Looking after our soil


 Our basic aim is to feed the soil and the plants will grow. We avoid using manufactured and chemical products wherever possible, preferring to using natural organic products to fertilise our soil and replace the nutrients that our harvest of fruit and vegetables takes from the soil. Our preferred materials are our own made compost from plant remains and horse manure.

Our soil is good but rather heavy and
very stony. We are trying to improve it
by adding more organic matter

The 11 compost bins. Notice how the different designs on the
side ensure that the planks are replaced in  the correct order.

A pile of weed prior
to being composted

Initially we used our own compost made from all our crop leaves, stems and roots that are not to be sold plus all the weeds growing on the plots. We mainly use cool composting which is a slower method of composting than hot composting, but does not require regular turning of the heap. Initially we added our plant and weed remains and then a layer of brown material such as leaf litter, torn up newspaper or cardboard, straw or wood chippings. This slow method of maturation at low temperatures means that a relatively low proportion of the carbon in the pile has been converted to carbon dioxide during the maturation process. Furthermore the final product should be high in fungal hyphae and mycorrhiza which will promote root growth when applied to the soil.

However a problem was experienced with this method of cool composting: sometimes some of the more persistent weed roots remained in the compost. So in 1915 the decision was taken to remove the roots of 5 pernicious weeds which grow in abundance in the fields: couch grass, bindweed nettles, docks and dandelions. These roots and any seeding parts were placed in a large woven plastic bag which was placed in  a barrel. When the bag was full of plants the barrel was filled with water so drowning the weeds and causing them to die and decay anaerobically. After about a month the weeds had died. When all the weeds were dead the bag was removed and the contents of the woven bag were composted. The liquid was used as a compost tea which was available for watering on the plants. Generally it was diluted to 1 in 5 of its original concentration.
We have 11 compost bins in which we make compost and 8 40 gallon drums for making liquid feed.

Green waste going in the bin

We also use manure which is obtained from local stables and has been thoroughly rotted generally for up to five years. We tend to purchase manure by the trailer or lorry load often buying as much as 60 tonnes for use on about 2.5 acres of land in a year. The cost is chiefly for the hire of the vehicle. Manure is generally spread on the fields in October after the summer crops have been harvested and

Mike our compost supervisor digging out mature compost

before the plot is covered with black plastic for the winter. The black plastic stops weeds growing and prevents leeching of nutrients through heavy winter rains. The worms pull the compost into the soil   during the winter.

Newly added compost to bin 11 and the 40 gallon drums

Four of the 40 gallon drums. Approximately one drum is
filled a month and then left for four months.

Notice explaining what to do with the pernicious weeds

We also have used Progrow,  Veolia Progrow is a soil conditioner produced by Hampshire County Council  (from green recycled waste which has been allowed to heat to high temperatures). It  has a structure that will break down heavy clay soils and add humus to light sandy soils.  Progrow looks like small charcoal like pieces (not actually called biochar) which are dry and fairly light. We have used it extensively to lighten the soils. However it has a pH of 8.4 and when mixed with our clay with chalky flints soil we find that the pH is generally between 7- 8 and thus too alkaline for the health of some fruit and vegetables which prefer the pH to be 5.5-6.5. Some crops did not seem happy growing at pH's above 7 and when we investigated we found that it was due to boron deficiency due to the high pH.  So we have dramatically reduced and then eliminated our use of progrow. Where we suspect that a crop such as cauliflowers or kohlrabi is suffering from boron deficiency we have used a seaweed preparation called maxi-crop to add more boron. We are attempting to lower the pH and increase the acidity of the soil by adding pine needles and composted leaves. We could add sulphur chips or sulphur dust or sulphate salts such as potassium sulphate, aluminium sulphate or ferrous sulphate but as far as possible prefer to use natural fertilisers.  

Recently coffee grounds have been obtained from local cafés and used as a nitrogen source and a deterrent to molluscs who evidently lose their appetite in the presence of coffee.

It is important to avoid losing soil from the farm during harvesting or weeding, so we ask people to take care to remove as much soil as possible from both the food part of the plant before it is taken home and to shake weeds before they are added to compost heaps.

The first growing season

We were fortunate that the farmer ploughed the field before we began, so we had a bare field with a polytunnel frame in one corner. Otherwise it takes a lot of time to rotivate or dig 4400 square metres of land.

Well weeded cabbages





Impressive onions

Our soil was a fairly heavy alluvial clay with flints set above a chalk bedrock close to the river Itchen. The soil drains fairly well and is fertile, but stones up to 6 inches long keep rising to the surface and require constant removal, particularly if root crops like carrots and parsnips are being grown.



Maturing nicely



Potatoes cover the ground quickly



The courgettes grew very quickly

During our first season we grew 10 crops: potatoes, beans, courgettes, squash, sweetcorn, salad crops, parsnips, carrots, leeks and onions. Each team concentrated on one crop. Some teams had a relatively easy time, others had to work much harder. Salad crops grew quickly but required a lot of weeding and watering, and the team was unable to finish off digging and weeding the whole of their prescribed area. Those growing beans found that constructing frames for climbing beans took a lot of time and likewise they were unable to clear all their plot in the first year. The nice thing about growing courgettes and squashes is that the plants quickly cover the ground and hide the weeds, so people feel that they are making progress. However we had a glut of courgettes (or more accurately young marrows) which we couldn't even sell in the local market, greengrocers and delicatessens. Potatoes are another easy win, but everyone loved our potatoes and we soon sold out. Clearly a better balance of crops was needed! ! However we would advise growing easy big bulk fast growing crops like potatoes, courgettes, squashes and sweetcorn in the early stages and novice horticulturalist will feel a tremendous sense of achievement as they make their first harvest. 

And our weed pile grew even faster



Our weed pile

In the first year there was much ground preparation to be done including destoning plots where carrots or parsnips were to be grown, digging heavy soils, followed by weeding the weeds which seemed to grow even faster than the crops. The soil needed to be weeded very regularly for the first couple of years. Taking weeds out when they are small saves a lot of time later when they have grown, so try to keep on top of weeds (difficult in the early years). Mercifully after three years all annual weeds seemed to be under control in the vegetable plots, but persistent weeds like couch grass and bindweed remain in places. Lesson: don't plant perennial crops until an area of ground has been weed free for a year. We have never used herbicides in the vegetable field in order to be as organic as possible. This does mean that there are patches of nettles grow along fence lines and in other parts of the site, which the majority of members are prepared to live with.