
                          GARDENING WITHOUT DIGGING
                               NEIL BARRACLOUGH

This is intended as a discussion paper only, the author only having two years
experience in gardening by the method described and is at this stage
continually changing his approach to various aspects of gardening. There are
no restrictions on copying this information.

Methods of gardening with minimal or no digging have been used for the home
garden for quite a long time, of later years made popular by people such as
Ester Dean. In 1965 "Victorian Compost News", a quarterly newsletter put out
by the Organic Farming and Gardening Society has an article describing various
methods of gardening without digging and names two people who had previously
been using a no-dig method with lucerne hay as a mulch for the twenty years
previous to the article having been written.

Lets start by giving a bit of thought to the natural situation. Dead leaves
and other vegetable matter falls on the surface of the soil, this is broken
down by bacteria or eaten by earthworms that may excrete it at a depth mixed
with soil. A teaspoon full of healthy soil may contain about 150 million
living bacteria, perhaps one percent by weight.

The soil is a living thing. Some bacteria breaking down vegetable material and
making the nutrients available to plants, others secreting acids and various
other chemicals that make minerals in the soil available to plants. There are
protozoa that consume bacteria, often being an effective check on those that
cause disease.

Plant roots penetrate, often deeply, into the soil and these roots are more
than just a means whereby the plant takes up water and minerals. The plant
roots secrete sugars and other substances which nourish bacteria that exist in
a symbiotic relatioship with the plant. The bacteria may protect the plant
from antagonistic bacteria or they may make nutrients available from the soil
that would normally be in a form that the plant could not use them. Different
plant species secrete different solutions and thus each produce differing
cultures of bacteria around their roots.

As well as the great variety of microscopic life of the soil there are a
variety of soil fungi. The microscopic life forms in the soil should be in
balance and our gardening practices should be in harmony with this balance. If
we dig in manure or organic matter we are upsetting the order.

When gardening without digging organic matter is placed on the surface as a
weed supressing mulch rather than being dug in. The surface is where organic
matter accumulates in nature and its there that the bacteria are best able to
break it down. Worms take it down into the soil below and the roots of the
plants also help to add organic matter to the soil.

Starting the garden:

Its perhaps best to chip the grass cover from an area with a mattock or hoe
before starting a garden but it can be started on grass if there is enough
mulch to provide a good thick cover. When preparing an area be aware that the
following plants if not removed can be a problem later - Dock, has a deep tap
root and if this root is not removed the plant will continue to grow up
through the mulch. Kikuyu grass should be removed from the site and burnt, a
very invasive weed in any type of gardening. Couch grass is also a problem and
also should be removed from the site. Onion grass, grows up through the mulch
if the underground bulbs are not removed.

I clear an area, cover it with mulch and only use quick growing annuals as the
first crop. When the crop is finished any persistant weeds are removed. Unless
dock is going to seed it and onion grass are best removed after the first crop
has come out. Dock has a long tap-root which must be removed and onion grass
has an edible bulb which should be dug out. It is esential that any weeds that
do come up are removed before they seed and if posible from now on only use a
seed free mulch.

Having cleared the area now it's time to lay out the mulch. Mulches should
have the following characteristics- Be as natural in origin as possible and as
free of undesirable chemicals as possible. Free of weed seed. They should be
of a fine enough texture so that they don't provide cover for slugs, snails
and other pests but not so fine that they restrict air or water flow. As well
as adding organic matter to the soil mulch surpress weed seed germination. If
the mulch cover decomposes then weed seed will germinate so for this reason
the mulch should be of a type that won't break down quickly. Also it must be
realised that mulching is an on-going thing with areas to be mulched perhaps
at least twice a year.

Hay or straw is excellent in many ways but can have many weed seeds in it.
Second or subsequent cuts of lucerne is considered the best type of hay as it
tends to have few weeds and being a legume has a higher nitrogen content than
straw or grass hay. There could be advantage in spreading hay out in the chook
run for a while to allow the chooks to eat any seed they can find. Wheat straw
or oat hay that chooks have had access to may then be virtually seed free.
Perhaps the best hay of all is pea hay. Experiments are about to be conducted
on boiling hay in a 44 gallon drum to kill seed.

