you should avoid introducing them to the soil of plants grown in pots, whose roots they may damage.
To decompose properly, compost needs:
- Oxygen: The maturing compost must be aerated by regular turning, about once a month, with e.g. a pitchfork. Some commercially available compost bins are set on an axis and can be ‘tumbled’ to aerate them.
- Water: in hot dry summers the compost needs to be kept moist (though not sodden). If you make your compost in a pit, you must make sure that it is well drained.
- itrogen: nitrogen is present in the plant material being composted. However, a little rotted manure can be added to start the decomposition process. Urine is also a good source of nitrogen (easier for male gardeners to supply than for females).
- Compost accelerators may also be used: for example the leaves of seaweed, nettle, dandelion, borage or comfrey, or the liquid produced by soaking these leaves for two weeks in a bucket of water. Commercial compost accelerators are available.
How long will it take?
About three months if there is a good mix of materials, turned once a month and kept moist (not too dry and not too soggy). With a correct balance of material but with no turning it will take from six months to a year. With a poor mix of materials and no intervention it will take longer. The more finely shredded the material is and the better mixed, the faster its decomposition.
How do I use it?
Compost can be dug into the soil before planting. It can also be mixed with garden soil to form a potting medium.
Compost making at Sparoza
By Piers Goldson TMG no. 39 January 2005
When I arrived at Sparoza in September 2004 there had been plenty of pruning of dead and damaged plants, the heavy snows and cold of the preceding unusually cold winter having caused much damage. The pruned material lay in vast piles and my first job for my first week was to send it all through a small hole of a shredder. I survived the first week and will soon be reaping the benefits in the nursery. In the gardens of Sparoza there is a three-compartment system of compost bins – or perhaps I should call them holes, because they are below soil level – with a depth of about 3 feet. All the pruned material was shredded into the holes and mixed up with the South African succulent Mesembryanthemum cordifolium (syn. Aptenia cordifolia), a plant that grows very well through the summer and winter at Sparoza (it survives around -8°C). This was added as it is a great source of nitrogen which acts as a catalyst for composting. Incidentally, if you are short of a catalyst then common gardener’s urine works just as well; I added plenty of the latter and the temperature of the compost rapidly exceeded 57°C and indeed at times was barely touchable. (I also worked out that every time I aided the compost in this manner I saved 5 litres of water from flushing.)This type of subterranean compost bin requires more turning to keep it aerated – I generally do this when the temperature of the compost starts to drop. A consistently low temperature may mean that the compost is too dry, although compost that is ready also ceases to be hot: the gardener must use his or her own judgment as to which of these is the case. As an indication, compost that is ready is of a good, rich, dark colour and even texture (except for woody pieces which have not yet broken down – see below): all identifiable leaves and soft material will have been ‘digested’ and decomposed. At Sparoza, after less than two months of adding kitchen waste, including lots of coffee grounds, the compost will soon be ready for the nursery. It will be sieved to remove any un-composted wood which saps nitrogen from the soil and plants. This can be sent back to the bins for more composting. From the nursery the compost will go either into the garden around the roots of plants or off on its travels after the next MGS plant exchange. I only hope the volunteers will return to help us at Sparoza now that they know the wonderful soil in the nursery may still contain the remains of common gardener’s pee!
Compost, like most living things, needs irrigating and I am happy to know when I do my laundry in the gardener’s room that the phosphate-filled water from the washing machine goes directly to the compost bins. The advantage of the subterranean compost bins is that they hold their moisture well and require less water than compost heaps above ground, especially in a spectacularly dry area like Attica (although drainage in the bottom of the pit is very important). By contrast, the unshredded compost that was in the conventional above-ground bins near the nursery hadn’t really composted much at all, giving very little decomposed matter after many years. I was even able to identify in it many of the winter and spring annuals of 2003-2004, still nicely dried and preserved (some Cerinthe retorta still had colour in the flowers). This material has now all been shredded, reducing the size of the heap considerably, and with more frequent additions of water than the subterranean bins it is now also attaining temperatures of above 57°C.
