Tuesday, 29 March 2016

The variety of jobs that need doing at the end of March.

The composts are always an ongoing job and I have been given a variety of different materials to put into the compost bins.  Many allotmenteers will have been taking down runner beans and I have been going round asking if I can have the old plants for the compost bins.  It seems that people are only too pleased to get rid of them and it avoids them being burnt and messing up the fresh air.  I have also been given rabbit bedding which is a mixture of sawdust and hay intermixed with rabbit droppings and urine.  These additions to the compost heaps will break down and form a good compost to add to the soil.  I will probably add the compost to the surface rather than dig it in primarily to avoid unnecessary soil disturbance. 

Another item that has been added to the compost bins is the charcoal I made last week.  This charcoal is very alkaline and full of concentrated nutrients.  It really needs to be composted and diluted to make it more suitable for adding to the soil.  There is a danger that adding the charcoal to the soil directly would produce an excess of nutrient salts and damage plants.  Added to the compost and mixed with various other constituents will enable it to become less concentrated and more appropriate for adding to the soil. 

I am adding shredded material to the compost bins.  The load that has just been delivered is full of leaves and this will aid in its decomposition.  The more leaves and green stems the more nitrogen there is in the shreddings and this helps with the decay process.   I needed to get rid of some subsoil when I was triple digging during January 2015 so I stored it under the hedge behind the shed.  It is amazing how much room this took up.  I am now using this subsoil to add to the compost bins. Mixing in a great variety of different organic matter together with various nitrogen sources will turn the subsoil into a more top soil like soil. I also added a douche of dilute comfrey and urine liquid particularly to the dry ingredients. 

All the bins were turned and they will be again in two days time.  The woody material that I put back into the bins, after sieving the compost last time, is beginning to go very brittle and easily broken up into smaller and smaller pieces. Although they will not be fully decomposed, they will go through the bread tray sieve and this is my criteria for putting it onto the soil surface as a mulch. 

It was a warm beautiful afternoon last Thursday and I decided to have a go at grafting the apple scions that I have been given.  Some of the root stock was particularly large so I had to try some different grafts.  I think that I have some good grafts but I will wait until July/August before I review how many have actually taken. 

After planting the sweet peas, I had all the root trainers left empty and rather just putting them  away, I decided to use them for the leeks.  So all the root trainers have had a replenishment of potting compost and a leek transplanted into them. The Musselburgh and Blue Solaise I sowed earlier in the month have grown into quite strong seedlings and needed to be transplanted.

I have planted some of my own seed sweet pea plants to grow up the wire supports that I put up for the loganberries and blackberries.  This will do two jobs.  One is to produce more nitrogen fixing bacterial which will provide a little nitrogen for the potatoes and another is to make the allotment a little more colourful.  I will not take off the tendrils or side shoots but just let them clamber over the wire mesh as they will. 

I sowed parsnips Pastinaca sativa and skirret Sium sisarum today.  I sowed them in the soil that had not been manured this winter.  I had dug in the pea plants from last season and put a top dressing of compost on the surface to improve the soil but nothing else.  It is said that if you dig in compost or manure then the parsnips will fork and form distorted roots.  I don't know if this is true but it is no difficulty in taking this into account in preparing the soil.   It is a lot easier to prepare a smooth thick root for cooking than one that has numerous side extensions.   Apart from mulching them when they have grown about six inches tall with shreddings, I doubt that I will do anything else to these plants until I harvest them.  I expect I will have to do some weeding along the rows but I am hoping that I will have very little weed this year. 

I have moved all the apple grafts over to beside the little shed.  The idea is to stop me from fiddling with them; stepping on them and to put them out of my mind so that in June or July I remember they are there and I will be surprised that they have all taken.  Although they will be in the shade for most of the day, I will have to make sure that they are kept moist but that is all that they will need until they get planted in the growing beds.  Where I am going to plant them is a good question because I have no room at all for this many apple trees espaliered or not.  I may see if I can cordon them or make them into step overs.  Probably the only way I can keep them all. 

