Double digging is a technique where you dig, put the soil to the side, dig a bit more and toss that second lot of soil into the first hole. Essentially, you are turning the soil and bugs upside down and letting their shocked, dead bodies feed the your new plantings. In thin soils (like dryland soils) you would be bringing up the subsoil and trying to turn it into top soil. Double digging is destructive.
Double-Digging can be Instantly Impressive
The growth on plants (and sometimes the weeds) is quick and leafy. Double digging is an old farming technique used for centuries in countries with cool climates, deep soils and a careful regime where the soil is rested for long periods to try to recover. If you are in the modern world where land is expensive and there is pressure on you to do use (no time to rest it), or you want to use the space that is close to your backdoor not far away in a forgotten back corner of your garden. Then double digging is not your best option.
There is a serious cost to double-digging. Put bluntly, double-digging does irreparable damage to your soil. Double-digging
kills the micro-organisms in the soil. The dead creatures make double digging so amazingly productive. Their little bodies become instant fertiliser for the crops.
damages the structure of fragile soils and tempts erosion due to weathering by water and wind.
can bring up the useless, hard clods of subsoil unless you are digging on a rare fertile flood plain.
has a high risk of erosion from the moment vegetation is removed or hard-hoofed animals are put to graze. The typical Australian soil is only centimeters deep. This risk is amplified by the process of digging.
We can buy a fruit tree, dig a hole and put the tree in the ground. In a short time the tree may be fruiting and voilà we have the start of a food forest. Or do we? A real food forest captures condensation (more condensation can come to your garden than rainfall). A Permaculture forest builds soil. Condensation is trapped and rainfall stored in the soil. Water is used and re-used. Organisms are nurtured not sacrificed. A good permaculture forest design optimises the use of natural energies and serves to increase the health of the soil. Healthy soil gives us healthier trees and more nutritious fruit.
What Soil Really Wants
Good soil has 5 components:
Air (digging does increase the air, but so do worms)
Water (digging can increase water penetration) but if not designed well it can lead to erosion
Micro-organisms (digging kills many of these). Mulching provides them habitat
Nutrients (plants including weeds can mine for nutrients and make good air pockets with their long roots) Biochar can boost the nutrients in the soil as well as increase habitat for micro-organisms.
rock or other growing media such as recycled brick.
No-dig gardens can be designed to capture and filter the rain-water and protect the soil and micro-organisms from erosion. No-dig gardening
is physically easier and faster to set up
can regenerate soil (fertile, rocky, sandy or solid clay)
requires less effort
uses waste materials and
evolves into a beautiful garden
No dig gardening requires a little patience but the soil is regenerated, fertility is enhanced and the organisms are constantly building in numbers.
Joyous Songs of Worm Charmers
There are many traditional farming techniques where the nutrients and organisms in local forests are brought to their fields to ‘seed’ worms and nutrients into the fields to improve fertility. Some people have turned it into a quirky sport like worm charming.
It’s that time of year when a lot of our best food is thrown in the bin. [A staggering 20% of food is thrown out annually.] Thousands of dollars in nutrient wealth is lost by humanity and the environment.
The best use of left-over food is to eat it next day (hence the term ‘giving someone the cold shoulder’). The second best use is to make it into something different (meat-loaf, curries, lasagne etc). Third best use is to preserve it (freeze it, pickle it etc). The next best use is to feed happy domestic natural recyclers chickens, worms or soldier-fly farms]. But if the food is off, the question of finding the best composting technique arises.
Healthy Compost – Good For Everyone
Who cares about the state of our soils? Most soils in urban areas are compacted, depleted, polluted and lifeless dust. Recreation areas, streets and water ways can be rich in heavy metals and pollutants. Healthy soil means healthier living for everyone.
There’s no doubt that compost is the best tool for healthy soil. It holds moisture, gives nutrients, and brings dead materials to life, it can break down many types of pollutants and correct acidity.
One cup of compost can eventually renew a whole garden. It demonstrates the paradox of life – it can replicate itself. But very slowing, especially if you tread on it, take food or ‘weeds’ or grass clippings away or limit it’s food source (leaf litter, food scraps etc). Compost is one of those rare resource that we can’t have too much of.
Compost is also a fabulous way to reduce the amount of waste going to landfill. When food scraps are sent to landfill, they are covered up and this causes anaerobic decomposition. “Eventually this releases methane, a greenhouse gas that is 21 times more potent than carbon dioxide”. A similar process can occur in neglected compost bins in the home.
Why the hot debate? Let’s dump the tragic stinky compost image and brush up on this life-enriching practice.
Better Compost Techniques
In the forest, the composting system works slow and steady. On the farm, nutrients are being shipped off to market and need to be replaced quickly. In urban gardens and garbage bins, the compost is often sweating, choked by layers of random debris including deadly plastic.
In the forest, the fruits are eaten by birds, bats or other wildlife. Their manure feeds the forest plants and fungi. A permaculture food forest that is supplying healthy food for a community needs to be managed so there is enough food for people as well as the forest and the wildlife.