I have a question: does anyone know quite what to do with pine needles? They just seem to sit there! And has anyone found a use for them in any other way in the garden.
Answers to the question about pine needles
Letters to the Editor TMG no. 40 April 2005
I have an answer to Piers Goldson’s query in TMG 39 about what to do with pine needles. As these needles are acid, I use them as a mulch around my strawberries, instead of straw. Not many books tell you that strawberries grow better on acid soil, but it is true and if they can be encouraged this way, why not?
About ten years ago my husband and I decided that we were getting rather old for the stooping down and gathering of our strawberries, so we hired a man with a digger who made four troughs from our existing terraces and lined them with bricks. Before we filled each trough with earth we filled the bases with all the pine needles we could gather in order to acidify the alkaline soil with which we then filled the troughs. How long it has taken to rot down the needles I do not know as these troughs are at least three foot six inches high, but I do know that we have had marvellous crops of strawberries ever since!
I read Piers Goldson’s article about compost (TMG 39) and learned a lot. In his last sentence he asks what one could do with pine needles. We have a house in Southern France near Toulon. Our neighbour has often asked us for pine needles. He lays them around his strawberry plants to keep them moist; strawberry plants apparently like acid soil. I hope Piers grows strawberries or has a neighbour who does.
A. B. H.
I write in answer to Piers Goldson’s question in his article on “Compost-Making at Sparoza” (TMG 39) about what to do with pine needles.
Some years ago I read in a German gardening magazine that when you compost the needles below a large pine tree the soil beneath it becomes rich, with an acidic pH value. Over the years, plenty of pine needles accumulated in my garden from a Pinus pinea and two other large forest pines. After the winter rains there was always a lot of vegetation here, yet as spring advanced it died down. The situation changed drastically when ivy took over the area. For some time I did not pay much attention to what was happening; later, however, I noticed that the pine needles had begun to compost under the ivy. The red earth here became black and friable. The magazine’s theory was borne out, since today in this area, densely shaded by many pines, camellias and hydrangeas and three grevilleas grow well and flower profusely. There are now few mineral deposits.
I should add that I use all material from the shredder directly as mulch, and I put anything and everything through the shredder. Today there is no part of the garden that is not green.
I allow the ivy to grow wherever it wants, with the result that it has covered practically all the spare ground. This “green valley” is very impressive during the hottest part of summer, for it is always fresh and green. The disadvantage of ivy, as we know, is that it likes to climb up trees and eventually kills them. Thus it is wise in autumn to cut any ivy branches that have started climbing; if you do this they will die, even if they are high above your head, and the wind and wet of winter will remove any traces of ivy from the bark.
I know that the particular site of our garden and its large size help me to work with nature. Nonetheless, I think my trial and error tactic with ivy and pine needles was worth the trouble.
I garden just outside Rome and have two umbrella pines in the garden. I have used the needles to mulch fruit trees with great success. But the thing that really surprised me is that after two years, when the needles had rotted down, I found high quality grass growing where the mulch had been. As you will know, the high acid content of the needles makes them ideal for mulching calcifuge plants.
Common stag beetle, Lucanus cervus, and a pile of oak leaves – a recipe for great compost
by Graham Petty from ‘Ask the Expert’
If like me you have many large deciduous oak trees and don’t want to burn the leaves, then turn them into compost. Various articles say they take a long time to rot down, and the result is a bit acidic. Well, my oak leaf compost is ready to use within 9 to 12 months, and my plants don’t seem to mind, whatever the pH is. The secret of my success is hundreds of larvae of Lucanus cervus, the common stag beetle, who eat their way through all the leaves and leave me with compost like the finest loam.
My compost heaps are enclosed by a 5 x 1 metre-high roll of split bamboo fencing, anchored by four poles. In early spring I fill two of these with my oak leaves, tamping them down well and sprinkling the top with any organic fertilizer to hand, and then a good soaking of water. Then I cover the top with a plastic sheet, and weigh it down with stones to keep it in place during the rigours of the Mistral. I don’t shred the leaves, but throw in any fresh green material to hand at the time to help activate the decomposition, though this is not essential.