I have put the big green tarpaulin on the big shed roof because it was leaking.  I folded it into four and it fitted onto the roof almost exactly.  I had to weigh it down because of the strong winds this weekend but it is keeping the shed dry.  I will have to get some more shed roofing felt and redo the roof before next winter but until I do the tarpauling can be safely stored on the roof. 

I have had to put a centimeter square net over the broad beans to keep the mice off them.  I have pegged it down with the tent pegs that I found in the compost I made from the weeds on the carpark allotment area.  I am glad I kept them because they are becoming very useful. 

I shall  have to buy some more steel tipped gardening boots because mine are becoming more and more ragged.  I know that I use them almost every day but I would have hoped that they would be a little more robust than this.  However, I was looking at my gardening gloves as well and they do not seem to last more than one winter's hard work.  So really the boots have lasted me a good three or four years and I have to be grateful for this. 

The jobs that I still have to do are:
Continue digging out the subsoil from behind the shed and composting it.  Then rearrange the storage area to give me more room for the comfrey and worm bins. 
I might plant some of the early potatoes although it is forecast for some frosts on Thursday and Friday so the potatoes might be best left covered in fleece and bubble wrap in the greenhouse.   I think that I will plant some more elephant garlic because I use a lot of this in stews, curries and soups.  I just have to leave some room for the red onions to go in.  I am planning to plant the oca tubers in this growing bed too. 

I need to continue putting in paths between the pea beds.  I have dug out some paths putting the soil on the growing areas to raise them a little.  I put cardboard at the bottom of the shallow trenches and made up the level with shreddings.  I have some newspapers that I will put at the bottom of the shallow trenches for the next paths.  I'll cover these with shreddings and hopefully this will suppress the weeds a little. 

I need to sort out the peach greenhouse and put the ring culture pots along the walls.  I will not fill these with compost until the tomato plants are ready to be transplanted into them but it means they are ready and not taking up room in the store shed.  (I need to tidy the store shed).

I need to check that the giant Victoria rhubarb is growing directly under the dustbins.  As they had died right back I just made a guess to where the plants were when I covered them with the dust bins. 

I need to tie in the redcurrants I planted next to the composting area.  I want to keep them to the fan trained shape so I will tie them in carefully. 

Although there is not much to see, I might take a few photographs for the end of March. 

Thursday, 24 March 2016

Planting out the sweet pea seedlings.

I have planted the sweet pea seedlings next to their cane supports but I have a lot of seedlings left over. 
I might put some more canes along the rows and add some more plants and these can be replacements if any of the main seedlings die. 

Some of them I will plant in the flower garden but the others will be planted around the allotment as nitrogen fixers - and to give a little colour. 

It is a good thing that I sowed some of my own collected seeds because I would have very few if I had relied on the bought seed. 

I think that I have a good selection of colours but the only way to be sure is to wait until they flower in June. 

Three of the crab apple pips have germinated.  They will not probably have the same characteristics as the parent but I am not to worried about that.  I want the blossom because that will help to fertilise the espaliered apples.  They will be transplanted into three inch pots of their own and grown on in the greenhouse until they are big enough to plant outside. 

All the compost bins have been turned and watered with comfrey liquid.  They were getting dry and this slows down the decomposition process.  As much of the material has been sieved and generally shaken about, it was very friable and full of air.  I am getting regular bags of rabbit bedding now and this is being incorporated into the composts.  Some of the subsoil I put under the hedge at the back of the shed is being added to the compost as well.  This is making the storage area at the back of the shed much bigger and allowing me to make a more top soil like compost from the subsoil. 

I have put all the canes up for the tall peas and French beans.  It is a little early to be bothering with this but I wanted to clear around the back of the shed where they were being stored and I needed to know how many canes I had to add to the sweet pea rows. 

I dug out alleyways between the French bean rows and threw the soil up onto the beds.  This raised the level of the beds and gave me a good planting area.  The alleyways were filled with shredded woody material. 

