Tuesday, 28 February 2012

Hardening off the sweet peas

It might be a little early but I put out the sweet peas to harden off.  If there is a frost then I will bring them in again.  I also put out the shallots.  I need the room in the greenhouse to plant the early peas.  I will continue to plant the peas in sectioned trays, as I did successfully last year, and keep them in the greenhouse away from the mice and the pigeons.

I do not have room to put the peas in yet and I have not put up the sweet pea supports.  They are fine in their pots at the moment but I would not like to keep them like this any longer than the middle of March.

I have a lot of vegetables to prick out now.  I have started but not finished pricking out the tomatoes and leeks. There are also some cabbages, cauliflowers, lettuce and onions that are ready to be put into sectioned trays.

The Apium graveolens rapaceum and the Apium graveolens dulce have not germinated yet.  I am keeping them in the warm until they do.

I bought some New Horizons general growing medium, lime, mychorrhizal fungi, chicken manure and seeds.  I should have a fairly full allotment this year.

Sunday, 26 February 2012

Digging the bean trench.

The only reason I am triple digging the climbing French bean bed is because I have some brushwood from the hedge alongside my allotment.  I have cut the hedge right back beyond the fence so that more light can get onto the allotment.  There is also a 30ft x Cupressocyparis leylandii  beginning to grow through the fence.  I will be cutting this back as far as I can.

The woody branches are being put on top of some pernicious weeds given to me by one of the top allotments. The weeds were put at the bottom of the trench.  Leaves and turfs are being put atop that.  The subsoil and the top soil are being sieved back into the trench with additions of pigeon and horse manure.

This process produces some really good looking soil.

I decided to take the Takesumi bamboo charcoal to the allotment so that I could marinade it in comfrey liquid.   I am wondering if I can apply this to the ground using the watering can.  It is very fine dust and will easily pass through the rose holes.  It can mash a bit in the tubs for a while until I need to use it.  

Took up six of the Brussel sprouts plants to take home.  Then I gave two to Chris, one to Mike and Mr Singh took some off one or two plants.  Even with all of this I have four plants still left in the ground.  

I think that I may  water the winter cauliflowers, leeks, strawberries, blackcurrants, raspberries, rhubarb and gooseberries with comfrey liquid.  This will give them a good start at the beginning of the season.  

Tuesday, 21 February 2012

Broad beans

I sowed two pans of saved broad bean seeds.  I am altering the planning in the bean and pea bed a little so that I can plant in sequence.  The beans will go in next to the supports for the climbing French beans.  I have started to put up the climbing French bean supports already, although I still need to finish the double digging in this area.

I also sowed Lathyrus latifolius, perennial sweet peas.  I have never grown these before so it will be a new adventure.

The celery and celeriac have not germinated yet.  They take a lot longer than the tomato seeds.

Saturday, 18 February 2012

Tomato seedlings are through.

I took the seeds out of the airing cupboard today and all of the tomatoes Lycopersicum esculentum  have germinated.  I put the pots into the cool greenhouse to grow on.  I will prick them out into their own pots when they are a little bigger.  The other tomatoes are doing well in the greenhouse.

None of the other seed I sowed has germinated yet.  I will have my work cut out when they do.

Went down to the allotment this morning and continued with the hugelkultur bed until it started to rain.  I put the weed turfs at the bottom of the trench this time because there may be some bind weed tucked away in it.  This was covered with a layer of holly branches, leaves and turfs.  It will give me a good raised bed to grow the climbing French beans on.

