FOR EFFICIENT SORGHUM PRODUCTION:
1. Select soils well adapted to crop production.
2. Have soil tested.
3. Apply the recommended kind and amount of limestone.
4. Prepare a good seedbed.
5. Choose hybrids that are well suited for the uses to be
made of the crop.
6. Plant during the season that temperature and soil moisture
conditions are favorable for germination and growth.
7. Apply adequate amounts of fertilizer at the appropriate
8. Keep crop free of weeds.
9. Harvest grain or silage at proper stage of growth.
Cooperative Extension Service
-/ Institute of Food and Agricultural Sciences
University of Florida, Gainesville
K. f t -8I' ,
Select a variety or hybrid adapted to the area
and suited for the intended purpose. If grain is
desired use one of the grain sorghums. For silage
use a sorghum developed for that purpose or one
of the grain sorghums, if high quality silage is
desired. The sorghum-sudan hybrids should be
planted for grazing, green chop or low quality
The use of sorghums in Florida has increased in
recent years. This crop offers a real possibility of
increasing the amount of grain and forage avail-
able to livestock. Sorghum can be grown through-
out the entire state and on all soils now used for
Sorghums can be grouped into three broad
classifications. Grain or combine, sorghums pro-
duce a short stalk with large amounts of grain.
Silage sorghums are those that produce a taller
stalk, more leaves but may produce about as much
total grain as the grain sorghums. The grazing
types are usually sorghum-sudangrass hybrids
and produce essentially no grain, but have the
ability to make very rapid vegetative growth
under favorable conditions.
SOILS AND SEEDBED PREPARATION
Select soils that are considered good agricul-
tural soils in the area where the crop is to be
grown. Sorghums have a wide range of soil
adaptibility, being able to withstand more drought
and more flooding than most cultivated crops
grown in Florida. Most satisfactory growth will
be obtained from those soils with relatively high
natural fertility levels and favorable moisture
Careful preparation of the seedbed is an im-
portant step in sorghum production. Land should
be plowed and/or harrowed to a depth of 5 to 6
inches. Seedbed preparation should destroy weeds,
incorporate lime, if needed, and provide soils con-
ditions favorable for seed germination and rapid
PLANTING AND SEEDING RATE
Sorghums and sorghum-sudan hybrids may be
planted in rows, drilled or broadcast. There will
be little difference in yield of the crop planted by
either of these methods. Row plantings do give
an opportunity for cultivation if this is desirable.
Sorghums, a warm weather croo, should not be '
planted until all danger of frost is past and
the soil is warm. Yields will be reduced by up to
30 percent on plantings made after mid June.
Early planted grain or silage sorghums may make
a second or "ratoon" crop, but yields are often less
than half of the original harvest.
The following Table gives
adapted varieties or hybrids
some of the better
adapted to Florida
Asgrow, Titan R,
ACCO, Sweet Sioux
Asgrow, Grazier A,
DeKalb, Sudax 11,
Frontier, Hidan 39
Pfister, Suchow 35
Seeding rate for the sorghums and sorghum-
sudan hybrids is 8 to 10 pounds of seed per acre
when planted in 30 to 42 inch rows. For broadcast
or drilled plantings, the seeding rate should be
increased by 25 per cent for sorghums and doubled
for sorghum-sudangrass. Regardless of seeding
method, seed should be planted in moist soil and
covered 1 to 2 inches in depth.
LIMING AND FERTILIZATION
Soils should be tested during the fall or winter
to determine the kinds and amounts of lime and
fertilizers needed. Sorghums do best in soils with
a pH of 5.5 to 6.5 and a CaO level of not less than
600 and a MgO level of not less than 100 pounds
per acre. If lime is needed it should be broadcast
and incorporated into the soil during the land
Fertilizers suggested for these crops on mineral
soils are given in Table 2 on page 5.
RECOMMENDED FERTILIZER APPLICATIONS*
Soil-Test Ratio Lbs./A. Ratio No. Lbs./A./App.