For the first time for many years, I have planted quite a few onion sets.  I got two bags of freebee sets and this was far too many if I was growing from seed too.  I have still planted all the sets because I can always weed out the rows of sets that I do not want and replace them with varieties grown from seed. 

I have covered the onions sets with enviromesh to keep the miner fly away from them.  As weeding along the rows is very difficult when there is a net covering the sets, I covered the ground with a mulch of woody shreddings.  This did a really good job of keeping the onions free of weeds last year.

I made some more charcoal today.  I don't think that it has been as successful as it was last time but I haven't tipped out the inner charcoal container yet.  I am composting the charcoal I made last time.  It has been marinating in comfrey juice for about four weeks now.  I want it to be incorporated into the compost so that it is diluted.  The compost will be spread over the brassica bed. 

I am going to cover the shallots with enviromesh or scaffold netting because they are affected by the miner fly as well as onions and leeks. 

The ordinary garlic is growing tops about ten centimetres long now. 

I will be grafting this week and the beginning of next week.  I have all the equipment I need now to do a fairly good job.  I will bench graft in the greenhouse.  All the rootstock is potted up and just waiting for me to finish other jobs around the allotment.  I need to sharpen the grafting knife. 

Monday, 21 March 2016

Start of the main seed sowing season.

So I've sown more seed although it is still quite early and cold.  Peppers, cucumbers, melon and aubergine all need to be sown quite early otherwise you do not get a ripened crop.  They need a long warm summer or a heated greenhouse to really produce a lot of fruit. 

More leeks and onions - including red onions; cabbage, cauliflower, calabrese and some more herbs were sown into three inch pots.  This restricts the amount of seed that is used. 

I put the broad beans into sectioned trays and my own broad bean seed straight into the soil on the beans and pea bed.  I covered over the bean seed with some wire netting to deter the rats from digging them up and eating them.  However, I checked today and something has been digging up the broad bean seeds and eating them.  I will either have to put a better net over them or just leave them and plant some dwarf French beans where they are now. 

I also sowed some more tomato seeds.  They are the cherry tomatoes and they produce quite a lot of fruit once they get going. 

The Alicante and Black Russian tomatoes are surviving and growing well.  I have transplanted them into three inch posts so they can grow on.  Once they are about 150mm, I will plant them into the big pots. 

I have transplanted all the winter sown onion seedlings into sectioned trays and will leave them to grow on until they are about 150mm tall.  I still have to transplant the leeks. 

I have put up the cane supports for the tall peas.  However, before putting the canes in, I dug alleyways putting the soil on the beds and slightly raising them.  I replaced the soil with shredded woody material which made a very good path. 

The canes for the tall peas were put in at 300mm intervals which is adequate for these vegetables.  I will cover the canes with netting to give the peas something to climb up. 

The canes for the climbing French Beans have also been put up in a similar way.  I wanted two rows of canes because I have so many different varieties of climbing bean. 

Most of the sweet pea seedlings have been planted out under the cane supports.  I will select the best shoots to tie in and take up the canes.  Any other shoots will be cut out and composted.  I watered the seedlings in with very weak comfrey liquid.  As there is charcoal marinating in the comfrey liquid dustbin some of this found its way into the watering can and from there into the planting holes.  The charcoal will give the sweet pea seedlings and additional boost.  Once I have planted out all the sweet pea seedlings, I will have a little more time to do some more seed sowing.

The first set of seed that I will need to sow is the parsnips.  I also have some skirret seeds which I will sow next to the parsnips.  I have never grown these before so I will be interested to find out what they taste like.  As parsnips have become a lot more popular, I suspect that skirret is not particularly tasty. However, together with Hamburg parsley, they are another root vegetable that can be used in vegetable stews and curries. 

I still need to cover the onions with enviromesh.  The leek miner fly Phytomyza gymnostoma  is very prevalent in the West Midlands and alliums need to be protected from it. 

I have just got all my stuff together for grafting.  All the buds are beginning to break now and it is obvious, bad weather or not, spring is here.  The forsythia and the flowering currant are flowering and I have seen magnolia coming into bloom. 

