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Permaculture Design/How to/Some ways to improve your soils
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Traditional classifications of soils
soil
Colour
Colourless/white: high silica content
Light/white: lack of oxygen; leached; high calcium; alkaline ph
Yellow: lack of oxygen; high clay content; aluminium & iron
Red: iron oxide
Red/brown: volcanic basalt origin; iron & magnesium
Black: rich in organic matter & nutrients; holds moisture
vegetation
Azalea, dandelion: acid soils; usually leached; often
berries, conifers, dock: compacted with poor drainage
saltbush, spinifex: alkaline; saline; dry soils
nettles, clovers, vetch: excess nitrogen; low humus content; low microorganism content
blackberries: open disturbed soil, possibly acid
bracken: recent fire; general decline in soil fertility.
buttercup: poor drainage, acid.
thistles: low calcium & iron content; hard soils.
chicory, chickweed, clover, groundsel: good fertility
parent material
Eg soils derived from:
Sandstone: sandy, high silica.
Shale: clay; high silica & iron.
Basalt: high iron & magnesium.
smell
Sour: Lacks oxygen, acidic, sulphur dioxide
Sweet & earthy: high oxygen, good soil life & OM
Garlic: arsenic in soil.
taste
Smooth & slippery: acidic, soil water lathers easily
Weak soda: alkaline/mineral; won’t lather easily
soil life
Worms: good moisture, OM, low pesticide residues
Ants: drier, sandy
Slugs & snails: damp, decomposing plant & animal material.
Skinks & lizards: warm sunny, dry spots, good insect populations
water
Run –off: is increased by bare ground, compaction, steep slopes
Repels water: compacted, eroded, excessive use of dolomite, very little OM, sandy & allowed to dry out & has formed a moisture resistant barrier
Shrinks & swells: high clay, holds water, cracks.
Fast draining: hole filled with water, drains within 10mins: erodes easily, collapses easily, few fungal diseases, good movement of water & soil life. Not good for dams.
history
Bare ground: agricultural or industrial contamination.
Growth in poor soils:previous structures, compaction, old poultry or animal pen site
No topsoil:quarry or fill site, erosion.
Bad cracks & rubbish:old tip or landfill site
plants and soil minerals
Often plants which grow in deficient soils have the ability to concentrate those missing elements in their structure.
Potassium present ~ marshmallow, knapweed, wormwood, opium poppy, fumitory, tansy & borage. Deficient ~ red clover. Celery & leek like potassium. Chicory is potassium rich.
Calcium ~ buckwheat grown as a green manure or composted adds. Melon leaves are a source of it & oak bark is especially rich as are all thistles & willow. Dandelion “mines” it. Peas, beans, brassicas & turnips need it.
Phosphorous ~ bracken indicates a lack of it & accumulates it. Burn it & spread the ashes. Valerian & comfrey are rich sources. Whitefly indicates a deficiency along with magnesium. Brassicas need it to head well.
Iron ~ blackberry is a rich source.
Magnesium & sulphur ~ broom, salad burnett, plantain, & sheep sorrel (for magnesium)
Ragwort ~ copper
Thistles ~ nitrogen, copper & silicon.
Creating resources on your land
Soil regeneration
Plant mulch making plants ~ comfrey, tree lucerne, grasses for hay, weeds such as dandelion, plantain, nettles, borage, deciduous trees.
Use small prunings as part of the mulch around your trees. Place them over soil that you need to add organic matter like grass clippings, weeds, & manure on top & let nature do the rest. Once it’s reasonably broken down sow seeds/plant. Good way to establish areas for under-planting an orchard/food forest.
Harvest local resources ~ bracken & chicory are high in potassium, add it to your compost, burn it & use the ashes around plants such as, celery & leeks. The brassicas (cabbage, cauli, broccoli, brussels) need phosphorous to head up well, comfrey & bracken supply it. Ragwort concentrates copper. Broom is high in magnesium & sulphur, lupins in nitrogen & calcium. Seaweed has many of the essential trace elements that plants need. Food scraps from cafes & super markets add to the mix for your compost.
Other Strategies
Plant wind breaks to filter air-born pollution and prevent soil erosion.
Plant trees & shrubs to take up ground water pollution e.g. alongside a road, runoff from your neighbour who uses chemicals. The leaf litter from deciduous trees and shrubs also adds organic material to the top layer of your soils. Over time this will be a significant addition.
Create wetlands planted with macrophytes (reeds & rushes) to take up the above pollution.
Use raised beds for growing in.
Seaweed, compost & dolomite help to clean soils of pollutants such as heavy metals.
Allow weeds to grow ~ add OM, take up pollutants.
Spread rock dust to supply minerals ~ basalt, granite, dolomite.
Where practical, change the contour of slopes to create swales so that water does not run off as quickly and cause erosion.
Don't leave bare soil, plant something instead -- or at least lay down some mulch.
Remember that the more conditions you create for soil life to thrive the better your soils will be. Create diversity.