Friday, 17 February 2012

Doing some more Hugelkultur

I wanted to bury the old blackcurrant bushes and the cuttings with big bud on them.  There were some other things that needed burying so I decided to do some trenching.
One spit down.
I am going to put the climbing French beans here so a good deep root run will be good for them.  The top soil is left on the right of the picture.
Now we go down another spit.
The old huglekulture wood can be seen.
When I dug out the second spit, I found last years hugelkultur wood.  It had rotted away to a fibrous peaty mass. I am going to mix this with the subsoil when I put the soil back in the trench.
Having a layer of woody material under the Brussel sprouts does not seem to have affected them detrimentally.  In fact I think that it might have encouraged them to grow larger.
I used the fork to turn over the bottom of the trench.  You can see the sandy clay that is the subsoil on the allotment.  I don't usually turn this up because the top soil is so deep on the allotment.  This area used to be where my old greenhouse was and I never double dug here while the green house was up.  This means that the top soil is not very deep.
I put the old blackcurrant bushes at the bottom and then got some more brush wood.  These are twigs and branches from a laburnum tree overhanging the fence.  Laburnum is a legume nitrogen fixing plant. Does this mean that I am adding extra nitrogen to the soil?
I then added a good layer of weeds that included couch grass and docks.  They may grow but I don't think so. On top of them I put a thick layer of leaves.  I'm not too sure about these leaves.  They have been rotting away in the bins by the gate for a while but they still look a little ropey.
Still needs must... Finally I put a layer of upturned turfs on the top.
If the weeds can grow through that lot then they deserve to be given a chance.  They wont be though.  Now I put the subsoil back but I am going to sieve it and add horse and pigeon muck.
The subsoil looks much better when it is sieved and mixed with manure. I am sieving through an old bread tray.  The holes in the bottom of the tray are about 1 inch square.  I just push the soil backwards and forwards in the tray until it falls through the holes.   I will sieve the top soil on top of the  subsoil mixing in more horse and pigeon muck.

And that is how I do hugelkultur.  I am hoping that this will heat up a bit and allow me to get an early crop of lettuce off it.

Allotment photographs for February 2012

I remembered to take my camera and take some photographs today.  It is a bit over half way through February. Allotments do not look good at the best of times and this is not the best of times. They are honest photographs of a hard working allotment warts and all.
Worm bin
The worm bin has been very useful recently because I have been putting dandelions, bind weed and mare's tail in it for the worms to get their teeth into.  It is producing quite a bit of liquid which I drain off using the tap at the bottom.  I am just mixing worm bin liquid with the comfrey liquid at the moment.  The nettles have died right back but I am sure that they will start shooting in a couple of weeks.  I will put them with the comfrey and sweet cicely to rot down in the big green bins and make some lovely liquid manure. I am going to take down one of the compost bins because I never fill them.  The one behind the worm bin is going to go.  It had the pigeon muck in it so the ground will be quite fertile.  As it has so many stones in it, I will leave it to the nettles to colonise.  I will use the nettles to make nettle liquid fertiliser.

 I will fix up that bird table when I get a chance.

Comfrey bed in January
Dug over in February.

It does not look like it but I have dug over the comfrey.  Got rid of those stones thank heavens.  The comfrey died right back when the cold weather came during the beginning of February.  I have put the sundial up but I am not sure whether I am going to keep it here.  
Seived new potato bed soil.
Finally finished sieving this soil at the end of January.  I have taken a lot of cuttings from the gooseberry.  Some of the autumn cuttings have rooted all ready.  The black bins at the back of the bed are over the rhubarb to force it.  I have put some horse manure around the bases to try and warm the soil and speed the process up.  I doubt if I will have any manure left over but if I do I will put it around the rhubarb.  
This is all the manure I have left
I am going to put oca alongside the trackway and 90 degrees to the path.  It is very open here and they will get the light all day.  Update in March - only if you buy some more Tone because all the tubers were killed by a heavy frost.  
Poor old vine
I have moved this vine so many times that I am really surprised that it is still going.  It is in the poorest ground on the allotment. Vines are put into poor ground to restrict their prodigious growth during the summer and to encourage fruiting.  When it was growing strongly, I had to cut it back about three times a year.  I have built up the soil quite a bit by adding dead organic matter.  To keep this good soil away from the vine, I put the slabs around.  It meant that I did not need to move the vine again..  I reckon that lots of nutrients will get to the roots because the slabs do not keep enough of the poorest soil around it but nothing I can do about that except continue to cut it hard back in summer.   I decided to use the stone that I have been sieving out to make a stone mulch for it.  
Rhubarb under the forcing bins
A good sieved soil for the potatoes
This soil still looks a bit ropey but I reckon that it will grow some good potatoes and oca Oxalis tuberosum.  You can see the stone that I removed in the background.  