I will start the grafting towards the end of the week when I have finished everything else.  I am looking forward to that.

Wednesday, 16 March 2016

Allotment jobs during the middle of March.

I went to the edible garden show in Stoneleigh Park Warwickshire on Saturday and met Big Gee of the Gardeners' Chat Shed Forum and Sean from the Horticultural Channel. 
Gwilym ab Ioan(Big Gee) at the edible garden show.
Both lovely people who had time to say hello.  The show was very good but most of the things that I wanted to buy were way out of my budget at the moment. However, I was very tempted to buy a mulberry tree but would not really have anywhere to plant it.  I will have to make do with the fruit I've got already. 

I also went to the Gardeners, Question Time recording which took place on Saturday.  It did nothing to impress me. The audience was entirely white Middle Englanders and I include myself in this description. I submitted two questions neither of which were asked; maybe a bit difficult for this panel of pundits. I asked one about using charcoal and another about whether adding mycorrhizal fungi spores was worthwhile.  It was freely admitted that the programme was primarily entertainment rather than educational.  That sums up its usefulness to serious gardeners. 

The M9 rootstock have come from Sheep walk Nurseries and I must say that they are a little bigger than I was expecting.  They are about 10mm in diameter at the tops.  I should not have thought that I was going to get pristine rootstock because I ordered them right at the end of the season.  I was toying with the idea of sending them back but then I thought that it would be an additional challenge to see if I can graft onto these larger rootstocks.  I have potted up all the rootstocks and will bench graft because this gives me a little more control over the procedure.  I will do a side graft with a tongue.  Last year I grafted on the twenty first of March so I will try to do the same this year.  I have a lot more scions than I had last year so it will take me longer to complete the grafting. 

I am going to melt the beeswax in a camping pan over a camping gas burner.  I used a candle to heat the wax last year and it wasn't very successful. 

It may be a little early but the Peregrine peach budding does  not seem to have been successful.  All the apples seem to have taken though.  But I don't really want four Cox's Orange Pippins.  The three still in their pots will be used as rootstock for some of the new scions I have this year.   If all the new scions grow this year I will have a collection of twenty eight different varieties of apple.  The majority of which will be heritage varieties. 

Usually heritage varieties are prone to disease and crop poorly - that's why they are heritage.  However, apple varieties are different.  The Victorian gardeners certainly knew what they were doing when it came to apples.  All the heritage varieties are very good apples and not necessarily any more susceptible to disease than modern varieties. 

The only way that I am going to be able to fit all these trees into the allotment is to espalier them and keep them fairly well confined to smallish areas.  If push comes to shove, I will have to make a choice about which apples I am going to keep and which I will give away.  However, that is jumping the gun a little because there is no guarantee that all the grafts are going to take. 

I have put up all the sweet pea canes and went on to put the canes up for the runner beans.  I will not be sowing the runner beans until April but it is another job out of the way.  I dug out alleyways for the paths between the sweet pea rows and put the soil from them onto the beds.  The alleyways were then filled with woody shreddings.  This makes a very acceptable pathway between the rows. 
Four rows of canes for the sweet peas and one row for the runner beans.  The canes were
tied up at the top with gardening wire.  This is the simplest of constructions for the supports
It makes a strong structure that rarely falls down. 

Sweet pea seedlings in three inch pots.  They have been hardened off for about a week now
so they will be ready to plant out. 
I will start to plant the sweet pea seedlings tomorrow.  They will be planted with a little mycorrhizal fungi and watered in with a weak solution of comfrey liquid. 

Although I try to turn the compost every two days, I have had a lot of other jobs to do so this has not been adhered to strictly.  However, as I was turning the compost today, I thought that it was probably good enough to use on the growing beds now.  I used the bread tray sieve to separate out all the large undecomposed material and returned this to the Dalek bins. 
The compost from the bins after it has gone through the bread tray sieve today.  It is amazingly
friable material that looks just like proper compost. 