In a Permaculture food forest, we aim to:
grow fruit that is less likely to attract pests and disease. We can invest in hardy varieties by not giving the weak varieties special treatment. Mark Shephard uses this breed-them-tough attitude at New Forest Farm. This doesn’t mean we have to abandon rare varieties, quite the opposite. We can try rare fruits and may stumble across one that suits our bio-region well and tastes great. We need to allow for losses due to experimentation in the permaculture plans.
avoid composting methods that feed pests, rodents and disease. In Australia there is an indigenous pest that is spreading rapidly with climate change. The Aussie fruit maggots destroys fruit as it ripens. It has now spread south into the traditional agricultural fruit-belt of the nation. There are hundreds of food plants that do not get fruit fly – invest in these. Try something different for lunch.
Good Thermal Composting
Thermal composting kills weed seeds, has bacteria that break down many oils and synthetic chemicals including anti-worming medicines that may be found in horse manure. Hot compost hosts natural bacteria to break down the material into accessible nutrients. We need to monitor the compost temperature well to check that it is ready. If we use it when it is still too hot it will not only cook your plants it will rob them of nutrients. The plants can go yellow and look sickly. [You can perk them up with some liquid manure or worm-farm waste]. Essentially, try to keep your compost in piles while they are hot. Let the pile get burning hot and wait until it cools down before putting applying it around fruit trees.
Double The Value Of Your Compost!
Let’s apply the Permaculture principle of multiple uses for each element in the design. We know the compost pile can get really hot so, we can use this heat to kill a weedy patch. Hot compost can even provide some hot water. If you don’t want any of the rich nutrients to escape you can put your hot compost pile onto a recycled tarpaulin, then when it has cooled off, remove the tarp and plant into the rich soil below.
The easiest ways to compost without worry are to use a worm-farm, soldier-fly farm or sealed drum that you can rotate.
A ‘Super-tree’ produces flammable nuts, has leaves that can burn wet, produces abundant fruit, supports a web of life, grows large enough to live in, provides timber that never rots, survives thousands of years, supports a wild-life of fungi underground, and holds steep slopes on mighty mountains. Many can regulate the temperature around them by moving liquids up and down the trunk, dropping leaves and expiring vapours to cool the air. Remarkably, some trees can communicate through their root systems for miles underground. Mature trees can even send warnings and protective chemicals out to younger trees.
10 Special Powers
Trees provide Fuel, Food, Oils, Forage, Structural, Conservation, Carbon sequestration, Soil managers, animal barriers, and Fungal & Microbial habitats.
Fuel trees provide a range of fuel options including solid fuel, flammable leaves, bark, oil or flammable ‘candle or diesel’ nuts.
You don’t always have chop a tree to get fuel. Solid fuel from trees sometimes falls naturally. The windfalls include flammable leaves, cones, nuts, fallen branches, harvested sap, and resin.
David Holmgren writes that solid fuels are the most useful energy resource globally. We can plan for their harvest, they are easy to cut, require little training to use, convert easily to energy, are hard to steal or vandalise, and renew themselves.
Eucalyptus leaves have the power to burn whilst wet. Even more amazing, diesel and petroleum trees have nuts that burn like candles. Meet the Brazilian tropical rainforest tree Copaifera langsdorffii commonly known as Capaiba (Tupi Indian word cupa-yba). It is several powers. This ‘diesel tree’ is also a soil-enhancing legume. The resin is tapped sustainably like maple trees. Another, Pittosporum resiniferum, provides a form of n-Heptane.
Overall, most trees produce woody material suitable for the generation of BioGas fuel. This means alternative wood-based fuel is available without killing trees. Simply coppice or pollard instead.
More than 80% of the world’s food species came from the rainforest. Fruits, nuts, tea, coffee, chocolate and alcohols such as cider come from the bounty of trees.
The permaculture food forest usually intercrops fruit and layers of nut trees. We use strong food trees to support vine crops and short-lived trees act as nurse trees to maturing species. Tall evergreen trees are positioned in the shaded corner of the orchard and often used as wind-breaks.
Herbal, medicinal, culinary and cosmetic oils come from trees. These include Eucalyptus, Pine, Olive, Avocado, Walnut, Pecan, Almond, Cashew, Macadamia, Frankincense and Myrrh and Neem. Teatree is a hard-working fungicide (ok, it’s a shrub but worthy of mention.) Coconuts are not really trees either but they are tall, fragrant, yummy and an excellent make-up remover.
Other tree oils such as Tungoil (Vernicia fordii) when mixed with the natural cleaner and thinner Limonene (oil of citrus fruit peels) is a beautiful floor polish and useful for coating and preserving woodwork.
Fodder is an excellent food for grazing animals. The art of fodder planting almost forgotten conventional farming. Many trees provide excellent, nutritious fodder for animals. Fodder from trees is available during dry years. Fodder trees can be grown as living fences,(applied at Avonstour) hedges or as shade trees in the corners of paddocks. The tree roots can extend deep into subsoil, mining minerals that grasses may not reach.