The new onion bed is full of green manure, garlic, American land cress, rocket, broad beans and tulips.   

The garlic got knocked about a bit by the frosts and snow but it grows much better when it has been frosted like this.  
Raspberry canes
Raspberries are doing all right.  They usually get broken by the wind but I have tied them in very carefully this year.  
New sweet pea bed.
The new sweet pea bed is nearly empty now.  I have dug in some horse manure and leaves.  It has been rough raked and will need another rake before I put the poles in.  There are still some leeks and celeriac to be eaten.  
Leeks under enviromesh
New brassica bed.
I have a flower garden here.  All the bits and pieces have either been given to me, come from cuttings or grown from seed.  The old plum stump might come in handy because I want to do some bud grafting onto it. 
Green manures in brassica bed
The green manures were planted a little late and have not developed very well.  I will leave them in until the brassicas are ready to go in.  
No sign of big bud on the blackcurrants but I have cut them so hard back that I don't think I will have much of a crop this year.  
Strawberry bed.
The strawberries are getting a little overwhelmed with the poached egg plant seedlings.  I will take the poached egg plants out soon but use them elsewhere in the allotment as a green manure or companion plant. The purple sprouting broccoli has not flowered again.  I will only plant one small row this year.  
Winter cauliflowers
I still have quite a few winter cauliflowers.  They will come in April and I am hoping they are out of the way when I want to plant my late peas.  
More of the winter cauliflowers
I have decided to put in a huglekulture bed where the Brussel sprouts are being taken out.  I am burying the old big bud infected blackcurrant bushes and other stuff I have found round the allotment.
Been eating Brussels since before Christmas
And I still have these left.  They will be eaten in the next few weeks though.  They grew quite large this year. They are about 3 foot tall.  

I have sieved this soil in readiness for the carrots.  There should be an unimpeded root run for them.  The bay tree is well and truly wrapped up.  I did not want it to die back this year.  
Green manure on roots bed
Celery and leaves bed
I have dug and sieved horse manure and pigeon muck into this area for the "leaves".  I will be planting Swiss  chard, celery, celeriac, lettuce, etc. where the tarpaulin is.  I have put about ten beer traps under the tarp to try to reduce the number of slugs and snails here.  It is the first time for a great number of years that I have tried celery.  It is usually spoilt by slugs before it can be eaten.  I am going to use nematodes over this bed later in the spring in order to reduce their numbers.  

Taking cuttings of house plants.

I am not a very good house plant person.  I tend to forget to water and supply them with nutrients.  However, I do enjoy taking cuttings and producing lots of plants from individuals.  To all those that do not like cloning switch off now because taking cuttings is cloning plants.

A great many different greenhouse plants can be propagated using different types of leaf cuttings.  I usually take one complete healthy leaf off the plant with the petiole still attached.  The petiole is then pushed into the cutting compost - I still like to use New Horizons peatless compost and sharp sand in a 3:1 ratio but  I am using a 3:1 compost to perlite in the photographs.  The leaf stalk is pushed into the compost until the leaf lamina is lying on the compost surface.

Taking a leaf cutting from a Saintpaulia
It is remarkable how easily these cuttings produce new plants.  In a relatively short time roots are developed at the base of the leaf and the new plant sends out shoots.  Both Gloxinias and Saintpaulias are ideal subjects for taking cuttings.

A different method is used when taking cuttings of Begonia Rex.  A healthy leaf is taken off as I did with the Saintpaulia.
Taking a cutting from the Begonia Rex
The petiole is removed, although I have often left a stub of petiole on the leaf and pushed this into the growing media.  
Then the veins of the underside of the leaf are scored with the knife although I have had success with horizontal cuts across the veins as well. 
Scoring along the veins on the back of the leaf.
The leaves are then placed onto the growing medium and weighed down with stones to provide a good contact with the soil.  
Leaf lamina cuttings on the growing media
In some books it is suggested that wire is used to peg down the leaves.  This damages the leaves and allows a possible entry point for pathogenic fungi so I avoid using it.  

