Successful vegetable gardens are not accidental. They are the results of
planning, constant care, and the will to make things grow. Among the many things
a vegetable garden may offer toward a satisfying experience are fresh air,
exercise, sunshine, knowledge, supplemental income, mental therapy, and fresh
food, rich in vitamins and minerals, harvested at the best stage of maturity.
Organic gardening differs from "conventional" gardening mainly in
the areas of fertilization and pest control. The organic gardener prefers to use
natural and organic materials and methods, and avoids using practices and
synthetic chemicals that may be detrimental to his health or environment.
The information in this publication should be beneficial to all gardeners
regardless of methods of culture used; however, it is primarily intended to aid
the organic gardener to employ workable methods acceptable to him and compatible
with the philosophy of "organic gardening."
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Consider the size of your family and the amount of produce to be canned, frozen,
stored or sold, as well as that used fresh. Don't underestimate the work
involved in organic gardening.
Choosing a Location ? Select a plot of good, well-drained soil near a
water supply. It should be close to the home for convenience, but should not be
shaded by tall buildings or trees. Enclosing the garden spot with a fence is
usually profitable.
The Garden Design ? Many gardeners find it helpful to draw out on
paper the location of each row and the crop or succession of crops to be
planted.
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Vegetables suited to Florida gardens, leading varieties, seed or plants needed,
planting distances and depths, best time for planting by areas, hardiness, days
to harvest and expected yields are shown in the Florida
Vegetable Gardening Guide (SP 103) .
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Since organic fertilizer and soil conditioning materials are slow working in
general, they should be mixed into the soil at least three weeks ahead of
planting and the soil thoroughly prepared for the seed or transplants. Clumps of
unrotted organic materials not only interfere with the seeding operation, but
may result in nutrient deficiency and possible soil-borne diseases problems such
as "damping-off" of young seedlings.
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A major basis for organic gardening is the use of abundant quantities of organic
material applied to the soil. Usually, it is in the form of animal manures,
plant manures, cover crops, compost, or mixed organic fertilizer.
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- Improves tilth, condition, and structure of soil.
- Improves ability of soil to hold water.
- Improves ability of soil to hold nutrients.
- Improves "buffering" capacity of soil; that is, keeps soil from
"over-reacting".
- Supports the soil's microbiological activity (or the life of the soil).
- Contributes nutrients, both minor and major.
- Releases nutrients slowly.
- Acids arising from the decomposition of the organic matter help to convert
insoluble natural additives such as ground rock into plant-usable forms.
- Helps vegetables survive stress, as from nematodes.
- Helps dispose of organic waste products.
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Under suitable conditions, the organic matter is decomposed by micro-organisms
such as fungi, algae, bacteria, molds, and earthworms. In the process, insoluble
and unavailable (to plants) nutrients, such as nitrogen, are gradually changed
into simple usable products.
For example, nitrogen is converted from the unusable organic forms to
a usable inorganic form through the process called nitrification. Thus,
nitrification is the breakdown of protein (organic nitrogen) into ammonia and
then nitrate. Some of the organic matter becomes part of the soil humus.
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First, materials containing nitrogen must be present. There is a great variation
in the amount of nitrogen the different organic materials contain. Then certain
soil or compost conditions are necessary:
- Proper soil acidity (pH) ?should be about 7.0; in acid situation below 5.5
it ceases.
- Proper temperature of soil ? above 50°F.
- Good aeration ? (does not occur with wet, soggy soil or compost).
- Adequate lime for use by micro-organisms and to keep the soil from being
acid.
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Where animal manures are available, they are probably the best source of
fertilizer and organic matter for the organic gardener. Use manure which has
been aged for at least 30 days, or composted.
Manures vary greatly in their content of fertilizing nutrients. The
composition varies according to type, age, and condition of animal; the kind of
feed used; the age and degree of rotting of the manure; the moisture content of
the manure; and the kind and amount of litter or bedding mixed in the manure.
Table 1 shows average minimal amounts of nutrients to be
expected. They may be as high as 4.5% N; 2% P; and 2% K in some cases. Animal
manures also provide most of the micro-nutrients needed. Some manure products
are composted, rehydrated or mixed with plant litter to enhance their fertility.