Crop P05 K20 N-P205-KO0 N-P0.,-KO, N-P..0-K.O App. N-P,05-K.O
Low 1 -3 -3 32 96 96 N only 3-4 48 0 0
Pearlmillet, Sorghum- High 1 3 2 32 96 64 N only 3-4 48 0 0
Low 1 2- 3 32- 64 -96 N only 3-4 48 -0 -0
High 1 2- 2 32 64 -64 N only 3-4 48 0 -0
Low 1 -3 -3 32 -96 -96 N only 1 96 0 -0
High 1 3 -2 32 96 64 N only 1 96 0 -0
Low 1 2 3 32 -64 96 N only 1 96 0 0
High 1 2 2 32 64 -64 N only 1 96 0 -0
*Supplementary applications should be made to sorghum-sudan hybrids at 3 to 4 weeks after planting and each 4 to 6 weeks thereafter. For grain and forage sorghum.
supplementary fertilizer should be applied when plants are about knee high or at 5 to 6 weeks after planting.
For row plantings, all of the basic application
may be broadcast and plowed down before plant-
ing or applied at planting time in continuous
bands 2 to 3 inches to each side and 2 to 3 inches
below the level of the seed. For drill or broadcast
plantings the basic application should be broad-
cast and disked into the soil ahead of planting,
placing fertilizer close to but not in direct contact
with the seed.
If a second, or "ratoon", crop is to be attempt-
ed, it should be refertilized at about half of the
original rate. The fertilizer should be applied
immediately after the first harvest.
Rates of fertilization should be increased ap-
proximately 50 percent if grain or foliage sor-
ghums are grown on land from which the previous
crop was removed as silage.
HARVESTING, UTILIZATION AND STORAGE
The proper time to harvest sorghums by the
kind, variety and intended use of the crop. These
are described as follows:
Harvesting of grain should not be started until
the heads are well mature and before shattering
of seed. This is indicated by color, hardness and
moisture content of grain. Some hybrids have a
tendency to lodge (break over) and should be
harvested as early as possible.
Direct combining is the most practical method
of harvesting grain sorghum. Adjustments should
be made in the machine to avoid cracking large
amounts of grain.
The moisture content of sorghum grain should
be not more than 12 percent when placed in stor-
age. It will probably be necessary, under Florida
conditions to artificially dry seed before it is
Grain sorghum that is to be fed to livestock
may be stored as high moisture grain in an air
tight silo. Grain to be stored in this manner
should have a moisture content of 24 to 28 per-
The forage sorghums may be fed to livestock
as green chopped forage or made into silage. The
feeding value of this crop is determined, to a
large extent, by the amount of grain that it con-
tains and the maturity of the grain. The nearer
maturity, the greater the amount of carbohydrate
in the grain and consequently the entire forage.
A stubble of 6-8 inches should be left if a
second crop is anticipated. The cut should be
made in such a manner that shattering of the
stubble is avoided and equipment does not run
Sorghum silage may be stored in any type silo
and spoilage will be no greater than for any other
These plants germinate and grow very rapidly.
For all practical purposes, they produce no grain
and consequently only forage that may be grazed
by livestock or fed as green chopped material.
PRUSSIC ACID POISONING
The sorghums and many other species are ca-
pable, under certain conditions, of developing
hydrocyanic acid, also called prussic acid, which is
highly poisonous. This substance develops when
normal growth of the plant has been affected by
drought, cold weather, bruising, wilting or other
causes. Generally as plants mature this danger
decreases. Plants grown on poor soils contain less
of this acid than those on good soil. Fertilization
with nitrogen markedly increase the amount of
this substance. Sorghums grown in Florida have
not poisoned livestock as much as those grown
It is suggested that grazing or green chopping
be delayed until the plants have made considerable
growth. With forage or grain sorghums this would
be in the boot stage of growth. With sorghum-
sudangrass hybrids growth should be about 30
inches in height.