Begoinia Rex can also be propagated using leaf sections.  

Taking leaf sections
The main requirement for this method of taking cuttings is that the leaf is placed vertically in the growing medium the right way round.  The tip of the leaf or the part of the leaf cutting that would be nearest the tip of the leaf should be pointing up.
Sansevierias (Mother in law's tongue) can be propagated like this as well.  They do not grow to type though because they are chimeras.The veins going from thick at the bottom to thinner at the top. 
Sansevierias (Mother in law's tongue) can be propagated like this as well.  They do not grow to type though because they are chimeras.

Leaf cuttings need to be rooted in a warm, damp atmosphere so it is essential to keep everything used in the propagating procedure as clean as possible; compost and containers being sterilized if necessary.  It is also important to get the right balance with watering because provide too much and the leaves will rot, while too little  will dry them up. Most of these cuttings will need a temperature of about 16oC to 18oC  to root well.  If they can be put into a heated propagator this will increase success.  

Thursday, 16 February 2012

More seed planted.

I put in the rest of the Lycopersicum esculentum seed.  They are tucked away in an airing cupboard to give them a little more warmth.  They should be through in about a week or so.  I planted some more celery Apium graveolens var. dulce; lettuce Lactuca sativa; Cabbage Brassica oleracea capitata "Golden Acre".  The Celeriac Apium graveolens rapaceum were sown in a small pot and put in the airing cupboard with the tomatoes.

I have pricked out onions, celery, cauliflower and cabbage into trays or pots using the New Horizon's general purpose compost.  I have put all of these onto the shelves inside the polythene "greenhouse" I have put into the big greenhouse.  Not only will this keep them a little more protected from frost but will bring them on a little.

I went down the allotment yesterday and continued to tidy the comfrey bed.  I don't know if I have straightened all the lines of comfrey because they have died back and I could not find all of the plants.  They are more or less straight now though.  I have constructed the sundial here as well.

I put some black dustbins over the rhubarb, Rheum rhaponticum,  to force it a little.  This will mean that we can get some good petioles at the end of March and the beginning of April.  The skill is to remove the bins before the rhubarb becomes too weakened.  I heaped some of the horse muck around the bottom of the bins to heat them up and bring the rhubarb on a little quicker.

I have taken out the black currant cuttings because they have some big bud on them.  I think that the severe pruning I did on the main bushes has cleared off the big bud,  Cecidophyopsis ribis, from them. They look quite healthy.  I replaced two that died over the winter with cuttings that I had potted up.  I think that I am going to bury the plants that I took out.

I wasn't going to dig this area over; just hoe and use the three pronged cultivator to rake it over.  However if I am going to bury these blackcurrant bushes, I might as well dig the rest over as well.  I will have to bury the blackcurrants quite deep to avoid them depleting the soil of nitrogen and to prevent the big bud mite from escaping into the top soil.

I have started in earnest on the celery bed.  I dug out a trench and then sieved horse manure and pigeon muck into the next spit down.  I dug up the remains of the beans and peas that I had dug into this bed but they broke down and sieved into the soil just as the manure did.  There are some plane tree leaves Platanus x hispanica which are a little thick and rubbery in the horse muck.  I didn't think that they would go through the sieve but they did and you cannot make them out now because they are mixed in so well with the soil.  I am trying to keep this trench lower than the surrounding soil so that I can keep the celery damp throughout the year.  

We may have major problems with drought this summer because they are saying that the water table is very low now.  I hope that I have added enough organic matter to take up any rain water that we get and provide a reservoir which the plants can tap into.  I am going to try to use mychorrhizal fungi on all the plants that form associations with it because this may help in lessening the effect of drought.   

Sunday, 12 February 2012

Improving the soil

Undoubtedly, soil preparation and improvement is a major part of success in the vegetable garden. In one of my lectures I said that it took about 1000 years to produce 20mm of soil.  As I didn't qualify this, I got several gardening student questioning me afterwards.  By adding dead organic matter to the soil and artificially weathering it by digging or rotavating, we can of course increase the amount of top soil available for cultivation.