This is what the compost in the Dalek bins looked like on March 4th.  By the 16th it had
rotted down significantly so that a very reasonable amount would go through the
bread tray sieve
There was a dip in the soil on the root vegetable bed so I decided to spread the compost over the surface to level it up a little.  I got about six barrow loads of compost sieved from the bins and I put it all on the root vegetables bed. 
I just raked the compost over the surface to level it.  I will be sowing parsnips and carrots here
The scaffold netting in the background is over the grape to protect it from the cold winds
during the winter

I sowed some more onions, savoy and red cabbage, and more cucumbers.  The cucumbers that I sowed in February have died so I needed a replacement. 

I know that it is a little early, but I have taken the damaged branch off the big Victoria plum tree.  It was irritating me that I hadn't done it.  The branch went into the Hugelkultur trench. 

It will be another busy day tomorrow. 

Sunday, 6 March 2016

Trenching the pea bed.

I am not going to do any more trenches, however today I dug a couple to bury some of the woody material I have bought from home.  I had not dug over the new pea bed so it gave me the opportunity to get rid of the prunings easily by putting in a couple of trenches here.   There were some white beam prunings, some shrubby honeysuckle prunings and various other bits and pieces.  I also wanted to empty at least two of the compost bins so that I could put the bins over the rhubarb.  I want to force the rhubarb a little so that it tastes a little sweeter when I add it to crumbles and pies. 

Taking out the first spit. 
Same part of the allotment September 2013.  The whole allotment had weeds like this so I covered it with carpets.  In
order to remove all the weed rhizomes, I triple sieved dug adding organic matter as I worked backwards down the
There were a lot of fungal hyphae growing on last years woody shreddings mulch. 
Fungal hyphae on last years mulch.  The whole allotment was mulched in 2015 and by the
end of the season it had all but decomposed.  The last of it was dug into the soil during
the winter.  This has added a lot of organic matter to the top soil. 
As the material I wanted to bury was woody, I decided to bury it under a spit of sub soil.  So I had to dig out another spit of soil.  It is a little hard work to take out another spit of soil and put it on the side so I decided to just take out a little, put it in the wheel barrow and leave it next to the trench but at the other end.  This way I had a deep hole to add the woody material to but I did not have to take out the second spit for the entire trench. 
The second spit taken out. You can see the organic matter, added in 2013 and in the photograph
below, has decomposed leaving mainly the very thick wood. 

Trench in the same part of the allotment 2013.  The soil does not have very much 'body' to it and the sandy clay texture
is quite obvious.

I dug down another spit to see if I could find the woody material I put at the bottom of the trench two years ago and started to find some of the thick stuff.  All the finer material had completely decomposed leaving only traces behind. 
Adding woody organic matter in September 2013.  I needed to improve the organic content of the soil and the only way
to do this was to triple, sieve dig adding as much organic matteras possible.
The soil was replaced and just forked over to make sure that it wasn't compacted.  I added quite a lot of woody organic matter.
Added woody material.  Now that a lot of organic matter has been added to the soil, its
fertility and water holding capacity is slowly improving.  However, I will still continue to
add as much organic matter as I have available.   

I dug out a spit of subsoil from further along the trench to cover the prunings.  This was not done particularly carefully because it was going to get raked to level it off. 

The white beam prunings.   This will include large logs, branches and brushwood.
I am not at all concerned about adding the thick branches.  I cut them to about six inches long and I have found that when this is done they decompose relatively quickly.  However, I don't want this material to rot down too quickly because it will produce a sponge that will retain water that the peas will be able to access.  I kept adding and covering the woody material until I reached the end of the trench and then used the pile of subsoil on the side to finish off the covering.  I used the rake to level off the subsoil before adding the top soil to fill the trench in.  Once I had done this, I used the rake to level off the top soil.  As you can imagine, this raised the level of the soil a few inches and this is what I wanted because the soil had slumped down on this bed.  Probably the organic matter I added two years ago had started to rot away and the soil had dropped as this happened.  I am hoping that I have added enough to raise the soil again and be able to level it off.

