INSTITUTE OF FOOD AND
UNIVERSITY OF FLORIDA
A Vegetable Crops Extension Publication
\-gtable Crops Department. 1255 HSPP* Gaincwsillc. FL 32611" Telcphlonc 392-213
October 11, 1988
I. NOTES OF INTEREST
A. Vegetable Crops Calendar.
B. New Publications.
II. COMMERCIAL VEGETABLES
A. Production of Seedless Watermelons: Part 2.
B. Fresh Produce Is Best Source of Vitamin A for
C. Quality Produce Is Branded Better?
D. Precooling Florida Sweet Corn. Part I.
III. PESTICIDE UPDATE
A. Sethoxydim (Poast) Labelled on Potatoes.
IV. VEGETABLE GARDENING
A. New Publication: Bulletin SP-40, Manual
Vegetables, by James M. Stephens.
SB. Master Composters of Seattle.
." "' Note: Anyone is free to use the information in this
newsletter. Whenever possible, please give credit to the
authors. The purpose of trade names in this publication is
.. /solely for the purpose of providing information and does not
necessarily constitute a recommendation of the product.
The Institute of Food and Agricultural Sciences is an Equal Employment Opportunity Affirmative Action Employer authorized to provide research,
educational information and other services only to individuals and institutions that function without regard to race, color, sex, or national origin.
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS, STATE OF FLORIDA, IFAS, UNIVERSITY OF
FLORIDA, U. S. DEPARTMENT OF AGRICULTURE, AND BOARDS OF COUNTY COMMISSIONERS COOPERATING
Vegetarian October 1988
I. NOTES OF INTEREST
October 27, 1988. Florida Pep-
per Institute. Southwest Florida REC
Immokalee (Contact D.N. Maynard).
October 28-31, 1988. National
Junior Horticultural Assn. Conven-
tion. Hyatt Regency-Oakbrook Hotel,
November 1-3, 1988. Florida
State Hort. Soc. Biscayne Marriot
November 7, 1988. State Master
Gardener Advisory Committee Meeting,
1308 Fifield, University of Florida.
(Contact Kathleen Ruppert).
November 15, 1988. Deadline:
for National Gardening Association
Youth Program Grants. (Contact Jim
November 30, 1988. Ornamental
Field Day. Gulf Coast REC, Bradenton
(Contact Will E. Waters).
March 20-24, 1989. Tour Com-
mercial Harvesting and Handling of
Horticultural Crops. (Contact Steve
June 19-23, 1989. 4-H Horti-
culture Institute. 4-H Camp Ocala
(Contact Jim Stephens).
B. New Publications.
Price, J. F., D. J. Schuster,
and J. B. Kring. Management of the
Sweetpotato Whitefly on Tomato Crops
in South Florida. Bradenton GCREC
Res. Rept. BRA1988-15.
Curcurbit Diseases, A Practical
Guide for Seedsmen, Growers, &
Agricultural Advisors, by Elizabeth
Bernhardt, Jeff Dodson, and Jon
Watterson. Petoseed Co., Inc. P. O.
Box 4206, Saticoy, CA 93004-0206.
Now available! Manual of Minor
Vegetables, Bulletin SP-40, by James
M. Stephens, IFAS, University of
Florida, Gainesville, FL. 1988.
123 pp. FOR SALE ONLY.
An illustrated compilation of
cultural, descriptive and historical
information about a multitude of
"minor," "miscellaneous," or lesser-
The MANUAL is designed to
familiarize the reader with over 100
so-called "minor" vegetables. It
includes 175 illustrations and an
extensive index of scientific and
synonymous common names. A brief
discussion of each vegetable includes
its description, history, climatic
adaptations, cultural requirements,
and common uses, with growing tips
for Florida gardens.
To Order: see article on same
subject in this newsletter, p. 5.
II. COMMERCIAL VEGETABLES
A. Production of Seedless
Watermelons: Part 2.
Refer to the September Vegetar-
ian for information on development of
seedless watermelon hybrids, the need
for and arrangement of pollenizer
rows, and the importance of adequate
bee population for production of
Discussion in this section will
focus on the characteristics of tri-
ploid seed and crop establishment.
J. M. Stephens, Editor
Triploid seed, i.e. seed
resulting from a cross between a
female tetraploid parent and a male
diploid parent, is used for produc-
tion of seedless watermelons. This
seed differs in at least two
morphological characteristics from
common watermelon seed: the triploid
seed coat is considerably thicker and
the embryo is smaller. The
combination of these two factors
usually results in weaker and
perhaps lower germination. Accord-
ingly, use of containerized
transplants for crop establishment is
preferable to field seeding.
In tests conducted at the Gulf
Coast Research and Education Center,
it was found that germination of
seedless watermelon seed was highest
at 82 and 910F. Lower germination
occurred at 730 whereas at 640F,
germination was only 28%. Therefore,
germination temperatures of about 80
are recommended for seedless water-
Because of the thick seedcoats
and relatively weak embryos, seed-
coats sometimes adhere to cotyledons
after the plants have emerged.
Distorted seedlings are produced if
the seedcoats do not split apart
naturally or, with the risk of
breaking the stem, are physically
removed. Seedcoat adherance to
cotyledons can be significantly
reduced by orienting the seed in the
growing mix. Seed placed with the
radicle (pointed) end up at 450 or
900 had a much lower percentage of
cotyledons with adhering seedcoats
compared to those placed horizontally
or with the radicle end down at 450
Results of seedless watermelon
variety trials will be in the Novem-
(Maynard, Vegetarian 88-10)
B. Fresh Produce is Best
Source of Vitamin A for Senior
Elderly Americans should get
their vitamin A from fruits and
vegetables rich in beta carotene --
a nontoxic source, according to a
recent study conducted at the Human
Nutrition Research Center on Aging at
Tufts University in Boston. Senior
citizens who get their vitamin A at
the drug counter may be building up
toxic levels because prolonged daily
use of supplements containing retinyl
esters, the pure form of vitamin A
used in multivitamins, can lead to
low-level toxicity. Retinyl esters
are not toxic themselves but once in
the blood they can be converted into
free retinyl, which is toxic.