What I should have said in the lecture was that it takes about 1000 years to produce 20mm of soil naturally.  Anthropogenic soil improvement by adding amendments will change the soil relatively quickly, although my soil is only just becoming beautifully friable and highly productive after thirty years of adding organic matter.  I would never suggest that pedogenesis is an easy or quick process that can happen over night but there are things that gardeners can do to improve the soil for cultivation of vegetables and flowers.

One of the more insipid practices is building raised beds and then filling them with commercial bagged "compost".  This material is neither compost nor soil.  It is usually made from sterile materials such as peat,  perlite and vermiculite.  The reason that it grows vegetables relatively well is because there are few pests in the growing medium.  The problem is; there is few of anything living in the growing medium.

This is problematic because there is nothing in the soil to recycle nutrients -there is little bacteria, fungi or invertebrate life.  Without this background base level, living fraction of the soil, fertility cannot be maintained. There is little to prevent the leaching of nutrients out of the soil and if a no dig system is used as well then there is no turning up of nutrients from lower in the soil profile.  It is saprophytic organisms that change dead organic matter into substances that plants can use.  We call these chemicals plant soil nutrients.  They are listed as nitrogen, phosphorus, potassium etc., although they are never taken into the plant as elements.  You can bypass the saprophytes by adding just the inorganic chemicals themselves but this leads to two major problems and many minor ones.

In order for the plant to take in these nutrients they must be soluble in water.  This means that they are relatively easily leached from the soil.  Inorganic fertilisers have been indiscriminately applied to soils and disrupted many ecosystems due to leaching into water courses and the sea.  Secondly, they remove the need for addition of organic matter to the soil which leads to depletion of  saprophytic organisms and inhibits nutrient sustainability.  Adding organic matter, where nutrients are locked into molecules that need to be broken down by saprophytes, produces a long term sustainable process of soil fertility improvement.  It is a slow acting decomposition which does not saturate the soil with leachable nutrient.  What goes in the soil stays in the soil unless it is taken up by plants.

The adding of dead organic matter to the soil also has a number of other benefits that add to the fertility of the soil.  Plants respire as well as photosynthesise.  This means that they take in oxygen as well as carbon dioxide.  As the roots are below the soil they do not have access to light and cannot photosynthesise.  Yet they do respire and need a supply of oxygen from the soil.  Dead organic matter can increase the amount of oxygen that can penetrate the soil by providing air spaces and keeping the soil "open".  In a similar way organic matter can provide a route through the soil for water increasing drainage to avoid water-logging.  As organic matter absorbs water it also provides a reservoir that buffers water-logging and drought. Organic matter and clay are the hooks that enable nutrients to remain in the soil and available to plant roots and mychorrhizal hyphae.

Mychorrhizal saprophytic fungi form symbiotic associations with plant roots which allows nutrients that are produced by fungal breakdown of dead organic matter to be transported to the plant.  There is some suggestion that these networks of fungal hyphae connect plants with each other allowing the flow of nutrients and photosynthesis products to move to plants that are compromised because they are in shady or nutrient poor environments.  Science is still trying to uncover the complexities of this soil interaction that relies on the addition of dead organic matter.

I would suggest that  my soil is more productive now than it was when I took the allotment on over thirty years ago. A lot of nutrients have been taken off the allotment in the form of vegetables, eaten and disposed of down the sewage system. The reason why it is even more fertile now is due to the addition of dead organic matter in its many forms.  It would never have occurred to me to use growing medium to improve my top soil when I started gardening. Indeed I would have avoided peat because I saw it as an acid medium.    A good load of cow muck was about all that was needed.  I doubt if I could have increased the fertility as much by adding peat based growing mediums even though they are infused with inorganic fertilisers.

So what dead organic matter can be added to the soil?  The word organic in this context means that which was once alive. (In chemistry it refers to any molecule with carbon in it)  You can use any organic matter to produce good soil.  There are many lists circulating around the gardening forums.  I don't know whether they are accurate or not in their N:P:K ratios but that is beside the point.  They give a list of things that you can add to the soil or compost heap and that will decompose to give plants nutrients.