Hay can often be obtained from the animal pavilions after the local
Agricultural Shows or may be available free if you can find a farmer who wants
the loose hay cleaned out of his shed. From August till November is the time
to watch for loose hay as this is when the sheds are most empty. Keep an eye
on the place where farmers store round bales, after they have been fed to the
stock there may be a residue of partially broken down hay remaining on the
ground.

Other suitable mulching material could be-

Grass clippings: Careful of any from local tips. Many councils spray lawn
clippings in the tip to prevent flies breeding in them. Lawn clippings break
down quickly and this is a disadvantage for a mulch. Also lawn clippings are a
potential source of weed seed and if from an unknown source may contain either
cooch grass or kikuyu. If transporting them any distance there is very little
organic matter by weight. Lawn clippings have a high water content.

Sawdust: On its own not a recommended mulch, it tends to restrict water
penetration and is very low in nitrogen. Sawdust has a very good organic
matter to weight ratio and is often readily available. Its seed free and if
from a sawmill free of undesirable chemicals. Being nitrogen deficient it will
slow down the de-composition of lawn clippings and both compliment the other.
Caution should be used with pine sawdust, perhaps in moderation and only then
with strawberries. If any sawdust is used as part of the mulch then it may be
advisable to keep a few legumes (peas, beans) growing in each rotation.

Pine needles: Excellent with strawberries which are native to conifer forests,
good for blue berries and for raspberries. There are reports of pine needles
having been used as the main mulch for no-dig gardens and if you live near a
pine forest then it would be well worth doing some experiments. May create
acid conditions or contain resins that harm some plants, however where I use
pine needles to mulch strawberries the weeds that are there are still very
healthy.

Sea grass, sea weed: Provides a good mulch that has all the desirable
characteristics but if its from the Gippsland Lakes questions arise as to how
chemical free it is. Leaves raked up in autumn would also be excellent.

I generally start a garden bed with a layer of hay, perhaps some compost mixed
in with it and a layer of lawn clippings and sawdust on top. Potatoes can be
planted directly on the bare ground below the mulch but the plants must have
mulch added again when about 250mm high and care must be taken to make sure
that the tubers are never exposed to light. To plant larger seeds such as peas
or beans, part the mulch and put a hand full of compost on the bare soil and
plant your seed in it, cover with mulch. The same for transplanting seedlings
but let the foliage show through the mulch. Vegetables which require small
seeds to be planted, such as carrots or pasnips can only successfully be
planted in an established bed.

If newspaper is to be used as an additional weed supressent then 2-4 sheets
can be placed between the hay and lawn clippings/ sawdust.

For subsequent mulches a lawn clippings and sawdust mix is good or a seed free
hay can be used. If you have a mulcher/shredder machine then you can make up
some mulch with it. Wattle leaves are excellent shredded. It is intended to
grow green manure crops of oats and either tick beans or broad beans over
winter in vacant beds and use the crop as the initial mulch in spring.

There is probably a place for plain brown cardboard as a weed supressing mulch
in the organic garden but I am wary of using newspaper with its ink. My
information is that newsprint ink is a product known as "Carbon Black"
dissolved in a solvent. Carbon Black is made from incineration of a variety of
industrial wastes and if so could be expected to contain a variety of
contaminents.

I use sawdust to a depth of about 100mm for the paths and when it breaks down
add it to the mulch on the garden bed. I then put down a new lot of sawdust on
the paths. This is a very effective way of adding orgnaic matter to the
garden.

Fertilising and mineralising the soil:

Organic gardeners differ from others in their veiws on the use of many
fertiliser. Its impossible to give an in depth explanation of the many reasons
in the space available nor am I qualified to include anything but a few words
of brief explanation.

Trends in agriculture have been towards providing adequate amounts of the
major elements in a soluble form. ie; nitrogen, phosphorus potasium, calcium,
magnesium, zinc, copper, molybdenum, boron, clorine, and sodium.