How Much to Apply Broadcast
Before Planting
Cow, horse, hog ? A minimum of 25 pounds per 100 square feet (about 5 tons per
acre) of garden soil. For best results, supplement each 25 pounds of manure with
2 to 3 pounds of ground rock phosphate or raw bone meal. Use up to 1 pound per
square foot.
Poultry, sheep ? Apply at least 12 pounds per 100 square feet (about 3 tons
per acre minimum) - or as much as 3 - 4 inches (20 tons per acre).
Other animals? rabbit, goat, and exotic grass eaters ? 10-12 pounds/100 sq
ft. minimum, up to 100 lbs. per sq. ft.
After Planting (As a sidedressing) if needed
Cow, horse, hog ? Sidedress with up to 5 pounds per 100 square feet of row.
Poultry, sheep ? Use up to 3 pounds per 100 square feet of row.
How to Apply
All Types ? Broadcast evenly over plot and spade, roto-till or otherwise work
into topsoil. Apply three or more weeks before planting. A small amount may be
mixed well in the planting hole; however, plant injury may occur with 1 lb. or
more placed in the hole.
How to Apply as a Sidedressing
All Types ? Scatter a band of manure down each side of the row. Place each band
at the edge of the root zone and work lightly into the soil surface. For
individual plants, open a furrow encircling the plant and fill with manure, then
cover.
If a mulch is present, rake it back at the edge of the root zone in
order to apply the band of manure, then re-cover with the mulch.
NOTE: Manure is not always a complete well-balanced fertilizer. It is
advantageous to broadcast a complete organic fertilizer (such as Fertrell) or
ground rock phosphate and potash in addition to the manures.
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Acceptable manure-like organic fertilizer (artificial manure) may be obtained
through the process of composting. Simply put, compost is made by
alternating layers of organic materials, such as leaves and kitchen table
refuse, with manure, topsoil, lime, organic fertilizer, water, and air, in such
a manner that it decomposes, combines, and yields artificial manure.
How is the Compost Pile Made?
The compost pile is made of convenient size, usually not less that 10
feet square (100 square feet) and 3 to 5 feet high. The top should be left flat
or with a slight depression in the center to catch rain or added water. Too much
water eliminates air and slows the decay process.
One way suggested in building the pile is to make a layer of leaves, straw,
grass clippings, and other organic materials 1 foot deep, wet down and pack.
Spread a layer of manure 4 to 6 inches deep over this layer of wet material.
Then spread up to 5 pounds of ground rock phosphate or 1 quart of raw bone meal
per 100 square feet, and 1 pound of ground limestone.
Instead of the rock phosphate and bone meal, you could use 5 pounds of a
complete organic fertilizer such as Fertrell per 100 square feet. Also, a layer
of topsoil is sometimes used.
Then continue to repeat the process until the pile has reached 3 to 5 feet
high.
Compost will begin to heat after 2 or 3 days. Keep it moist, but not too wet,
and do not disturb for awhile.
After 3 to 4 weeks, fork it over, mixing the parts to obtain uniformity.
Fatty animal wastes tend to create bad odors, draw flies and ants; so, try to
avoid their use if this will be a problem.
Compost for the garden should be ready from 2 months to 1 year, depending on
the time of year, type of materials added, and skill of the composter. When the
compost is broken down into a homogenous mixture, and no undecomposed leaves or
other material may be seen, it is ready for use.
What Organic Materials Can Be Used in the Compost Pile
Most anything organic, but most popular materials are natural materials such as
straw, leaves, pine straw, grass clippings, shrub clippings, garbage, fish
scraps, water hyacinths, etc. A list of materials and what each might contribute
to the compost is given in Table 2 .
In addition, certain of the materials listed as organic fertilizers (for
example, tobacco stems) could also be added.
Use of Compost in the Garden
Since compost is artificial manure, it should be used much as you would manure.