For example:  http://idigmygarden.com/forums/showthread.php?t=17366

I would suggest that adding any dead organic matter to soil will benefit it.  To support this assertion, I would site the evidence that ancient human settlements can be identified by high phosphate and charcoal levels in the soil.  This leads to lush growth of plants that has been maintained over many centuries.  I doubt if ancient human civilisations were as selective of the organic matter they buried as modern man is. The self sustaining properties of Terra Preta soils are probably due to an indiscriminate addition of dead organic matter together with charcoal.

There is some organic matter that is more equal than others, though.  Seaweed contains a lot of nutrients - particularly potassium and is a valuable amendment to soil.  We send so much of our nutrients down the sewers and eventually into the sea that using seaweed seems to close the cycle so that these nutrients can be returned to the soil.  Care must be taken not to add too much sodium chloride though.

There is a suggestion that adding undecomposed organic material could be detrimental to the soil.  This is because micro organisms need nitrogen and forage for this in the soil when they are decomposing organic matter.  Well what goes around comes around.  These organisms will die themselves and decompose in the soil and provide nutrients.  If you are continually adding organic matter into your soil, as it becomes available, as  I am then the cycle of decomposition and growth develops into a dynamic equilibrium where the level of nutrient in the soil matches the amount being used by living things preventing leaching and locking the nutrients into a sustainable cycle.

However, it may well be worth composting organic matter to allow saprophytes to break open the cells and decompose the large organic molecules before adding it to the soil.

The more that I compost the greater my despondency  grows.  We import so much organic matter from other parts of the world, sucking out their nutrients most of which we dispose of down sewers and on land fill sites.  Even composted they are a testament to our exploitation of other ecosystems.  This cannot be sustainable.

One of the major inputs of nutrients into soil must be bird droppings. You can judge the amount of bird droppings that cover the land if you look at house roofs.  They are usually covered in little circles of algae where a bird dropping has landed.   As this has been happening for millions of years there have got to be soil organisms that exploit this nutrient throughout the world.  Many soil organisms like bacteria and fungi produce enzymes that they secrete into the soil that break down organic substances so that they can be absorbed through their cell walls.  These enzymes themselves will be broken down but until they are they will continue to work; providing nutrients for other organisms within the soil.  I would suggest that this is why chicken manure breaks down so quickly and produces such good results when growing vegetables.  Similarly other animals have been weeing over the soil for similar amounts of time producing a situation where the enzyme urease is ubiquitous in the soil.  The enzyme's interaction with clay and humus means that it is relatively long lived in the soil and is a good source of ammonium ions.    Urine breaks down very quickly in the soil and should be a major amendment rather than just flushed into sewers.

One of the major constituents of soil is the mineral content that is derived from weathered base rocks.  It is also the major source of naturally acquired phosphate and potassium nutrients.  I would suggest that cultivation of the soil is another way of weathering the soil.  Continual turning of the soil leads to break up of stone due to frictional forces.  Grinding in this way allows the production of rock dust with large surface area that is more susceptible to attack by humic acids. Release of nutrients in this way will increase the fertility of the soil.    Does this mean that we should add rock dust to soils to enhance this process?  I don't know but I would like to check it out.

To all those that think that adding undecomposed organic matter to soil will lower the nitrogen level in the soil; what about green manures?  A green manure is one that grows quickly and then when dug into the soil will decompose quickly. The speed of decomposition is really the key because nitrogen will be released by dying micro organisms after decomposition.  I just think that any dead organic matter that will decompose quickly could be dug in in a similar way.  Also there are a wide range of plants that can be used as green manure with different ones giving potentially giving a range of benefits.  I am starting to wonder if a more effective and cheaper choice would be to allow a covering of annual and ephemeral weeds and then digging in before they seed.  Yes, something we have all been doing for years.  I can understand the arguments against this.  Ephemerals, like groundsel (Senecio vulgaris ) are quick to flower and seed even in the winter and can easily overwhelm a vegetable bed.  However, if a careful watch is taken of the development of these weeds and you have time to dig them in before they seed then they will make as good a green manure as annual meadow grass.

