(Prepared in cooperation with workers of the
Florida Agricultural Experiment Stations)
Production practices are subject to rapid change by
new problems and the practical application of research
results to meet these needs. No attempt is made here
to foresee all the complications possible, but instead to
present the current pertinent facts on sweet potato
production. Experienced growers may have several
modifications of these practices for specific conditions.
For further details on local application of these facts,
contact your County Agricultural Agent.
HARVESTED ACREAGE OF SWEET POTATOES BY
LEADING COUNTIES AND THE STATE, 1945 CENSUS:
Alachua ........... 951
Bradford .......... 308
Escambia .......... 435
Gadsden ........... 993
Hillsborough ....... 304
Holmes ............ 483
Jackson ........... 1,223
Jefferson ......... 1,373
Leon .............. 1,056
Madison ........... 574
Marion ............ 563
Martin ............ 517
Okaloosa .......... 384
Santa Rosa ........ 460
W alton ............ 463
Washington ....... 439
47 + Others........ 4,093
This is the latest breakdown available on county pro-
duction. Preliminary 1950 estimates show an increase
of 26,000 bushels over the 1945 production of 1,024,000
bushels from the acreage shown.
FOUR-SEASONS' YIELD, COSTS AND RETURNS PER
ACRE-LA CROSSE AREA
1945-46 1946-47 1947-48 1948-
ishels per acre...... 93 75 84 63
oduction cost ...... $130 $171 $150 $126
harvesting cost ...... 100 72 70 34
les ............... 410 181 335 227
et return ........... +180 -62 +113 +67
AGRICULTURAL EXTENSION SERVICE
UNIVERSITY OF FLORIDA
Central Florida.. ....
South Florida ......
SEED TO PLANTS
40 to 45 days,
soil at 800 F.
Feb. 15 to Apr. 15
Jan. 15 to Apr. 15
Oct. 1 to Apr. 1
120 to 140 days
150 days or more
Set Draws or
April 1 to June 1
March 1 to June 1
Nov. 15 to May 15
Aug. 1 to Nov. 1
July 1 to Nov. 1
June 15 to Dec. 1
VARIETIES RECOMMENDED COMMERCIALLY
Cliett's Bunch and Unit No. 1 or Copper-Skinned Porto Rico.
PLANT BEDS (electric, manure or flue-heated with soil tem-
perature at 80-85* F.)
11/" or larger in
diameter, No. 1 and
Jumbo size from
vine cuttings or cut
Row space pe
bushel: 35 3
12" to 14"
3%' to 4'
Allow 12 square
feet per bushel.
Cover 112" deep
Plants for 1 Acre:
6 to 7 bushels in 3
SEED FIELD-BEDDED IN ROWS
Patch Size: Seed Required,
: 31' One acre produces Plants for 1 Acre:
vine cuttings for 8 to 10 bushels in 3
s: 6". 10-15 acres pulling
Height: 10" to 14"
Width: 24" to 30"
10,000 to 12,000 (70-
80 plants weigh 1
Best results are obtained by applying fertilizers be-
fore or at the time of planting, in two bands, each 2 to
3 inches below and 3 to 4 inches to the side of the
Pounds Pounds per 100'
Type per Acre with 3/2' Rows
Marl soil ......... 3-8-8 700 5%
Light sandy ...... 3-6-10, 3-8-8 1,000* 8
Dark sandy ....... 4-7-5, 3-8-8 800* 6%
*Sweet potatoes for early market may receive double
(Boron: While thus far no authentic case of borol
deficiency in sweet potatoes has been reported ii
Florida, other states have claimed response to ap
plications of around 5 pounds borax per acre. Witl
this element the margin between deficiency and tox
city is narrow.)
DISEASES AND CONTROLS
Seed Selection: Many diseases may be reduced b:
growing enough seed from vine cuttings to produce,
next year's seed supply. Select hills at digging tim
which are free from disease, have desirable variety
characteristics and have at least four or five No.
potatoes per hill. Seed stock should be free of interns
cork, a disease for which there is no other know
Plant Bed Site: Locate the bed where sweet potato
or tobacco have never been grown or have not bee:
grown within three years. If permanent beds are to b
used, remove soil to a depth of 12 inches, drench th
bed and frame with a solution of 1 pint of formaldehyd
per 15 gallons of water, then replace with new soil.
Semesan Bel: 1 pound to 71/2 to 8 gallons wate
for one minute; bed, or dry in the shade.
Mercuric Chloride: Dissolve 4 ounces in 1 gallo:
hot water and add to 31 gallons of cold water i:
a clean wooden container; dip for 8 to 10 minute
and bed. (After treating 10 bushels add 1 quar
of stock solution, 1/2 ounce mercuric chloride pe
quart water, and add water to 32-gallon mar
on container. Repeat for every additional 1
bushels and discard for fresh solution after 5
Spergon: 1 pound wettable in 5 gallons water; di
(in and right out), drain and bed.
In General-Dip to soil line (do not wet leaves) i
semesan bel, 1 pound per 10 gallons water.
Stem Rot or Wilt-Dip base of stem and plant root
or lower end of vine cutting in wettable spergon solid
tion, 1 pound to 8 gallons water.
Scurf-Dip base of stem and plant roots in fermat
solution, 1 pound to 5 gallons water.
INSECTS AND CONTROLS
Gold bugs-5% DDT.
Grasshoppers-5% Chlordane; 10% Toxaphene.
Leaf-eating Caterpillars-5% DDT; 5% Chlordane;
Sweet Potato Weevil-Sanitation; certified or weevil-
White-fringed Beetle-Adherence to quarantine. It
has been reported that 5 pounds technical DDT per
acre, mixed into the soil, prevents breeding of this in-
ect for 5 years.
CURING AND STORAGE
Tightly built barns can be used: A 16' x 16' barn of
average height stores 1,000 bushels. Allow 2%
cubic feet per bushel basket.
Do not wash sweet potatoes before curing and
Clean and fumigate storage house and any used con-
tainers. Rat-proofing measures are in order.
Curing takes place best at 85' F. and high humid-
ity (85%). Controlled ventilation is necessary.
Curing is completed when sprouting starts mid-
way from the floor to the top of the stack, nor-
mally after a period of 10 to 14 days.
Storage temperatures should be maintained at 550
F. and never allowed below 500 F. If soft rot be-
comes excessive during storage the temperature
should be maintained at 750 F. until the potatoes
are dried out.
COOPERATIVE EXTENSION WORK IN AGRICULTURE
AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida
Florida State University
And United States Department of Agriculture, Cooperating
H. G. Clayton, Director