Renewable composts - are they possible?

[David Nicholson]

Thanks for that Paul, it is really good stuff. That is why I now do a round trip of about 200 miles just to buy Green Ore compost. Pity if you had to give it up!

[Stephen Vella]

Im surprised nobody mentioned coco fibre (coco nut hasks) which acts like peat and is a recycled product and theres plenty of coconuts on this side of the equator!

As an additiion to our potting mix our nursery uses it for growing all sorts of plants and we are a cool climate garden with alpines included. Our mixes contain quarts sands, composted fine wood chips, coc fibre, perlite if needed, zeolite and clinker. The Aussie nursery trade uses similar mixes.

Most of these products are recycled products or man made ones except for the quarts sand which is being mined. We use to use river sand but stoped.

In the EU you can get your hands on Seramis which is a fine man made product with cation exchange, absorbs water and nutrients.

hope this helps

[gote]

Environment questions are tricky. In some ways I am reminded of the old proverb: However you turn, your tail is on your backside.

Coconut fibre, leaf mould, bark and peat are renewable materials in so far that they grow naturally and would not have any other uses. In a temperate climate, leaf mould decomposes and releases the nutrients it contains into the soil where the trees grow. The same goes for bark. If we use the bark for horticultural use we (to a small extent) remove nutrients and soil conditioners from the forest. However, most bark in the market is a by-product in saw mills and would not be shipped back to the forest anyway.
 
Peat is different in that it does not decompose in the place where it forms. It is a growing resource. In the countries east of the North Sea it has filled a very large number of lakes and this is an ongoing process. People who like lakes, fishes water lilies and aquatic fauna and flora generally have some difficulty in understanding why the very barren peat bog should to be preferred.

Peat bogs cover approximately 2% of the total land surface of this planet and the total reserves today is assumed to be about 3 trillion cubic meters. In peat rich countries it is mined and used for fuel. Horticultural use makes an exceedingly small dent in the peat resources The main point is, however that the peat resources are growing faster than they are consumed and the amount of peat in the Scandinavian and Baltic states is steadily growing.

Searamis is clay that is mined in Westerwald in Germany, foamed and fired. This means that a non-renewable recourse i.e. the clay is burnt in a high temperature process presumably using another non-renewable resource i.e. oil or coal releasing CO2 to the air. However, the production of Seramis is probably insignificant compared with the large amounts that go to clay brick and earthen ware.

Quartz sand is an important raw material in i.a. glass making and from the horticultural point of view sands containing feldspars and other more complicated minerals are equal (and vastly more abundant) as long as they are not carbonate minerals (lime stone, dolomite etc), which change the pH of the soil. It can be argued that feldspars are better since they release potassium but the amounts are negligible in practical use. In most parts of the world sand is very abundant and sand of horticultural grades, is often a by-product in the mining of gravel. Sand is indestructible and it doubtful that there is something wrong in moving some of it from a deposit in a sparsely inhabited area to a garden in a town. This provided that the mining is not too destructive in itself. The sand in a pot of John Innes has a longer life expectancy than the town in which the pot stands.

The important issue is not whether we use a specific material or not. The important question is: Where and how did it originate? To use horticultural peat from a Baltic deposit is hardly detrimental to the environment. To mine peat in the only peat bog in an area where there is no formation of new peat and where bogs are rare is of course not environment friendly. To destroy a river sand bed is not to be commended. To use a by product from a gravel operation that otherwise would be dumped should not pose any problems.

Cheers
Göte

  

[Stephen Vella]

Yes Gote like you say depending on the source and if its a renewable one. Peat bogs in Australia isnt as we dont have much at all. Back in the 80s when a peat bog was being dug up it collapsed and washed away and with it a rare vegetation type that relied on the peat supporting it. It was an ecological disaster and one not to be repeated. So when the resource wasnt there we tend to improvise and look elsewhere. Dont really see peat on the shelves in markets, i dont think its imported anymore.

Interesting what you say about Seramis.I see why its expensive. 

cheers

[Paddy Tobin]

A local solution: our local corporation collects all compostable material from homes in the town and sells the resulting compost.(3 euro per 45 litre baf) It is good quality, slightly alkaline and perfectly suitable for the vegetable patch, at least. In the last week I have collected about 40 bags from the composting facility - it is being given free for the month of September. An information leaflet from the facility says it is also suitable as a mulch in the garden and as a  potting medium.