Green manures can also add nitrogen to the soil.  If they are members of the legume family then they are probably associated with nitrogen fixing bacteria which takes nitrogen from the air and uses it to produce proteins within the bacteria cell allowing excess to be passed to the plant.  When the whole plant is dug into the soil it will decompose releasing this nitrogen in a form that other plants can use.  This is something that I do with cultivated peas, sweet peas and beans as part of a rotation scheme.  I would suggest that addition of nitrogen using both cultivated legumes and such things as winter tares and clover are an ideal way to introduce a slow acting and sustainable nitrogen source to the soil.   

An intimate knowledge of soil structure and texture is not really required in order to be a good grower.  All you need is a bit of common sense.  The soil texture is the percentage of sand, silt and clay in the soil and this cannot be changed easily.  The soil structure is how these particles are arranged into aggregates. Both humus and calcium are implicit in the formation of sol aggregates.  This demonstrates how organic matter, as it breaks down, affects the friabability of the soil.  Calcium helps to flocculate - clump together-  clay minerals in the soil and allow the soil to become more open.  I have a soil with a high percentage of sand which produces a very open soil prone to drought and leaching.  I add a lot of organic matter to ameliorate both of these problems.

Around soil particles is usually a film of water containing humus in one form or another.  Although there is evidence that this fraction of the soil is relatively long lasting, addition of amendments such as comfrey, nettle and sweet cicely liquid together with worm bin liquid cannot but add to the soil humus content.  These liquids seem to be broken down relatively quickly and nutrients locked up in them made available to plants within days or weeks of application.   One application of these liquid manure lasted a whole season on the roots bed.  I just watered a relatively weak solution/suspension of comfrey along the seed drill before sowing seed.   I must admit that I use this liquid manure mix all the time on the allotment and it seems particularly good for tomatoes Lycopersicum esculentum and sweet peas Lathyrus odoratus

I have been experimenting with the use of charcoal as a soil amendment with some success.  Although I was sceptical initially because charcoal had been reported as reducing the fertility of the soil, I did start applying it  in planting holes of vegetable plants.

My reasoning was that charcoal reduced soil fertility by adsorbing or absorbing plant nutrients.  Charcoal has a capacity to do this with a wide range of compounds.  If charcoal had this characteristic when added to soil, why not provide the nutrients before adding the charcoal to the soil.  I decided to submerge the charcoal in a dustbin of comfrey liquid manure and let it marinade for as long as possible before adding to the soil.  Thus the charcoal will become saturated with nutrients and not remove them from the soil.  However, when plants, bacteria or fungi remove nutrients, as is their want, nutrient will defuse from the charcoal into a depleted soil. In addition, when excess nutrients are added they may be taken up by the charcoal preventing leaching and providing the soil with a buffering effect.  With indications that charcoal is a particularly long lasting amendment to soil this buffering could produce a sustainable nutrient system that enhances soil fertility greatly.

After experimenting with different sized lumps of charcoal, it would seem that the very fine dust like particles are the most effective in providing nutrients to the soil.  Rather than crushing  lump charcoal as I have been doing up until now, I am going to use the Takesumi bamboo charcoal which is very fine and has an enormous  surface area for adsorption and absorption.

There is also some evidence that charcoal produces a protective micro habitat that could be exploited by bacteria and fungi.  If mychorrhizal fungi is added to the charcoal before it is used in the planting holes then this might help the mychorrhiza to establish and give it a source of nutrients that can be transported to the roots of vegetables.  Now further evidence suggest that EMs (essential micro organisms) which consist mainly of bacteria can also be used to enhance the growth of plants.  Remarkably, it is now being promoted commercially...


The more I sieve the soil the more I am convinced that sieving is a good choice.  Mixing the soil to make a more homologous blend of material equally accessible to all plants seems to be an eminently sensible thing to do.  Having pockets of high nutrient concentration leads to plant damage because water is drawn out of the plant root and into the soil.  High nutrient salt concentrations are bad for the plant.  Isn't this another argument for the use of organic manures that decompose slowly; limiting the concentration of soil water nutrient salts?  Sieving just adds to the diluting effect; spreading and mixing organic manures throughout the soil.

