Thursday 22 September 2011

Coming to an end of the triple digging.

I've got to the last trench of the triple digging and I am filling the bottom with oak branches, compost and old turfs.  This is a kind of huglekulture, however they delivered some pigeon muck today and I used some on top of the branches.

Now here is the theory.  Bacteria and fungi that will break down the oak branches need nitrogen to do this.  The bacteria and fungi's carbon source will be the branches, compost and turfs.  The nitrogen source will be the pigeon manure.  This should mean that the branches will decompose quickly into friable organic matter that is easy to incorporate into the soil next year.  Adding the pigeon manure may prevent the fungi decomposing the buried organic matter from depleting the soil of nitrogen.  This often happens when woody material is added to top soil.

Here we need a note of caution.  Pigeon manure is very powerful stuff.  It has a NPK of 5:2:1 but I think that the nitrogen ratio may be higher from the smell of ammonia coming off it today.  I have put most of the pigeon muck in one of the compost bays that I have just emptied.  I got about 18 bags of it all told.  I will be using it but in the same way as I would use chicken pellets.  I will put a top dressing on the surface of the soil when I begin planting and then hoe it in.  I will not be using great shovels full of the stuff.  It is serious manure.

I once dug in neat, new pigeon muck into one of the beds and then planted beetroot on top.  Nothing grew where the pigeon muck was dug in but I had big beetroot where there was no pigeon manure.

There were a few potatoes that I had missed in the potato bed but not too many.  I doubt if I have found all the tubers but I can live with just a few coming up in the onion bed next year.

I have been giving the top soil and the subsoil a good mixing separately to make sure that last years compost is distributed throughout the soil profile.  The soil was very dry so it was quite easy to do.  I like to make conical mounds of soil and put spade fulls on the point at the top.  This means that each of the spade fulls falls down the sides of the cone and you get a thorough mixing.  I have been careful to keep the top and subsoil apart so that there will be little mixing between the two.  I don't think that a little mixing is harmful but it is best to keep them apart.  The subsoil does not contain the amount of organic matter as the top soil although I am attempting to remedy this.  Also the subsoil is much lighter in colour than the top soil because it has not been dyed black by the humin together with the fulvic and humic acids derived from decomposed organic matter.

There are many reasons for digging but the one that has interested me recently is the suggestion that digging enhances weathering of the mineral part of the soil.  The mineral part of the soil is a primary source of soil potassium and phosphorus.  The idea is to increase the breaking up of particles so that these major nutrients can be released in a form that can be taken up either by mychorrhizal fungi or the roots of plants.  Mixing the soil with compost, which is breaking down into humic and fulvic acids and humin, also aids in this process because these compounds react with (chelate) mineral elements of the soil.  What we are doing is making previously inaccessible minerals locked up in stones or mineral fragments relatively soluble and available to plant roots.

This is why digging whether single, double or triple is a good way of improving the fertility of the soil.  So with the additional benefits of improving drainage; adding carbon; adding nutrients ( in the form of manures, fertilisers and green manures); removing weeds; producing a good crumb and friable  structure to the soil; adding air to lower layers of the soil profile; deepening the depth of the A horizon (top soil) to improve the root environment; increasing the solubility of minerals by ion exchange; there seems to be very good advantages to digging.  I can understand the reasoning behind the no dig method of cultivation but there does not seem to be as many advantages as digging.

I will have a major job in levelling the potato bed because of all the triple digging and mixing I have done but I want to plant some seed so I will have to do it well.  In order to consolidate the soil, I will be treading on it systematically before raking.  Most seeds seem to like a firm soil to germinate in.  I will be taking short side steps along the planting line and then going over with the rake.  This will also break down any large lumps of soil so that the raking will be easier.  It may seem silly to spend so much time putting air into the soil only to squeeze it out by treading on it.  There is a need for a good equilibrium between the amount of air within the soil and the amount of water.  Too much air will restrict the amount of water that roots can obtain and this might lead to water stress.  Too much water will restrict oxygen necessary for root respiration.  Much less oxygen is available dissolved in water than there is in air.  The trick is to make sure there is enough of both.

I will be sowing rocket, lambs lettuce, spinach ( under cloches) chard, and a variety of green manures on the triple dug bed.  I also have four pots of broad beans to plant here as well.

Still cropping big time.  Some large carrots - shows you how effective the enviromesh is; big beetroot - I hope that they are not getting woody now; Hamburg parsley, salsify and scorzonera giving remarkably large roots and parsnips are growing well.  I like to leave the parsnips until the first frosts and with all the other vegetables that are cropping now I do not need to use them.  Pumpkins are coming well except that they are not very large.  Got some big swedes and they still taste really good.  Kohl rabbi is still growing well.  The peas have not grown very well.  I doubt if I will have any off them at all.  Still they will make good green manure.  This is the last time I plant late peas in the same area as the earlies.  The Borlotti beans have done well but they really need to be harvested and podded.  Too many runner beans again.

And too many blooming tomatoes this year.  There has been no blight and all the plants I put outside have fruited really well.  I have tomatoes coming out of my ears now I have eaten so many.   Everyone is trying to give me apples too.  There are just so many apples you can eat.  The Bramleys can be kept for a while so I might put them into the store shed.

I am attempting to clear out the store shed so that I can put the canes in.  I am not succeeding very well because for everything I take out and home there are about seven or eight things I need to store in there.

I took out the broad beans so that I had room to plant some more leeks.  I podded the beans and have left them in the store shed to dry so I have seed for next year.  They are drying on one of the shelves.

I will have enough room on the shelves for apples because all the onions had white rot and had to be thrown away otherwise I would be squeezing things in.  I have room for the squashes, pumpkins and apples but I will have to move the potatoes around.  It would be much better if I could store the canes outside somewhere.  That might be the solution.

I am cropping the comfrey and digging the fresh leaves in along the raspberry row.  The raspberries seem to benefit from a good dose of comfrey.  I will do this with the strawberries too.  I am moving them up to the brassicae bed and will water them in with a little comfrey liquid too.

Then it is mostly clearing for the winter.

No comments:

Post a Comment