Paddy

[David Pilling]

A local solution: our local corporation collects all compostable material from homes in the town and sells the resulting compost.

Some councils give away such compost - I wonder how free of pests and diseases it is?

[Paddy Tobin]

David,

I would be confident of the safety of the compost given the temperatures reached during decomposition - huge volumes of material lead to very high temperatures.

Paddy

[gote]

A local solution: our local corporation collects all compostable material from homes in the town and sells the resulting compost.

Some councils give away such compost - I wonder how free of pests and diseases it is?

We have it here in Örebro too and it is quite good. Only problem is alkalinity since I grow several lime haters.
I have never found a single weed in it. Nor any pests nor diseases but the latter may of course be there without my noticing it.
It is quite useful to augment the soil I use for Numphaeas.
Cheers
Göte
 

[Regelian]

It seems we have already addressed most of the typical compost ingredients.  I have spent the last 10 years exploring various elements for potting and bed mixtures, as, living in a city in Germany, I cannot simply go and pick-up a bag of manure or John Innes!  Sounds silly, but there are no local garden centres that carry truly 'raw' ingredients.  One has to get inventive and try other items out or take a day in the country and rob some stalls.

Finding a basic, such as loam, is close to impossible, unless one wishes to have a truckload sent in (and then it is full of weeds and hardly deserves the name loam).  I have taken to mixing cocos (coir) with lava gravel (used for de-icing) and play-box sand to get a basic mix.  Composted bark is added to create a more woodland or acid mix.  When I need gravel, I buy basalt split.

One thing to keep in mind with bark; it will take-up most of the nitrogen in fertilizers, until it starts to really breakdown itself. This is due to the bacteria doing the breakdown.  After the process is completed, the bark will start to release the nitrogen back into the soil.  This can be a problem in a pot!

I have stopped using peat for a number of reasons.  Firstly, it hold much too much water for a potting mixture in my climate.  People buy it as a mix for their window boxes and the poor plants simply suffocate for lack of air at the roots.  In general, coir has proven a better choice for me. Secondly, it drops the pH of the soil.  Then there is the ecological issue, which has been discussed, but, frankly, this is certainly over-played!

I have recently started using a commercial coir mix, which is touted as saving our peat resources, of course, but find that its relatively open structure is just what many of my plants like.  Open structure is a real issue for me.  I use gravels and sands to lighten mixes, but they do add considerable weight.  Perlite is rarely avaialable, as the market product in Germany is fire retardant and designed as insulation, not for the garden.  Occaisionally, I find a bag of the basic stuff and buy what I can transport. The last time I saw vermiculite was in England.

In the end, it is very frustrating to find garden safe products, if you are not a commercial gardener, as the main uses of many items is not gardening.  On the continent, I often get the feeling that gardening has become politically incorrect!  Mind you, that has never stopped a true gardener.  And there are still quite a few over here, thank you.

In the end, I am very happy with coir as a peat substitute and simply gather as many leaves from the streets in Autumn that I can.  If only a cow would wander by....or, maybe a horse.

[SAMTHEBAM]

free vermiculite is obtainable from your local Honda dealer if you go and ask. it comes as a packing agent around new batteries .  my local garage keeps it for me and i use it in my compost mixtures .

[Maggi Young]

Hi, Samthe Bam, welcome to posting!
Now that is an extraordinary tip about the battery packing........ who'd have guessed that! 

[SAMTHEBAM]

i know this is not a compost , but this  is another  reusable item from the motor industry.  many bumpers come wrapped in bubble wrap (especially Honda's) with white diffused foam on the inside which is excellent for greenhouse shading , these come in large sheets and are best obtained from a auto bodyshop .