The first year I did this, I noticed that after six months the heap had a number of beetle larvae in the bottom which were eating the decaying leaves and creating a central core of a fine loam. After nearly a year they had consumed half the heap. I riddled the heap, saved the larvae and returned them to the heap, to eat any leaves remaining from last year’s supply and start on the new year’s supply.
After three years of repeating the cycle, my compost heaps have hundreds of the larvae, which consume everything, leaving only a thin outside skin of a few un-rotted leaves. In just three months the heaps condense by half, so I top them up with leaves saved in bags. Once or twice a year I take the covers off to give them a good watering, and perhaps a light fork-over. They can easily dry out in our Mediterranean climate.
These invaluable workers are the larvae of Lucanus cervus, the stag beetle. The larvae have a cream-coloured soft transparent body with six orange legs, and an orange head with sharp brown pincers, and can be as big as 6 or 7 cms. They go through several developmental stages, taking four to six years to become pupae. The pupae, which settle at the bottom of the compost heap, resemble walnut shells. These should be saved with the larvae.
The adult stag beetle has a short life of three months or so, and some say it feeds only on nectar and tree sap. In the UK they are now an endangered species, found in only a few areas. If you have deciduous oak trees, build them a nursery, and wait for them to fly past in the early summer with their strange buzzing sound. In France it was an ancient sport of children to tie them to a piece of thread and somehow get them to fly while one held the other end, like a kite, hence their French name of cerf-volant.
The expert added:
Note on identification and a warning:
The common stag beetle (Lucanus cervus) and the rose chafer (Cetonia aurata) are both very common in the Languedoc. Larvae of these Coleoptera beetles are classically C-shaped with a well-developed head and swollen posterior.
Larvae of the stag beetle are 8 cm long and 2 cm thick with an orange-coloured head and sharp brown slightly curved pincers, whereas the rose chafer is only 3.5 cm long, often tightly curled and covered with fine pink hair.
The larvae of both species are very good at aiding decomposition and should be encouraged in compost heaps. HOWEVER, both will feed on plant roots so any compost must be free of larvae before it is used, especially when used in containers or pots.
For detailed information on identification of larvae, click here.
Letters to the Editor on composting
TMG 3 & 51995 & 1996
The Mediterranean Garden No. 3 Winter 1995/6
In issue No. 2 of The Mediterranean Garden David Fairhall asks the vexed question: Is it worth attempting to make compost in our climate?
Speaking as someone who has a garden on Mallorca, it seems that, at least on this island, there is no tradition of compost making. One possible reason might be that people who had small gardens until recent times probably also kept chickens or a pig to use up their household refuse material. Moreover, many Mediterranean trees, such as the olive, pine and evergreen oak, do not shed the large amounts of leaves that deciduous trees produce in the autumn in temperate climates.
Although Yve Menzies, in Mediterranean Gardening, speaks about improving the soil, she does not consider the possibility of compost making. Similarly, Hugo Latymer, in The Mediterranean Gardener, ‘would not recommend trying to compost ordinary garden material’ as ‘in hot, dry conditions you are more likely to find cinders than humus when you open the pile, unless you are prepared to water it almost daily’.
For a long time I accepted that view, but lately I have heard others expressing different opinions. Browsing in a second-hand bookshop, I came across A Guide to Gardening in Southern Africa, published by C. Struik, Cape Town and Johannesburg, 1975. Dudley R. D’Ewes, the author and a Cape Town gardener, says that he finds compost making a useful and worthwhile enterprise. He considers as suitable material for the heap anything that was once part of any growing thing, from old tomato plants to manure and urine. He describes his technique as orthodox, and he adds that every gardener will in time work out his/her own system which will depend on conditions and on the material available.
In this respect I find Heidi Gildemeister’s method enlightening and encouraging. In an article in Country Life (June 1995) she explains the way she improved the soil in her garden over a period of 20 years, by ‘the gradual method of mulching repeatedly with recycled farmyard, garden, and household waste’. This was done with the help of a mechanical shredder in order to break down the garden waste, and apparently the mulches once made are stored over several sites in the garden.