Same part of the allotment September 2013.  A great deal of top soil had been removed by
previous allotmenteers when they had bagged up the weeds and taken them to the tip.  This
left a stony, sandy clay soil with very little organic matter or soil life.
Lots of organic matter added to the trench in 2013.  All this organic matter has decomposed only leaving the very thickest
of the wood.  The allotment soil has been raised about eighteen inches above the level of the track way. 
The soil has changed a lot since I took over the allotment in 2013.  It has got a lot more body to it now and is much more friable. 
Although I had several bags of this organic material, I did not have enough to fill the trench for the whole length.  I emptied two of the Daleks of compost and wheel barrowed it to the trench.  There was just enough to fill the trench to the end.  The empty Dalek compost bins were used to cover the Victoria rhubarb.
Empty compost bins over the rhubarb.

Same area of the allotment 2014

None of the Victoria rhubarb is showing yet but I like to get the bins on in good time.  Picking the rhubarb and making the first rhubarb crumble means that spring has really begun. 

I will be planting the peas in sectioned trays later on this month.  My first sowing will be "Douce Provence" and they will be planted next to but two foot away from the vine supports. 

Another sign that spring is just around the corner is the peach flowering. 
First flower on the peach. 
The other buds are just showing colour
I might go around and touch each of the flowers with a very soft paint brush when more of the flowers are open just to make sure they are fertilised.  I would like to get at least one peach this year and I don't see why I shouldn't.  The tree seems to be very healthy and is producing quite a lot of flowers this year. 

I had a look at the remaining wood that I have for charcoaling but it was still very wet.  I need a couple of days of dry weather before I can light a new charcoaling fire.  There is more than enough wood to charcoal and to use for the fire.  Any wood that is left over this time will be buried in the subsoil. 

The bushes I planted alongside the carpark are not red currants but black currants.  This would not be a problem but the bushes have big bud.  Either I will have to take them out or cut them hard back to ground level.  This is a little disconcerting.

Friday, 4 March 2016

Early March Compost

The new composts that have been on the go for about two or three weeks now have not started to decompose very much yet.  They have changed colour to some extent although there are some things that are still green.  The woody components are starting to become brittle and are much easier to break into smaller pieces.  I chop them up using the shovel. 
Woody compost material slowly changing colour. 
The problem is that I keep on adding new material to the bins.  Having to wait for this to decompose means that the compost is taking more time than usual to break up into smaller pieces.  There is a marked decrease in volume leaving space for more material to be added.  I need to resist the temptation to put more stuff in the bins.  I have used a lot of woody shreddings in all of this new compost to see if it will rot down quickly. 

The change in volume could be a result of two things.  There may be a breakdown of the material into carbon dioxide and this will be lost from the heap as a gas or there may just be consolidation of the material.  Consolidation is more likely to occur when the compost breaks down into smaller pieces allowing it to fall into the voids produced by larger more resistant pieces of compost. 

All the bins have similar material in them.
The bins are being turned regularly but not necessarily every two days.  This may be why they have not begun to decompose very quickly, although this lack of decomposition is more likely to be a result of the cold weather.  Even though this compost is not rotting down very quickly, it is breaking up into smaller pieces fairly rapidly. 

After taking the bins off the compost it leaves a neat pile that can easily be put back into the bins. 
Although it is not decomposing very quickly it is changing colour and breaking up.
The neat "sand castle" like piles fall apart quickly and need a shovel to put them back into the bins. 
Refilled green bin.

This compost consists of woody shreddings; prunings from blackberry and blackcurrant bushes; weeds and kitchen scraps.  There is orange peel in the compost and this will break down very quickly once it starts to decompose.  I have also put quite a bit of cardboard into the bins but this rots down remarkably quickly just leaving the plastic sticky tape that was holding it together and a few plastic labels.  I didn't see any cardboard when turning the composts today. 

There are still some bindweed, horsetail and couch grass in the bins and these are regenerating a little so if I see any rhizomes with buds, I take them out to dry for a week. 