The problem with soluble fertilisers is that the plants tend to take up too
much of certain elements, resulting in inbalances within the plant, which in
turn affect the plants ability to resist fungal and other desease problems or
even make them more attractive to insect pests. The imbalances within the
plant may also mean that the plant is inferior nutritionally to organically
grown produce. Providing elements in soluable form will in most cases upset
the delicate microbial balance in the soil previously described. The use of
synthetic nitrogen fertilizers reduce the nitrogen fixing bacterias ability to
fix atmospheric nitrogen.

The loss of the nitrogen produced by the nitrogen fixing bacteria is about
proportional to the amount of nitrogen added. Any gain in vegetable growth
results from an addition of nitrogen in excess of the amount that was
initially being produced by the bacteria.

The addition of nitrogen by the application of synthetic fertilizers reduces
the Vitamin C content proportionally, the greater the amount of fertilizer the
less the amount of Vitamin C.

The addition of nitrogen by the application of synthetic fertilizers may cause
plants to store quantities of nitrates and nitrites, this is particularly so
with green leafy plants. The nitrates and nitrates have been associated with a
number of health disorders.

Manure contains nitrogen in soluble form and I believe its use should be
treated with caution and it only enters my garden through the compost heap and
even then in very small amounts. Note the luxuriant growth around a cowpat and
also note that grazing animals will avoid it.

Though hesitant to go against conventional wisdom I would question using such
products as "Dynamic Lifter" or any other manure based product in a garden
situation in anything but extreme moderation.

Superphosphate is avoided by organic followers because of its acidifying
effect. By lowering the pH of the soil it can cause some elements present in
the soil to become unavailable to the plant. Superphosphate aslo has cadmium
and fluoride in concentrations considered by many to be harmful. The latest
news is that cadmium, a heavy metal more poisoness than lead is showing up in
the food basket in increased concentrations and this has been attributed to
superphosphate use. Superphosphate provides phosphorus in a soluable form and
this is not recommended.

Organic management seeks to apply deficient elements in an insoluble form, so
that the element is only slowly released to the plants through microbal action
and other mechanisms.

Though rock phosphate is accepted by many within the organic movement some
have questioned this as a posible source of cadmium and fluoride
contamination. However there is a new product on the market that has a very
low analysis of both these.

Organic followers favor dolomite over lime as dolomite adds magnesium as well
as calcium. Though lime may be a cheaper way of neutralising acidity its use
may lead to magnesium deficiencies.

Gardening without digging seems to provide a more natural environment for the
many and varied lot of little critters that are a necessary and joyful part of
the garden. There are a great abundance of ants whose nest would be destroyed
if the ground were dug. Spiders and lizards abound, slaters who help the
decomposition of decaying vegetable matter. The occassional frog is a joy when
seen. Fruit trees, raspberries, brambles, gooseberries, grapes and other
useful shrubs or vines should all be part of the over-all layout and combined
with the vegies, there is no need to keep them all separate as properly laid
out should complement each other. Trees and shrubs being more deeply rooted
bring up minerals and make them available to other vegetables through the
decomposition of their leaves that fall on the ground below. Strategically
placed tall plants give pest controlling birds security. Perhaps a small pond
or two, as this will attract dragonflies and increase the diversity of fauna
in many ways.

Learn what conditions each plant type likes and provide it in an overall
design. Make each bed as diverse in its species composition as practicable
while following companion planting convention.

Even poke in a few flowers and add a bit of color. Hover Flies, which in both
laval and adult stage eat aphis, collect a small ball of pollen to lay an egg
in so a few flowers about will attract them and help control aphis. Let a few
of the vegies go to seed and perhaps save your own for future planting. If you
want further information on gardening without digging feel free to ring me

   ========================================================================
Document prepared Nov 1990 by:
    Neil Barraclough,  50 Rosstrevor Ave
    Briagolong, 3860.  (051) 455290

For further information contact the:
    East Gippsland Organic Agricultural Association Inc.
    PO Box 1263, Bairnsdale
    VIC 3875