Cattle browse and shelter beside fodder trees. Their manure is happily filtered by the abundant layers of forest shrubbery and leaf litter beneath. Forage Examples include: Oak, Poplar, Acacia aneura (Mulga), Albizia Julibrissa (Leguminous, deciduous, fast growing, regenerates) Dodnaea viscosa (Hop bush).
Above all, fodder trees provide food, shade, windbreak, pollution filter and living fences. Forage Examples include Oak, Poplar, Acacia aneura (Mulga), Albizia Julibrissa (Leguminous, deciduous, fast growing, regenerates) and Dodnaea viscosa (Hop bush). Better still, plant a guild of native trees to support wildlife and local fungi.
5. Structural Trees and Timber
Many trees grew large enough to shelter a traveller. Plato wrote about trees in his homeland, Greece, that were too big to put his arms around. Few large trees remain there. Shipbuilding claimed most of the great trees of Plato’s era. But still today, trees war and poverty continue to destroy trees.
Throughout the eras, material from trees has provided us with complete houses (roof shingles, frames, and plastered wattle walls), canoes, ships, furniture, garden tools, the first cars, musical instruments, cricket bats, rainboots, clothing (silk, rayon, viscose) and much more.
6. Wildlife Habitat – Humanities Bank of Genetic Capital
The conservation of wildlife habitats makes good economic sense as well as ethical sense. Healthy forests as a bank of diverse genetic material. Most of the plants, insects have not yet named. Their potential lies undiscovered. Surviving forests require nothing from mankind except respect. They are a self-supporting bank of unknown resources.
Humanity may be able to create clean air, water, soil, and mine more nutrients. But we can’t recreate genetic material. If we did discover how to recreate genetic material, a lot of creativity, science and energy would need to be invested. It is cheaper to safe-guard the genetic material existing today.
7. Carbon Sequestration
Trees are the cheap. They work day and night aslong-term storage units soaking up excess carbon. They help mitigate or defer global warming and slow climate change. But recent research is showing that some trees are hitting their limit of absorption. This startling situation demonstrates we need more trees to combat the growing climate crisis.
Long-living trees are excellent guardians of carbon. Many trees live thousands of years (including olives) however, clonal colonies of trees have the potential to be immortal.
The oldest known clonal tree is Pando, an 80,000-year-old colony of Quaking Aspen. Unfortunately, the tree releases sequestered carbon when it dies. So, we need long-living self-replicating plants.
8. Soil Management
Trees hold the banks of steep slopes, trap centuries of silt, create their own rain and micro-climate. Trees have been shown to seed the clouds to help make rain. The process of soil enrichment can be accelerated with Huglekultur, Synergistic gardening, and Biochar.
Garden Mounds with Wood
Austrian, Sepp Holzer, pioneered Huglekultur for raised beds. The wood in the base of Huglekultur mounds holds moisture, builds fertility, adds height. This provides more surface area for intensive gardens growing vegetables and herbs. Similarly, Synergistic garden mounds, developed first by Emilia Hazslip, can also incorporate wood. Position mounds to harvest rainwater, deflect frost, create various microclimates, and slowly move the water through the system.
Soil Enrichment with Wood By-products
Biochar, formerly known as Terra preta, is low temperature-carbonized biomass commonly made trees. For thousands of years, it has been the lifeblood of native south-American intensive agriculture. They convert lumbar into a habitat for the accelerated growth of soil micro-organisms. Activated charcoal also sequesters carbon.
Biochar can be made as a by-product of heating the home. We make biochar in our fuel stove using a loose lidded container inside the firebox or by covering the flames with ash before going to bed. Ash from the fire is separated from the charcoal. We turn the charcoal into biochar by crushing it in a bag when cool then adding it to the compost toilet mass.
Ash is an excellent source of insulation material. Or it can provide valuable nutrients and pH modification to garden beds and poultry house floors.
9. Animal Barrier Systems
Hedges can be stronger, longer-lasting, and more durable than fences.
Nature is free and choatic. But not all hedges have to look messy. In fact, when the edges are neat, most people think the garden looks today. In truth, nature can work happily within tidy boundaries.
Some hedges can be trimmed to sit up off the ground to allow small creatures to pass underneath but block out larger animals, people, and cars.
Hedging in England is an art form, with quirky regional variations. In Dartmoor, the trunks of young trees are half-cut and pushed horizontally. Similarly, each sapling gets half-cut and tipped onto the previous sapling. In time, the side branches start to grow upright. This method makes a thick and durable fence providing habitat for wildlife such as insect-hungry birds.
10. Fungi and Microbes
Incubation converts tree sugars into energy.Paul Stamets shows how mushrooms can save the world by providing a usable energy source for domestic and commercial systems.
Trees produce a lot of goods and services worldwide. Observation is the key to Permaculture. Through observation we build our knowledge and community understanding of plants and their beauty. Here is April’s celebration about what there is to love about Trees.