Broadcast it over the entire garden three weeks or more before planting. Or
if you have only a small quantity of compost, it may be mixed into the soil
along each planting furrow or at each hill site. As a minimum, apply it at the
rate of about 25 pounds per 100 square feet, or ¼ pound per square foot. Larger
amounts are even more beneficial, up to 200 lb/100 sq ft. (2 lb/sq ft.).
Caution: If your compost is made from mostly woody materials, it may temporarily
deplete the nitrogen from the soil and plants. Be sure to mix manure with it
when applying.
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Natural and organic materials which yield plant nutrients upon decomposition are
often available for purchase either separately or in combination. These
materials may be applied to the garden separately or combined, used in the
compost pile, or mixed with manure.
Many of the more commonly available materials are listed
in Table 3 along with the nutrients which they
produce. These include both the organic materials derived from plants and
animals, plus the natural deposits of rocks and minerals.
Natural Deposits (Rocks, Sands, Shells, etc.)
Such naturally occurring materials are usually not easily obtained in today's
modern agriculture; however, where available they represent sources of mainly
potash, phosphorus, and lime (calcium and magnesium) for organic gardeners.
Phosphorus ? Rock phosphates are natural
deposits of phosphate in combination with calcium. The material as dug from the
earth is very hard and yields its phosphorus very slowly. When finely ground and
with impurities removed, the powdery material is only slightly soluble in water,
but may be beneficial to plants in subsequent seasons following application. The
reaction of phosphate rock with acids from decaying organic matter in the garden
or compost tend to make the phosphorus available to garden plants. Collodial
phosphate is also available and widely used.
Apply both phosphates at the rate of 2-5 pounds per 100 square feet of garden
soil.
Or, when applying manure or compost, mix at the rate of 2½ pounds phosphate
per 25 pounds manure or compost.
Broadcast the material over the soil surface and work into the topsoil at
least three weeks before planting. Manure or other organic fertilizer should be
added at this time.
Since the materials are so slowly decomposed, sidedressings are seldom
beneficial.
Potash ? Potassium is widely distributed
in nature, occurring in rocks, soils, tissues of plants and animals, and water
of seas and lakes.
In gardening practice, materials such as wood ashes, tobacco stems, wool
suint, seaweed, potash salts, greensand, and ground rock potash are used alone,
in combinations with other materials yielding other nutrients, mixed with
manure, or in compost piles.
Since the potash bearing materials vary so much in composition and rate of
decomposition, specific application rates must be determined for each material
and its combinations.
In general, ground rock potash at 5 pounds per 100 square feet may be
broadcast over the soil surface three weeks prior to planting and spaded in.
Langbeinite (Sul-Po-Mag) is used at 1 lb/100 sq ft.
Micro-nutrients ? An advantage for using
organic materials as fertilizers is that they contain many of the elements also
needed by the plants in addition to N, P, and K (for example, manganese in
manure).
Besides the general amounts of micronutrients found in most organic
materials, certain ones are concentrated into such naturally occurring materials
as gypsum (calcium and sulfur), marl (calcium), dolomite (Calcium and
magnesium), limestone (calcium), basic slag (iron, calcium, manganese and
magnesium), and finely ground borosilicates.
Lime ? Reducing the acidity of the soil
is the primary purpose for using lime in the garden. However, liming materials
also provide nutrients for plant use. Calcium and magnesium are the two elements
most commonly provided by lime. Gypsum is used where more calcium is needed
without raising the pH.
Natural deposits of lime which are an organic gardener might use are
limestone, dolomite, shell, and marl. All these forms must be finely ground to
provide maximum benefit to the soil and plants. Dolomite is preferred due to its
ocntent of both calcium and magnesium.
Lime to sweeten the soil should be applied only when the needs have been
established by a reliable soil test. Under most Florida soil conditions,
applications of 2 to 5 pounds of finely ground dolomitic limestone per 100
square feet usually will be sufficient except on very acid soils.
Apply lime well in advance of the planting date, preferably 2 to 3 months
before the garden is planted. Mix well with the soil and keep moist for best
reaction. Application closer to planting time is permissible, but its benefits
are delayed.
