organic soil care - garden organic soil care 8 tel: 024 7630 3517 ... peat or coir as a soil...

Organic soil care

8 Tel: 024 7630 3517 • [email protected]

A healthy soil is the basis for growing healthy plants and healthy food. The soilis full of life – worms, fungi, bacteria and other microscopic creatures – whichcreate its structure and fertility. When looking after your soil organically youwill be improving the diversity, and supporting the activity, of these vitalcreatures. You will be avoiding activities and inputs that disrupt and harm thesoil ecosystem.

Techniques Activities and practices for organic soil care

Best organic practice – the first choice

Get to know the soil you are working withGrow plants that suit the existing soil conditions. Where necessary, use organic methods to improve the soil, but don’t try to change soil conditions too drasticallyKeep the soil covered with growing plants, green manure cover crops, or an organic mulch. This protects and improves the soil structureGrow green manures to improve soil structure and to recycle, and add,plant foods. This includes clover in lawnsMaintain soil humus levels, biological activity and fertility, wherenecessary, by applying home made compost, or other bulky organicmaterials in appropriate quantities and at the appropriate season (seepages 8-11, and factsheets.)Recycle organic kitchen and garden waste within the garden, by makingcompost, or through other processes such as making leafmouldUse a crop rotation (see page 7)No dig techniques

Acceptable organic practice

Minimal soil cultivation, as necessary

Acceptable, but not for regular use

Rotavating, to clear ground or turn in green manuresDigging between November and February, other than on clay soils to leave ground exposed to frost

Organic soil care

9www.gardenorganic.org.uk

Never acceptable in an organic garden

Using excessive quantities of nutrient rich manures and fertilisersUnnecessary digging, rotavating and other soil cultivations Growing food on potentially contaminated soils, such as brownfield sites, unless analysis shows that the levels of contamination are acceptable (see )

Crop rotation

Crop rotation is an essential technique for managing soil fertility, and for pestand disease control.

Briefly, crop rotation means not replanting the same type of plant, or anotherof the same family, in the same site for a period of years. It is most often usedwith annual vegetables, but the same principles can be applied to perennialfruit crops and other plants.

• An interval of at least 3 years, or more between plants of the same family, or longer if necessary where a specific problem is identified

• Include nitrogen fixing green manures in a vegetable crop rotation• In a greenhouse, where a 4 year rotation may not be possible, pay particular attention to building and maintaining soil health

• Alternate fertility building crops with those which take a lot from the soil• Alternate weed suppressing plants with those that compete poorly with weeds

Garden Organic factsheets

Composts and manures in the organic garden Contaminated soils, manures and plant wastesCrop rotationGreen ManuresHow to make compostKnow your soilManaging your soilMulches for weed prevention and control Using woody garden waste

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Organic soil care


Bulky organic soil improversBulky organic soil improvers are materials such as garden compost and strawymanure; they are bulky, as compared with a bag of fertiliser, and theiringredients are ‘organic’ in that they are of living origin. In an ideal world theywould all contain only organically grown ingredients.

Bulky organic soil improvers are generally ‘waste’ materials. Recycling plantand animal wastes in the soil imitates the recycling of nutrients carried out innature, and is the mainstay of organic soil fertility.

Bulky organic materials are high in plant fibre, which is a vital food for the soillife that builds and maintains the soil structure. They also contain plant foods, inlevels that will vary between different types of material, and how thosematerials have been stored.

Waste materials from your kitchen and your growing plot should be your firstchoice. Then try and source further materials as locally as possible. Manures,straw or hay should be obtained only from organic, or low input systems.When buying ‘commercial’ products, choose those with an organic symbol, orwording, from an approved organic certification organisation, where possible.

Storing and processing plant and animal wastes

Bulky plant materials and animal manures should be composted or left to rotdown before use. The composting process stabilises the material, reduces ordestroys pathogens and weed seeds, and makes the materials easier to handleand apply. Keep the heap covered to reduce loss of plant foods (which can bewashed out by rain) and prevent weed seeds being blown onto the heap.

Materials from non-organic sources should be composted or stored for at least6 months before use.

Rates of useIt is important not to ‘overdose’ the soil with nutrient rich manures andcomposts. This is wasteful of resources, can cause pollution, and can encourageexcessive growth that is more vulnerable to pest and disease attack. Forrecommended rates of use see page 13.

Organic soil care


Bulky organic soil improvers – Plant wastes


Home made compost, and worm compost, made from weeds and plantresidues; kitchen waste; low grade paper and card; other compostablehousehold ‘waste’Autumn leaves and leafmould Shredded woody pruningsLawn mowings, comfrey leaves and other fresh green materials. Thesemake ideal compost activatorsAll the above should come from within the individual garden (orallotment, field, growing plot) Grow green manure cover crops


Autumn leaves from local parks, cemeteries and other traffic-free areasBought in composts made from green waste and other materials approvedin these guidelines. Ideally with a recognised organic symbol orconforming to PAS 100 standardStraw and hay, from organic sourcesShredded prunings from local sourcesChipped or shredded wood – from wood not treated with preservativesComposted bark, from Forest Stewardship Council (FSC) forests,preferably organically approvedSawdust and wood shavings, preferably from local sources, from woodnot treated with preservativesOther local waste plant materials, such as bracken and spent hops,composted before use if not from a certified organic sourceMushroom compost from certified organic sources

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Organic soil care



Straw and hay from non-organic, non-intensive systems. Check withsupplier as to what herbicides have been used; some may harm plantsMushroom compost from non-organic mushroom producers, storedunder cover, or composted, for six months before use


Peat or coir as a soil conditionerLeaves from busy roadsides and other polluted locationsLeaves and leafmould collected from woodlandsAny materials contaminated with excessive levels of potentially toxicelements, (see ).