[cohan]

i come to the issue of potting media from the direction of cactus and succulent growing, where there is a HUGE  amount of discussion of the issue..
as carlo mentioned, for most plants, the substrate is only one issue, and there are highly successful growers using mixes that others would swear are a death knell..

for those sorts of plants (cacti and succulents) i avoid peat like the plague--unless you are constantly repotting, like a commercial nursery, many of whom do use it for cacti, it breaks down into some concrete like substance--it took me weeks to wash it completely off the roots of my (indoor) collection when i switched to loam based media (when i was still living in toronto);

this wasnt easy to get in downtown toronto, as most commercial mixes in ontario have peat and are based on composted bark, which is also supposed to be not that great for c+s, due microbial and fungal activity which plants from arid places are not adapted for, but i was able to go to a retail gravel supplier and buy self fill bags of
rather clayey loam... this was mixed with various kinds of grits and gravels, coir and crushed brick-something european growers of c+s are fond of..

perlite and vermiculite are readily available here, but i reject them on aesthetic grounds--esp perlite which inevitably floats its hideous self to the surface; nothing worse to me than seeing a beautiful plant surrounded by those artificial white beads;

now, living in the country, my approach is totally different, since i can harvest several types of soils/amendments (clayey loam, black wooded soil, peaty stuff, decomposed animal manure, composted leaves, conifer duff-if i had a reason to!) from my own acreage,  but most of these base items fall in that not useful to recommend to the general public;
 i still need to buy grit (usually poultry grit, and zeolite, like a sharp artificial sand) and coir to open up especially the clayey stuff in pots; coir is very available here, now..

[iann]

Hi Cohen, I'm in more or less the same position and start my mix with John Innes.  I grow mostly Lithops, highly xeric cacti, and some other succulents, but also some alpines.  I would imagine that peat isn't the first choice of most alpine growers, but then a surprising number of C&S growers still use it so I might be wrong.  Outside the UK (and Oz and NZ?), standardised loams like John Innes are difficult to find and ingredients like coir are much more popular.  I know JI typically is about a quarter peat but I'd happily do without that quarter.  I've successfully grown in loam from my garden, plus aggregates for drainage, but it is highly alkaline and a little inconsistent for use with small potted plants.

I feel it is a shame that newcomers to our areas of growing will be directed to possibly the worst starting point for stable free-draining soil, which is a bag of peat with a little perlite if they're lucky.  I struggled for years before I realised that the stuff in the garden centre that says Cactus Soil is nothing of the sort   Mixes based on high proportions of bark or coir would be a far better introduction and there would be no need for beginners to learn how to work around the limitations of peat.

[cohan]

Hi Cohen, I'm in more or less the same position and start my mix with John Innes.  I grow mostly Lithops, highly xeric cacti, and some other succulents, but also some alpines.  I would imagine that peat isn't the first choice of most alpine growers, but then a surprising number of C&S growers still use it so I might be wrong.  Outside the UK (and Oz and NZ?), standardised loams like John Innes are difficult to find and ingredients like coir are much more popular.  I know JI typically is about a quarter peat but I'd happily do without that quarter.  I've successfully grown in loam from my garden, plus aggregates for drainage, but it is highly alkaline and a little inconsistent for use with small potted plants.

I feel it is a shame that newcomers to our areas of growing will be directed to possibly the worst starting point for stable free-draining soil, which is a bag of peat with a little perlite if they're lucky.  I struggled for years before I realised that the stuff in the garden centre that says Cactus Soil is nothing of the sort   Mixes based on high proportions of bark or coir would be a far better introduction and there would be no need for beginners to learn how to work around the limitations of peat.

ian, i'm ashamed to say i've never done any kind of testing on the native soil here, so while i assume its relatively alkaline, i couldnt say for sure--i'd say more so than in the wet areas here, or in the heavily spruce parts of the woods, and presumably less alkaline than in drier less wooded parts of canada's west..but those are rather vague assumptions...i really should read about it more (i've started that a bit) and do some soil testing--never done it, but i suppose materials for that should be easy enough to get?

i've had excellent results with those plants i have started or repotted since i got here--including seeds i have started-using the native loam (couldnt really say 'garden soil' as its not taken from any pre-cultivated areas, just spots i am either digging new beds, or digging for some other reasons; it sometimes scares me as very clayey, but plants dont seem to mind, at even 50% with coir and grit/zeolite;
note, for some seeds of more woodland things, i replaced the clayey loam with soil from a pile of topsoil left from an old sewer excavation--more at the edge of a wet area, this is blacker soil, still loamy, but clearly much higher organic content..