My final conclusion is that compost making must be ‘worth attempting’ in the Mediterranean, but one has to adapt to the particular circumstances of the area and climate. At present I cannot speak of my own experience, but hope to be able to voice it in due course.
The Mediterranean Garden No. 5 Summer 1996
Last comment on compost. I have been composting in a Mediterranean climate for 20 years in a rather disorganized manner, but without difficulty. And without watering. In two bins near the house we pile our kitchen scraps (often wet, it is true) and garden wastes, alternating as each fills up to let the pile mature. I sometimes add lime and a handful of dried blood, and we get well-rotted compost that I put around nearby roses and artichokes. This year I had to wait till spring because an animal, I think a hedgehog, chose to hibernate in the maturing bin.
In wet springs like this one I also pile garden waste (there is so much of it!) at various places where I delude myself that it does not show, and piles I made in March are already half-rotted now in early June and we may get showers once or twice in July (without hailstones, if we are lucky) and thunderstorms after August 15 (if we are lucky) before the heavy autumn rains of September (which leave a little topsoil, if we are lucky).
I don’t know why we are able to make compost – or perhaps what we get would not be considered real compost by a meticulous gardener. But for what it is worth for purposes of comparison, this is our experience.
Finally, to the compost heap: may I persuade Mr. A. M. to disregard what Yve Menzies and Hugo Latymer say about compost making (apologies to Yve and Hugo). We keep all our kitchen waste – fruit peel, potato peelings, tired lettuce, egg shells (squashed up to make them rot more quickly), anything, in fact, that we do not eat. We pile this waste into a concrete trough with an earth bottom and add grass cuttings, old newspapers and small and easily rottable waste from the garden (not large woody things as we do not have a shredder. These we burn – when we are allowed to – and add the ashes to the compost). We have just dug over the heap – after one year – and put it through a large upright sieve, supported by struts, and have obtained the most delicious dark friable compost imaginable! I cannot recommend it too highly, and if you have the space you can keep three or four heaps going and never be without this lovely dark mulch.
Although I remember compost as a household world from my childhood days in Switzerland, compost making may not have been a widespread practice in Mediterranean lands. Today, though, mulches and compost are moving more and more into the limelight. In The Mediterranean Garden No.2, David Fairhall wonders whether it is worth attempting to make compost in our climate, and in No.3 A. Martorell discusses the question at length. This encourages me to say a few words on the subject – though perhaps it may be more than a few, since I tend to get carried away when the conversation turns to mulching.
When I first came to the place which today is my garden, ‘green waste’ – as it is called today – was burnt. One knew how to build a fire and how to keep it alive. Somebody had to tend it – usually me – until all the refuse had burnt down. When materials were green, this resulted in more smoke than fire. I found the procedure a waste of time, labour and material, and as I am basically against waste I began to wonder what other ways could be found.
We started composting. A shaded spot was found under a tall and wide oak tree and stones were cleared away. Then we piled material, pulled apart or roughly cut up, alternating woody material with green material, added kitchen waste or old baskets, grass clippings in thin layers with, every now and then, a layer of soil. My young garden help trampled the heap down a bit to make it more ‘manageable’ (not too much, so that it would not compact). Whenever we had more waste, we added on to it. This was winter work and winter rains kept the heap humid. By the time summer came, it had settled down. We covered it with pine branches and forgot about it until autumn. In a ‘good’ year, the heap was watered every now and then.
When garden work was recommenced in autumn, we opened up the heap. Part of the green waste had turned into dark brown, fertile soil which was put through a sieve and handed out to those plants which were in need of help. Woody pieces which did not pass through the sieve were added on to the new heap. Sometimes there was only a little soil and much woody material, so we decided to give it another year and simply turned the heap over, making room for the new one. To speed up the procedure, after a few years we acquired a small shredder whose knives, unfortunately, required frequent sharpening and then expertise to reinstall them.