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In irrigating the garden, it is advisable to thoroughly wet the soil once a week
unless sufficient rain falls. Thus, the soil will be moistened throughout the
root zone. Light sprinklings every day merely tend to wet the surface and
encourage shallow root growth. Drip or trickle irrigation is encouraged as a
method for conserving water.
Use of organic materials as soil conditioners and fertilizers tends to
improve the ability of the soil to retain moisture. Also, a good garden mulch
will conserve soil moisture. Please observe all local watering regulations.
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A mulch is any material, usually organic, which is placed on the soil surface
around the plants. Organic materials most commonly used for mulching are
leaves, grass clippings, pine straw, sawdust, and wood shavings. Synthetic
materials, mostly plastic sheeting, have been used quite often in recent years.
Among the benefits of a mulch are (a) conserves soil moisture, (b) conserves
nutrients, (c) reduces soil erosion, (d) reduces crop loss due to nematodes, (e)
reduces weed growth, (f) provides barrier between fruit and soil, thus reducing
soil rot on fruit, and (g) moderates the soil temperature.
Apply mulch before or after seeding or transplanting. Roll back the mulch
with a rake in order to wet the soil beneath when irrigating, for best results.
At the end of the garden season, the mulch (except plastic) may be removed
and composted, or cut into the garden soil. Most mulch is woody and should have
manure or other rich organic fertilizer applied with it when cutting into the
soil.
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The primary purpose of cultivation is to control weeds. Weeds are easy to
control when they are small. Shallow cultivation and hoeing are advised in order
to reduce damage to the root system. A garden mulch, such as pine straw, leaves,
or other material, will help to keep weeds from growing if the mulch is thick
enough to exclude light.
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During periods when infestations of various garden pests are high, control by
natural means becomes very difficult. However, the following practices will help
to reduce losses without use of chemical pesticides.
- Plant resistant varieties.
- Plant seed from disease-free plants.
- Select pest-free transplants.
- For cutworms, place a cardboard of tinfoil collar around plant stems at
ground level.
- Spade garden early so vegetation has time to rot before planting.
- Use a mulch; vegetables touching the soil may rot.
- Clean up crop refuse early.
- Plant as early in the spring as practical.
- Keep out weeds which harbor insects and diseases.
- Summer fallowing (clean cultivation) helps control nematodes.
- Summer flooding, where soil type permits, helps control nematodes.
- Hand-pick insects.
- Water in morning so plants are not wet at night.
- Dispose of severely diseased plants before they contaminate others.
- Some insects, like cabbage worms, may be killed by spraying with natural
preparations such as Bacillus thuringiensis.
- Rotate garden areas.
- Bake transplanting soil in oven at 160°F for 1 hour.
- Crotolaria spectabalis and marigolds, when planted as cover crops,
tend to reduce some kinds of nematodes. The use of marigolds to repel
nematodes from interplanted vegetables is not effective control.
- A good garden mulch tends to reduce damage caused by nematodes.
- Many organic gardeners approve of and use sprays and other preparations
containing naturally occurring materials. Diatomaceous Earth comes from
petrified sea life. Pyrethrin, rotenone, and ryania are examples of natural
poisons from plant parts. These give some control to some insects under
certain conditions.
- Natural predators should be encouraged wherever possible; however,
predators raised in captivity, then released into the garden area are
usually ineffective.
- Insecticidal soaps, made from fatty acids tend to work well for some
insects under average conditions.
- Insect traps, baited with phermone lures, work well in some instances.
Many of these have sticky adhesives to catch insects.
- Solar fumigation is effective in reducing some soil-borne problems such as
nematodes. Refer to "Nematology Plant Protection Pointers", such
as NPPP-17, for details.
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Suitable materials for growing vegetables the organic way are not always easy to
locate. The "conventional" garden supply centers carry many products,
especially seeds and equipment, which may be used by the organic enthusiast.
However, for the difficult-to-find items, the gardener may have to order from
specialty businesses dealing in organic gardening supplies.
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Additional information about organic gardening may be found in Fact
Sheet EES-327 , "Organic Fertilizers and Soil Amendments".
Tables
Back Table 1.