There may be some that stand aghast at the materials used to make this compost but these are the organic materials I have at hand.  And they do rot down.  Admittedly they rot down a lot quicker if they are shredded or broken up.  However, if you take the example of a wooded area, the rain of dead wood that falls from the trees throughout the year would build up to very noticeable levels if there was no decomposition.  It is also said that the soil fertility under temperate woodland is extremely high.  Now why is that?

Only the woody shreddings have been imported into the allotment.  The rest is a recycling of what is already here.  None of this has cost any money at all.  Nutrients that are in the composted material will be retained and not taken off the allotment to be put into green bins or council waste sites.  It will not be burnt so that nutrients are lost due to being changed into gaseous oxides.  Once it has broken down more completely and makes a black or very dark brown compost which can easily be sieved, it will be either used as a mulch or dug into the top soil of the allotment. 

I do import animal manures to put into the top soil but there are resources on the allotment already that I want to use.  These waste products from the allotment itself are the ones that I want to utilise rather than expensive imports.  I cannot, even if I wanted to, justify importing very expensive manures and fertilisers every year. I originally started allotmenteering to see how much food I could produce with as little expense as possible.  I must admit that during the following years I tended to rely more and more on imported nutrients.  However, now I am going to go back to my original idea of growing with the least input from outside the allotment as possible. 

A further reason for making the small ditches alongside the hard surface trackway is that the swale can be filled with stones.  One of the main contributors to the weathering of stones and smaller soil mineral particles are the mychorrhizal fungi.  Saprophytic fungi may also have a role if there is enough organic matter in the soil.  Fungal hyphae grow around mineral particles and stones and slowly decompose them using strong acids secreted from their tips.  These acids include oxalic, malic, citric and carbonic acids.   Nutrients from the stones are dissolved by these acids and pass into the soil solution so that they can be used by both plants and fungi. 

It could be said that this was a very slow process - and it probably is however, where else do the mychorrhizal fungi get their nutrients from?  They may forage for  nutrients dissolved in the soil solution but they would have to compete for these with the rest of the soil population.  The weathering of nutrients from soil particles seems to be a niche which fungi are uniquely adapted to exploit.  As to the small amount of nutrients that may result, plants and fungi need very tiny amounts of these elements.  The fact that they do break them down and that there are enough nutrients in the soil to sustain plant and fungal life, although never enough, means that these nutrients are being replenished and not just being leached away in the ground water. 

There has been some speculation about the presence of glomalin in the soil.  This protein seems to be associated with the cell walls of fungi.  Originally it was thought that fungi secrete this protein but it did not seem to have any benefit.  Associated with the cell wall of the fungi it may be a method of tightly binding the hyphae to soil particles.  It could be a sticky agent that allows fungal hyphae to attach themselves to stones in order to produce a more intimate association in order to dissolve minerals using secreted acids.  This would then explain why glomalin has been so  closely associated with formation of soil aggregates that are water stable.  These soil aggregates are very important in the dynamics of mass water flow and the recycling organic matter. 
Stones sieved out of the growing area top soil and added to the mini ditch. 

So while it can be quite irritating to have excessive large stones littering the growing area, maybe they should not be thrown away but used somewhere that mychorrhizal fungi can reach and weather down to produce nutrients for the rest of the allotment.  What fascinated me was watching gardeners carefully remove stones from their growing areas and taking them away only to replace them with rock dust.  Admittedly, rock dust will weather much more quickly than stone but they are more or less made out of the same thing.   I would suggest that the stone that I have put in the ditches has a greater variety of minerals than those in the bag of rock dust.  Something we have to thank the glaciers of the ice age for. 

Apart from capturing hard surface water run off from the trackway, slowing it down and spreading it out so that it can soak in slowly, maybe the stone filled ditches will increase the total nutrient content of the allotment by using the mychorrhizal fungi planted under the laburnum trees espaliered alongside the path.  These fungi will have unfettered access to the stones in the mini ditches, moreover the nutrients produced will be able to flow down the allotment because of the gentle slope towards the south.