Palm leaves are ‘indigestible’ even for the sturdiest shredder, some agave leaves too. Addicted to composting as I was, I did not want to go back to burning to dispose of them. Instead, I suggested a separate compost heap in a distant but very shaded corner of the garden where this material could be left to rot for years, much against the opinion of those ‘who knew better’. Years later, the place had become untidy and a kind soul took the heap apart. To my own surprise, it revealed at its bottom a generous harvest of the finest brown earth.
At times, I tried to familiarise myself with ‘real’ composting, learned about its many advantages, remembered some basic guidelines and made a few attempts, but time was always too short (I wanted to write my Mediterranean Gardening book, take photographs for it, enlarge the plant choice, establish index cards.)
As plants grew (and thus green waste) and as the garden increased in size, we reversed the whole procedure. We brought the shredder (by now a hammermill which needs little maintenance) to the place where the winter clean-up was being carried out and fed the refuse into it, right there. Small branches, green leaves, pulled out weeds with some soil still attached to their roots turned into a good mixture. Whenever we remembered, we added whichever meals were locally available in bulk (hoof and horn, meat or fish, or bone if stronger alkalinity was desired). Variety was our aim. Once the refuse was processed (twice for finer texture), we piled the material generously around each plant (we still do), right then and there. When we finish with one area of the garden, we pull the shredder to the next one.
So, what have the results been? Gradually the mulch decomposes, more quickly in winter, and we replenish it whenever more material is available, as generously as possible. The thick layer of mulch keeps humidity in the soil and protects it from drying out in summer. Beneath the mulch fertile brown earth develops, teeming with soil life, which feeds our plants and allows them to thrive. Plants are healthy and vigorous, spared by most pests and diseases.
This rather unorthodox procedure serves my ends. Other gardeners’ experiences may differ from it, but it is thanks to mulch and compost that my garden thrives. Where 20 years ago there was bedrock, worn bare by winter rains and the hooves of passing sheep, where little more than brambles and Euphorbia survived, today I can pick flowers in my garden every month of the year, in spring enjoying wafts of scent from freesias, narcissi or jasmine, in summer walking in shade in an open Mediterranean woodland.
I manage to make quite respectable compost here in Spain, often very quickly because of the heat, by the following method:
- Create a pit, either by digging out a hole in the ground about 1x1 m square and 1/2 m deep, ensuring that drainage is good, or by using building breeze blocks to similar dimensions. A series of two or three pits will ensure a continuous supply of ready-to-use compost. I have mine under partial shade.
- Shred or chop all vegetable material available, e.g. prunings, grass cuttings, kitchen vegetable waste, wood ash, etc., but avoid weeds with persistent root systems or that have gone to seed, or anything very obviously diseased.
- Mix woody and green materials well and make sure everything is evenly damp (not soggy).
- Mix in a handful or two of a high nitrogen fertilizer (or damp down with urine).
- Fill your pit without compressing the material unduly, and cover with a plastic sheet or old carpet to keep in moisture. It will sink down as decomposition takes place. I find you can put more soft waste from the garden or kitchen on the top regularly, as it breaks down very quickly.
- Leave for 2-6 months, checking from time to time that it is still damp enough – if not, water well again.
- Sift the resultant compost to remove woody or undecomposed bits which can be put into the next compost pit or used for mulching. The compost should be evenly brown in colour and smell pleasantly ‘earthy’.
You may find compost worms active, though usually our conditions are too warm for them. More likely are a variety of beetle larvae which make a very good job of breaking down the material, but remove them before using the compost or they may eat the roots of your plants. A mass of woodlice indicates that the compost is too dry – wet it down again and they will go elsewhere. Powdery grey moulds may develop early on when there is a lot of woody material, but these will disappear as decomposition proceeds – again, keeping the material well moistened helps this.
Woodier material that has been well shredded can, of course, be used directly on the garden as a mulch and will slowly break down over a year or two. Do not dig in until breakdown is well advanced.
Likewise, green, soft material can be used for mulching but not where it will be in direct sun – put it under other mulching material or under low-growing plants.
Composting in a mediterranean climate
A discussion from The MGS Forum
The questioner’s comments are in bold
Are compost bins possible in a Mediterranean garden? All mine continually dry out.