If there is any doubt about prussic acid in the
forage it is suggested that only one or two ani-
mals be permitted to graze or be fed the harvested
forage and that they be carefully observed for
several hours. If no adverse symptoms are seen
it can be assumed that the forage is safe for
Weeds can be a problem in sorghum production.
Careful attention should be given to both mechan-
ical and chemical means of control.
Thorough seedbed preparation and other cul-
tural practices should be used to destroy as many
weeds as possible. Herbicides can be effective in
controlling weeds, however, it is essential that
the proper material be used, at the proper rate
and that it be applied at the most advantageous
Preemergence treatment with propazine is ef-
fective in controlling many weeds. This material
should be used at the rate of 2 pounds per acre
Postemergence treatment using 2,4-D or atra-
zine can be effective in controlling weeds if applied
before the weeds are 2 inches tall. 2,4-D amine
applied at /2 pound per acre is very effective for
annual broadleaf weeds. Atrazine used at 21/
pounds per acre can control most annual grasses
and broadleaf weeds, however, should not be ap-
plied until sorghums are four to six inches tall.
In using chemical weed control materials, read
the label before applying, carefully follow direc-
tion and note precautions.
Sorghum is attacked by many of the insects
commonly associated with corn. Corn earworms,
armyworms, and aphids are very common. Sor-
ghum throughout the Southeast is also infested
by the sorghum midge and the sorghum web-
When sorghum midge is present, an infestation
of one larva per spikelet is sufficient to cause a
loss of grain. Corn earworms, armyworms, and
sorghum webworms eat the ripening grain ker-
nels. Aphids damage young plants, may cause
problems with head emergence, and infestation
prior to harvest results in sticky grain that is
difficult to harvest.
INSECT CONTROL GUIDE
Sorghum webworm carbaryl (Sevin) 80% WP 2 lbs. For best results apply
Corn earworms parathion 4E 1 pt. when larvae are small.
Armyworms toxaphene 8E 1 qt.
parathion 4E plus pt. + li pts.
Sorghum midge diazinon 4E P pt. Apply when 90% of the
methyl parathion 4E % pt. heads have emerged from
carbaryl (Sevin) 809 WP 2t' lbs. the boot and before
blooming. Repeat in 3-
5 days if larvae are
still alive. Destruction
of Johnson grass will
help reduce midge popu-
lations. Leaf damage
may occur on some varieties
when Sevin or methyl
parathion is used.
Aphids malathion 5E 11 pts.
diazinon 4E 1 pt.
parathion 4E % pt.
RESTRICTIONS AND LIMITATIONS
Do not apply within 21 days of harvest for grain.
No time limitations for forage.
Do not apply within 7 days of harvest for grain.
No time limitations for forage.
Do not apply within 7 days of harvest.
Do not apply within 21 days of harvest.
Do not apply within 12 days of harvest or cutting
Do not apply within 28 days of harvest. Do not
apply more than once after heads start to form.
Do not graze dairy animals or animals being
finished for slaughter on treated fields. Do
not ensile treated forage.
Insecticides are poisonous to man and animals.
Handle them with care. Always read the insecti-
cide label carefully and completely before opening
the containers and observe all precautions. Do
not contaminate feed and water. Store insecticides
in the original labeled containers out of reach of
children, pets and livestock and away from food
or feed. Dispose of empty containers promptly
Use of trade names in this publication is solely for the
purpose of providing specific information. It is not a
guarantee or warranty of products named and does not
signify approval to the exclusion of others of suitable
This guide was prepared by D. W. Jones, Associate
Professor in cooperation with G. M. Prine, Associate
Professor, Department of Agronomy, and J. R. Strayer,
Assistant Professor, Department of Entomology and Nem-
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(AcLs of May 8 and June 30.1914)
Cooperative Extension Service, IFAS, nivrsity of Florida
and United States Department of Agriculture, Cooperating
Joe N. Busby, Dean