Ajay Agri
Ajay Agri
Ajay Agri
Corn is fast-growing and must have ample space to spread roots, stalks and leaves. Corn
stalks, with leaves and ears, typically grow 5 to 10 feet high, depending on the hybrid,
and spread 2 to 4 feet wide. Plants require full sunlight to grow, the space available in
your garden needs to allow for that. Because corn is pollinated by wind, planting seeds in
short rows encourages ear and kernel growth; poor pollination results in stunted corn
ears.
Seed Spacing
Large gardens are optimal for growing sweet corn in blocks or rows with 36 to 42 inches
between them. Two or three seeds are planted 8 to 15 inches apart, depending on the
variety. Sweet corn may also be planted in hills of four or five seeds, about 3 inches
apart, with hills spaced 30 inches apart and 30 to 36 inches between rows of hills. If more
than one kernel per hill germinates, the weaker seedlings are thinned out. Smaller
gardens can accommodate sweet corn too, notes University of Tennessee Extension, if
plots contain moist, organic soil. Kernels are planted about 12 inches apart in double
rows 30 to 42 inches apart.
Most of the trouble gardeners have with corn is easily controlled. Diseases aren't
much of a problem, and insects can easily be kept in check. Birds and four-footed
visitors who want to share your corn harvest can be kept out with any number of
scare-off devices and fences. Prevention can be 100 percent of the cure. If you sow
your corn in well drained soil that has balanced nutrient levels, you're on the road to
having healthy plants. Healthy plants can withstand nibbling or insect damage better
than weakened ones. In many cases, a crop that's healthy will often be spared
disease and insect attack altogether.
A very important step you can take for disease-free corn is to clean up all the
cornstalks as soon as the harvest is over. Till healthy cornstalks into the soil as
additional organic matter, or, if you prefer, shred, compost or simply discard them.
Dealing with old cornstalks will prevent many diseases and insects from
overwintering, which is crucial to the health of crops grown in future seasons.
Stewart's Bacterial Wilt can affect sweet corn at any stage, but is most harmful to young
plants. It causes dwarfing and wilting of the plants, and the tassels often develop early and
die without completing pollination. Leaves develop yellow-brown streaks and wavy edges.
The leaves of young plants may dry out, and the stem eventually dies. This wilt is often
characterized by a yellow slime on the inner husks and in the stem. Bacteria overwinter in
the gut of the corn flea beetle. This disease is prevalent after a mild winter, when more
disease-carrying flea beetles have survived. To prevent an outbreak, clean up all crop
residues, rotate your corn crop each year, plant resistant varieties and control corn flea
beetles.
Corn Smut is caused by a soil fungus, and can strike corn anywhere it's grown. Smut looks
awful, but it's not a disastrous condition. Smut is edible and actually is sought after by
gourmet chefs. In the early stages of the infection, grayish white, spongy growths called
"galls" usually appear on the corn ear or tassel. As these galls ripen, they turn black and
eventually burst open, releasing powdery spores that spread the smut. The disease thrives
in hot, dry weather and often infects weak or injured plants first. To prevent, rotate crops, and
if you notice any galls, pick them and burn them before they blacken and burst. This will halt
the smut's spread and is often all it takes to keep the disease in check from one season to
the next.
Corn earworm is also known as the tomato fruitworm or cotton bollworm. This 1- to 2-inchlong caterpillar ranges from light green to purplish brown. Moths lay eggs on corn plants in
early summer and larvae feed first on the silks, then on the kernels at the tip of each ear.
The insect can prevent pollination, and it opens kernels to fungus invasion. To discourage
this pest, select varieties with tightly closed husks. Earworms can be controlled somewhat by
squirting mineral oil into each ear after silks have started to dry, using half a medicine
dropper per ear. You can also spray the plant and silks with Bt. If earworm damage occurs,
clip off the tip of the ear and any affected kernels. The rest of the ear should be fine to eat.
Corn Root Aphids are tiny, light green insects that feed on corn roots, causing the plants to
be stunted and yellowed. The aphids overwinter in the nests of cornfield ants. The best way
to control this pest is to plow the garden in the fall, destroying ant nests. Corn Flea Beetles
are small but dangerous. Only 1/16th of an inch long, these jumping black beetles chew corn
foliage and transmit Stewart's bacterial wilt. The pests abound during cool, wet periods and
after mild winters. They hibernate in weeds and plant debris over the winter, so keep the
garden and surrounding areas clean. Many of the later-maturing white corn varieties are
resistant to wilt. To repel flea beetles, sprinkle a light dusting of wood ash over plants and
soil.
The primary weed control strategies for organic systems are cultural and
mechanical, focusing on prevention, crop rotation, crop competition, and
cultivation.
To plan an effective weed management program in organic systems, you
should consider historical pest problems, soil management, crop rotation,
machinery, markets, weather, and time and labor. Adjusting weed control
strategies based on these factors and observing and avoiding potential
threats will help you stay ahead of weed problems.
Prevention
Prevention focuses on keeping new weeds out and preventing the further
spread of weed seed or perennial plant parts. Stopping the addition or
introduction of weed seed to the soil can be particularly critical for
successful weed management.
Understanding weed biology is an important component in developing a
preventive approach. Weed species have strengths and weaknesses that
make them vulnerable or resilient at different stages in their life cycle.
Therefore, proper identification and knowledge of weed life cycle and
reproduction and spread are important factors for developing
management strategies. For example, disking or field cultivating a
creeping perennial such as quackgrass or hedge bindweed in the spring
may make the problem worse by spreading underground rhizomes or
other vegetative structures.