The worry I have about using the lasagne method in raised beds is that there seems to be little mixing of layers. This will give relatively high concentrations of nutrients in some parts of the profile while others have very little.  Also, it seems like an awful lot of effort to achieve what a are dubious results.  Such careful separation of vegetable bed from the natural soil seems perverse to me.  To produce a viable soil with this method particularly if it is no dig you would need worms to mix the various layers of the lasagne.  Most of the procedures start with an impenetrable layer of plastic, cardboard and newspaper.  Only the most persistent of worms would get through that.

While I decry this layering method of gardening there are other procedures that seem to be a little more reasonable if done properly.  Huglekulture is where logs, branches and brushwood are used to make a raised bed.  I would suggest that these should be buried away from the top 300mm of the soil profile.  Trenching and bastard digging allow very high carbon content material to be added to the soil with some success.  I like big deep trenches because you can get rid of a lot of unwanted organic material.  It also means that you can get rid of some of the more pernicious of the weeds.  While Elymus repens and Urtica Dioica can be disposed of in this way, mares tail Equisetum arvense and bindweed Convolvulus arvensis must be put into the worm bin because they will survive burial.

The logs, branches and brushwood rots down to a very friable compost after two or three years and this can be incorporated into the top soil.  While it is rotting down it is forming a sponge like layer that allows water to pass through for drainage keeping some water as a reservoir for drier periods.

Rather than burying high carbon material, it can be shredded and put on top of the soil as a mulch.  I am not sure whether mulches improve the soil but they do seem to retain moisture. I think that they cause more problems than they cure.  My major concern is the way they attract slugs and snails.  I would not put a mulch onto a vegetable bed until the plants are very mature.  I would rather be able to get between my plants with a hoe.

Another way of making an open friable soil particularly when there is a high proportion of clay is to use gravel.  I have used it several times and in conjunction with compost and manure it works very well.

So do we need to dig or not?  I would say that in order to mix the soil and make it homogeneous digging is unavoidable.  It can be used to incorporate organic matter into the soil and maintain a sustainable fertility.   Digging maintains the soil structure and allows free drainage.  It buries weeds and helps to prepare a good tilth for seed sowing.  And what is more; even the very most enthusiastic no digger will dig to harvest roots and potatoes. They will also dig in green manure.   In order to avoid killing worms, I avoid digging where I do not need to, however I am not going to be religious about it and get all guilty when I do dig.  I just do what works for me...

Thursday, 9 February 2012

Seed potatoes have come.

The seed potatoes from JBA came on Tuesday. www.jbaseedpotatoes.co.uk  I am keeping them in the house at the moment because it is too cold  to put them into the greenhouse.  They are of a good size for seed potatoes.  I have only got Kestrel this year because I grew too many last year.  If I stick to my plan and just plant these, I should have more than enough.

I will chit these potatoes by putting them into trays and leaving them on the staging in the cool greenhouse.  This will help them to develop small buds.  It is suggested that this encourages the potato to produce more or bigger tubers.  (Tubers are stem swellings at the end of rhizomes.  You can tell that the tubers are stems because roots do not usually have buds on them.)  I don' t know if chitting makes any difference to the yield of potatoes but I think that reducing the number of buds will give larger tubers.

I am not going to take any of the buds off.  I will grow them as they come.  I hope that I get as bigger yield as I did last year.

I am going to wait until after the cold weather to plant any more seed.  The ones that I have are growing well still but they are getting a little drawn because I cannot put them out into the greenhouse yet without them getting damaged by the cold.

The sweet peas seem to be surviving at the moment.  They have been knocked about by the cold weather and they need to be watered.  I cannot water them at the moment so I will have to wait until it warms up a little.  Watering now may lead to the water freezing on the plants which is not a good idea.  Also it encourages fungal damping off.

This cold weather is not good for gardeners.  You cannot get onto the allotment or garden to do any jobs.  Having said that I may go to the allotment today to get some more vegetables.  I want to get the rest of the carrots, some parsnips, beetroot, salsify, scorzonera, Brussel sprouts, rocket and American land cress.

One of the worst jobs in gardening is harvesting Brussel sprouts in this cold weather.