- It's certainly possible to make compost in a mediterranean climate and many members find it invaluable both for improving their soil and for mulching. However, except in wet weather, it's essential to keep the compost heap moist by watering - which prevents absentee gardeners like me from being able to make compost. A good balance between green leafy stuff and well-chopped twiggy stuff is important.
I'm sure many of the expert composters here on the forum have some great tips for you.
- The standard compost bin which you fill up with green debris and turn at regular intervals does not work. As Alisdair suggests, you need to keep the material wet. I made my compost next to a sloping roof where water ran off directly on to the compost. You can add any nitrate fertilizer which will act as a booster. I used to throw everything on to the pile, old vegetables, clippings, grass mowings if you have a no-no lawn, twiggy bits which need to be cut down to, say, 15 cm, all weeds etc.
- Regarding composting, I agree it is not easy in mediterranean climates, especially when one is not present throughout the year. Although I am a permanent resident, I do cover mine at the start of the really hot, dry weather, making sure it is wet before I do. I use old sun lounger covers (cheap disposable ones that I replace every year) These have a layer of foam inside that gives good insulation to the pile. Over these I place a light-weight tarpaulin. When the autumn rains come I remove the tarpaulin but leave the other cover as it allows rain through but helps to keep the pile warm and decomposing as the temperature drops. In the spring I usually have a decent amount of good compost, although never enough! Of course after the summer covering a second pile has to be made to receive household waste, garden trimmings and, during the winter, ashes from our wood-burning stoves. I try to keep it "layered" as much as possible and turn it now and again but often good intentions are not always kept. However, it is well worth having a go as a little is better than nothing.
- I started a compost bin when I first arrived here in Crete. Although I was able to keep it damp, I could not turn it. This is due to an incident that happened many years ago when I gardened in Surrey. I was happily tossing and turning my compost one day with a fork. Then HORRORS!!!! I lifted my fork out to find that I had completely impaled a frog. Since that day, I just cannot do it. Every time I try, I get a vision of that poor frog. I gave up the compost bin, partly because it was so slow and partly because I wanted the space for planting as my garden is tiny. Since then, I throw my green waste on to some neighbouring derelict land belonging to the local council. Here I find, although it is slow, it does compost well.
- Composting in closed bin bags - I have not tried it, but I know it is a technique. Well, bin bags are not robust enough, but large compost bags would be.
I have no idea on recommended 'recipes' (relative amounts of green material/brown material or paper/moisture/accelerator/worms/etc.), but the idea is to avoid loss of water by keeping it in. In the Mediterranean heat, it would cook quite quickly - and I'm sure the 'recipe' makes all the difference there - you don't want to create an awful pile of smelly slime. The bag may need opening from time to time, to let air in and other gases out, I guess. Just a thought.
- Completely airtight bags do not sound right to me; composting is an aerobic process which needs a certain amount of oxygen for the microbial oxidation of carbon. Without air you create anaerobic digestion, which is fine for producing renewable energy from household waste and sewage, but I don’t think the product is as useful in the garden as proper compost.
I have a compost pile in Greece, it does not produce good compost as quickly as in my garden in Norway, since I can't water it, but it does work, slowly.
- Each year when I cut my fig tree back I place all the leaves in a black sack and that has given me a very limited amount of compost. What you are suggesting is an extension of that, and might be worth a try in the future....Thanks
I have been very busy in the garden this week. I now have enough waste matter for two compost bins. I have decided, (based on the positive feedback from this forum) to persevere. I have ordered a new shredder, and will do everything as normal. Plus water the compost daily. And once the summer heat starts I will cover the bin completely, and monitor it regularly.
No one else locally seems to compost, so I thought I was fighting a losing battle.
But I feel very positive about this method.