Some preventive tactics can be classified as sanitation: removing or
destroying weeds in fields or near fields before they flower and release
weed seed. Weed seeds can live for a number of years, depending on the
species and whether the seed is exposed or buried beneath the soil
surface. If necessary, weeds may need to be removed from the field by
hand before they produce seed. Weeds can also be introduced into fields
through manure, compost, hay, straw, animal feed, contaminated crop
seed, or other materials. Whenever you plant, apply, or drive something
in a field, make an effort to learn whether weed seeds are present and
weigh the benefits against potential risks.
the corn is too tall and the soybean canopy closes the rows. Organic corn
and soybeans generally require one to three cultivations depending on
weed species, severity, and rainfall. Cultivation works best when
performed during the heat of the day in bright sunlight; weeds quickly
desiccate and die under these conditions. Rainfall shortly after cultivation
or wet cloddy soils at or following cultivation may allow weeds to recover
and survive. Hand-pulling escaped weeds will help ensure maximum crop
yield and prevent weed seed production, which can affect future weed
problems.
Mowing may also play a critical role in managing weeds in forage crops or
noncrop areas. Repeated mowing reduces weed competitive ability,
depletes carbohydrate reserves in the roots, and prevents seed
production. Some weeds, mowed when they are young, are readily
consumed by livestock. Mowing can kill or suppress annual and biennial
weeds. Mowing can also suppress perennials and help restrict their
spread. A single mowing will not satisfactorily control most weeds;
however, mowing three or four times per year over several years can
greatly reduce and occasionally eliminate certain weeds, including Canada
thistle. Also, mow along fences and borders to help prevent the
introduction of new weed seeds. Regular mowing helps prevent weeds
from establishing, spreading, and competing with desirable forage crops.
Herbicides
Chemical weed control is generally not allowed in organic crop production
systems. The USDA National Organic Program (NOP) rule does allow
certain nonsynthetic soap-based herbicides for use in farmstead
maintenance (roadways, ditches, right-of-ways, building perimeters) and
in ornamental crops. In addition, several products that contain natural or
nonsynthetic ingredients are classified as Allowed or Regulated by the
Organic Materials Review Institute (OMRI). Regulated substances are
listed with a restriction on the USDA National List or in the NOP rule. The
OMRI listing does not imply product approval by any federal or state
government agency. It is the user's responsibility to determine the
compliance of a particular product.
Corn gluten meal is sold as a preemergence herbicide in some production
systems. However, because of the volume of product necessary and the
associated cost, corn gluten meal is generally not practical for agronomic
crop production systems. In addition, the need for and use of corn gluten
for weed control must be explained in the Organic System Plan and it
must not be derived from genetically engineered sources. To learn more
about corn gluten, visit the corn gluten meal research Web page at Iowa
State University.
The nonsynthetic postemergence herbicides contain plant-based
ingredients, including eugenol (clove oil), garlic, and citric acid, and act as
nonselective contact-type herbicides. They will injure or kill all vegetation
they come in contact with. The need for the use of herbicides derived
from plant or animal sources should be explained in your Organic System
Plan, and you must obtain permission from your organic certifying
agencies to use these materials. Acetic acid or vinegar is an ingredient in
a number of products, but we believe it is not currently approved as an
herbicide for organic crop production systems. Additional products and
ingredients are currently under review.
Nonsynthetic adjuvants (such as surfactants and wetting agents) are
allowed unless explicitly prohibited. All synthetic adjuvants are prohibited,
which includes most adjuvant products on the market. However, a number
of plant-based adjuvants are available. These are often derivatives of pine
resin (Nu-Film P), yucca (Natural Wet), or other plant-based substances.
Some products contain acidifying agents and other ingredients touted to
enhance pesticide or nutrient uptake. Check with your organic certifier to
find out if these additives are allowed.
The following table contains some herbicides listed by OMRI at the time of
printing. Some of these products already include surfactant-type
adjuvants in their formulation. Penn State does not assure the
effectiveness or allowance of any of these products.
Growing corn (Zea mays) can be a money-saving, rewarding experience. This warmseason vegetable can thrive in gardens within U.S. Department of Agriculture plant
hardiness zones 8 through 10 where it's ideally started during the months of April
through July, when the soil has reached a temperature of at least 50 degrees Fahrenheit.
Neglecting to prep your soil before starting your seeds can affect growth and result in a
disappointing harvest. To avoid this, provide your corn with well-drained, rich soil, and
about 65 to 95 days after planting, you'll be rewarded with a plentiful harvest.
1
Perform a soil test to determine the pH of the soil in your garden. Test the soil about one
year before planting, because soil amendments take time to blend with the existing soil.
A pH range of 6.0 to 6.5 is ideal for growing corn. Amend the soil based on the test
results. To raise the pH, work limestone into the top 7 inches of soil, and to lower it, till
sulfur into the soil. To determine the exact amendment amount, use the information
provided with the soil pH test kit or consult the Cooperative Extension Service that serves
your area.
2
Cultivate the soil in a sunny part of the garden. Use a spade for a smaller garden and a
rototiller for a large plot. Loosen the soil to a depth of 6 inches, pulverize clumps and
remove weeds and rocks during the process.
3
Incorporate a 2- to 4-inch layer of compost in the soil to improve soil moisture retention
and nutrients.
4
Work fertilizer into the soil according to the result of your pH test. Alternatively,
incorporate a 12-12-12 fertilizer at the rate of 4 pounds per 100 square feet. Late in the
growing season, when the plants are about 2 feet tall, side-dress with a high-nitrogen
fertilizer.
5
Rake the soil to level it before sowing your seeds.