Organic soil care


Bulky organic soil improvers –Application rates and timing

Material Timing and Maximum rate of application

Compost – garden,home made

Apply in spring, summer, or early autumnUse up to 1 wheelbarrowful per 5 sq. metres per year

Compost – green waste Apply at any timeUse up to 1 wheelbarrowful per 3 sq. metres per year

Compost – worm Apply in spring, summer, or early autumnUse up to 1 wheelbarrowful per 10 sq. metres per year

Leafmould Apply at any time, in a layer 2-3cm deep

Manure – straw basedanimal manures (ex. poultry)

Apply when well rotted, in spring, summer or early autumnUse up to 1 wheelbarrowful per 10 sq. metres per year

Manure – poultry, withbedding material

Apply when well rotted, in spring, summer or early autumnUse up to 1 wheelbarrowful per 20 sq. metres per year

Topsoil


Where the layer of topsoil is inadequate, or nonexistent, bought in topsoilconforming to BSI standards, can be used, along with the materials listedin this bulky organic soil improvers section.

Bulky organic soil improvers –Animal wastesOrganic farms, apart from some poultry farms, must recycle manures on the farm, so you are unlikely to be able to obtain certified organic manures. Try tosource manures from ‘free range’ or low input farms/smallholdings. Do not usemanures from factory farming systems or where animals have been fedgenetically modified (GM) crops. The way in which these materials are stored, orprocessed before use, and the rates and timing of application is vital to theiracceptability in organic growing (see pages 10 and 13).


Well rotted manures and bedding from herbivorous pets, and anylivestock kept in the individual garden (or allotment, field, growing plot),applied at appropriate rates and times


Straw-based horse, cattle, pig, sheep and goat manures, from organicsystems. It should be well rotted before use and applied at appropriate rates and times


Straw-based horse, cattle, pig, sheep and goat manures, from nonintensive systems. It must be well rotted before useWood shavings based horse manure. This must be very well rotted before use Poultry manures from non intensive egg and meat-producing systems. Commercially available, composted, straw-based animal manures,preferably with an organic symbolChicken manure pellets – see Animal based fertilisers, page 15


Manure applied in late autumn or winter monthsFresh manuresManures, and processed animal by-products, from intensive farmingMaterials polluted with heavy metals and other pollutants that exceed thepermitted levels, (see )Products containing sewageCompost activators containing artificial fertilisersManures from livestock fed on genetically modified crops

Organic soil care


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Organic soil care


Organic fertilisersComposted plant wastes and manures, and green manures (particularly nitrogenfixing legumes), are the main ways of adding plant foods to the soil. Organicfertilizers are only used where a soil or plant deficiency occurs which cannot beremedied otherwise, or where you cannot make, or bring in, enough compost orother bulky organic materials.

Fertilisers suitable for use in an organic garden are of plant, animal or mineralorigin. Most of them are waste products. The action of soil living creatures, orthe weather, makes the nutrients they contain available to plants, in a ‘slowrelease’ way. The mining and/or shipping of some of these products can have anadverse environmental impact, so think carefully before use. Choose a productwith a recognised organic symbol as first choice.

Liquid feeds see page 20

Plant based fertilisers


Home grown nettle, comfrey and other leaves used in a planting trench or as a mulch


Wood ash, from wood not chemically treated after felling, recycledthrough a compost heap.


Dried seaweed meal – from sustainable sourcesFertilisers based on plant waste products and extracts, such as kalivinasse, lucerne, comfrey, cocoa shells

Animal based fertilisers


None


None


Meat, blood,bone, hoof and horn meals, on areas where no livestock haveaccess, and in growing mediaChicken manure pellets, from organic sources only, with a recognisedorganic symbolWool based products, not containing pesticide residues.

Mineral based fertilizers, and materials for raising pH (liming)


Natural forms of calcium carbonate and calcium/magnesium carbonate,including ground limestone, chalk, marl and magnesian limestone(dolomite). Use for raising soil pH, and as sources of calcium andmagnesium.Calcium sulphate (gypsum)Ground rock phosphateAluminium calcium phosphate, where soil pH is over 7.5. (Cadmiumcontent must be less than 90mg cadmium per kg phosphate)Rock dust (stone meal), if a by-product of quarrying


Calcified seaweedSlaked lime Soluble chemical fertilisersQuicklime Guano, urea, Chilean nitrate

Materials to supply trace elements


Rock dust and stone meals if by-products of the quarry industrySeaweed meal and liquid seaweed extractsSulphur dust or chips Calcium chloride solution, for treatment of bitter pit in applesManganese sulphateBorax (for boron deficiency)Epsom salts, for acute magnesium deficiencyFertilisers and liquid feeds containing boron, copper, iron, molybdenum,cobalt, selenium, zinc, sodium

Organic soil care


organic soil care - garden organic soil care 8 tel: 024 7630 3517 ... peat or coir as a soil...

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