- Probably one of the most efficient methods of composting in our climate is with a rotating compost bin. The main problem lies in obtaining one. A few years ago a Turkish-Cypriot environmental NGO called SAVE (Supporting Activities that Value the Environment) funded by USAID (United States Agency for International Development) carried out a project in northern Cyprus involving rotating compost bins. They had them constructed from old wooden cable drums and gave them to 20 families with instruction on how to use them. At the end of the trial period 19 of them had produced viable compost, the one failure being due, apparently, to not conforming with instructions. I have never got around to following this up but anyone who has access to an old cable drum and a competent carpenter might like to give it a try. I've dug out this old photo and scanned it. The quality is very poor but it might give some idea of how the drums were converted.
- I meant to give my answer to the matter of making compost in a mediterranean climate but New Year intervened.
I don't bother. We keep all green waste from our garden but for tree branches and thick stems. I used to put it through a shredder/ mulcher but gave that away too. I detest the noise made by our many neighbours who shred, mow and blow just when I want to nap, relax, read, sit outside with friends and drinks etc so I figured the best thing to do was set the example. I just stopped using the noisy smelly machine.
Now I/we make all our green waste into a rough hand-cut mulch using secateurs etc. We usually let if fall where it drops. At first it acts like mulch but within six months it gradually turns into compost and eventually it would disappear but for us continuing to make more. In effect it is pretty much like what happens in the natural bushland hereabouts. I have a lad who helps me in the garden. He has few natural gardening talents but he can cut stuff up - which is a great help in managing green waste on site. I find I have a few ethical problems about paying to have it taken away to be dumped on someone else's land and then paying again to buy it back as garden mulch or compost.
Neat freaks may have difficulty accepting such an approach but we like it. The coarse nature of the stuff makes it the preferred home to lots of small skinks.
- I like your views on composting. There has been a long discussion here on mulching or not, but I have noticed that bushes which had a hard time surviving in the beginning, were doing much better when they finally started to produce their own mulch, then they were able manage on their own. So why not copy nature and leave the green waste where it was produced?
- I've noticed that with shrubs too - but can never be sure whether they are at last doing better because of their self-produced mulch, or whether at last their roots have got down deep enough to produce the extra top-growth and thus the mulch.
- Alisdair may remember visiting the Waite Arboretum during the GA in Adelaide. The Curator and staff there spread shredded tree branches and dried gum leaves in thick carpets under all the trees in the collection to the extent of the drip-line and beyond. The trees get no irrigation after they are established and are doing really well. I think Alisdair will agree that the arboretum looks in good condition.
- I would not be able just to cut and leave. Personally I like everything in its place, and that would not bode well.
I too was disappointed with the shredder ( I was expecting big things). I ended up cutting everything down to a smaller size before putting it in the compost bin. I have placed a black membrane sheet over the compost bin, which allows me to water it without removing the sheet. Then once a month I will turn it.
- I used to turn my compost until I slipped a disc doing it. Now I don’t bother and the compost is just as good.
As far as letting litter build up, a couple of comments. Not a good idea for roses, apples etc where diseases will overwinter. Also some callistemons produce chemicals which will inhibit plant growth.
The garden we bought was full of mature evergreen oaks and the resulting leaf litter was many cms thick.
- Re compost making: we have erected a circular metal frame, made from what we think is concrete re-enforcing mesh, and surrounded it with olive netting and plastic sheet. The diameter of the compost bin is about 1.5 m and its height approx 1.3 m. All the weeds we pull up go in there, together with kitchen waste. We leave it open to the rain in winter and cover it in summer with more plastic sheeting. We have connected it to our drip irrigation system and in summer it gets watered once a week. The middle of the pile produces some decent compost but the edges just dry up. The dry parts can of course be added to the following year's pile.
Note from Caroline Harbouri on composting in black bin bags:
As to plastic bin bags, I used to make leaf mould in them. All the autumn fallen leaves that I swept up went into black plastic bin bags which I sealed and tucked away in the shade in an out-of-the-way part of the garden. At least some of the leaves were damp when I swept them up. By the following year when I opened the bags I had perfect well-rotted leaf mould. This worked so well that I asked a neighbour who had a garden for all the plane tree leaves she swept up... I also used bin bags to store fresh horse manure mixed with straw that I’d collect from a riding school: after a year it too was well-rotted.