In a survey of 562 men and
women over 60, half reported taking
drug counter supplements and several
of the participants who had taken
these preparations daily for more
than 5 years had retinyl ester levels
two to three times normal and showed
early signs of liver damage. Younger
people apparently don't have the same
buildup of retinyl esters, the
Florida produces an abundance
of carrots, squash, tomatoes and
dark-green leafy vegetables which are
rich in vitamin A. Our high popula-
tion of senior citizens would be well
advised to obtain their vitamin A
from these fresh vegetables instead
of the drug counter supplements that
may be "hazardous to their health".
(Gull, Vegetarian 88-10)
G. QUALITY PRODUCE-Is Branded
First impressions are important
but we don't eat impressions. While
eye-catching cartons may be image
enhancers and product appearance may
be great, there are other factors
that determine produce purchases.
Unlike manufactured goods where
quality control can be minutely
regulated, fresh produce is affected
by a multitude of environmental
factors and therefore consistency of
quality is somewhat variable.
Packing by brand name has
implied that the produce is of
superior quality to non-branded or
generic produce. While this may be
the case in certain situations, it is
not universal as perceived by the
customer, according to The Packer's
Fresh Trends 1988. Desirability of
branded produce was based on six
characteristics: taste/ flavor,
quality, appearance, price, size, and
storage life (the first 3 were
slightly more important than the last
3). Of the respondents 60 years of
age & older, 57% felt branded produce
was superior, while 29% of those
between the ages of 18-29 felt
branded produce was better. From an
income level, 54% of respondents in
the lower income level (less than
$10,000) felt branded produce
superior, and 39% of those in the
higher income level ($30,000 or more)
were so inclined. However, the
majority of respondents felt that
markets should carry branded produce.
Origin labeling was not
important to the retail customer as
only 14% indicated it was a concern.
Preferred growing areas were
associated with a particular product,
for example, California avocados,
grapes, lettuce; Georgia onions
(Vidalia); Idaho potatoes; Washington
apples; Florida citrus; and "locally
grown" products of most types.
Various labeling information
may influence customers to purchase
branded produce rather than generic.
Two factors which were most
influential in the purchase of
branded produce were type/variety
information and nutritional
information; the factor of least
importance for influencing purchases
was identification of the grower or
As expected, most branded
produce was associated with various
types of fruit. A vast majority of
the respondents indicated having no
brand preference for vegetables.
Actually, most vegetable displays at
retail do not feature identification
of brand, or label information except
in conjunction with special promotion
or point-of-sale materials which have
been previously supplied.
If Florida vegetable growers
expect to enhance their competitive
position in the marketplace, they
should pack in a container that is
attractive and will appeal to buyers/
handlers and at the same time protect
the contents, and improve the packed
product such that when displayed at
retail the vegetables will have
appearance and quality equivalent or
superior to vegetables from other
(Gull, Vegetarian 88-10)
D. Precooling Florida Sweet
Corn. Part I. Precooling Princi-
Sweet corn ranks among the most
highly perishable of the vegetable
crops. A freshly harvested ear
respires at very high rates under
ambient temperatures, reducing
subsequent storage life in several
ways. First, water from the kernels
and cob is lost through the husk by
transpiration. This causes denting
in the kernels and desiccation and
loss of green color in the husk
leaves. Second, the kernel pericarp
continues to toughen with time.
Third, sugars in the kernels convert
to starches, particularly with
standard cultivars, such as 'Silver
Queen', and the sugary-enhanced
cultivars. However, with greater
acceptance of the shrunken-2
cultivars by the Florida industry,
conversion of sugars to starches has
been greatly reduced when compared to
the other sweet corn types. For
these reasons, the recommended
storage conditions for sweet corn are
32aF (0C) and greater than 95% rela-
tive humidity (Hardenburg, et al.,
1986). This includes the packing-
house, transport and warehousing
Virtually all commercial sweet
corn operations in Florida precool to
some extent; however, in some cases,
the term "precooling" is used quite
loosely. In order to be effective,
precooling must be properly defined.
A working definition of commercial
precooling is the timely removal of
at least 3/4 of the field heat from
a particular crop by a recommended
method. Notice that there are three
components to this definition.
Timeliness: Once the crop is
harvested, field heat must be removed
as quickly as possible to slow
respiration. In the case of sweet
corn the precooling treatment should
be applied within a few hours of
3/4 Cooling: A successful precooling
treatment should remove at least 3/4
of the difference between the initial
pulp temperature and the recommended
storage temperature. The remaining
25% of the field heat should be
removed in the cold room to a final
storage temperature of 320F.
Failure to achieve 3/4 Cooling is one
of the most overlooked aspects of
many cooling operations. This will
be discussed in more detail after the
Recommended Precooling Method: The
precooling method should not
adversely affect the quality of the
crop. Since sweet corn is very
susceptible to water loss, hydro-
cooling has traditionally been the
most common precooling method for
corn packed in wirebound crates.
Vacuum cooling is also used in
conjunction with a water drench. In
more recent years, slush icing has
been used as the sole precooling
treatment. Slush icing (also known
as liquid icing) refers to the
injection of a mixture of crushed ice
and water into an oversized con-
tainer. This method is a variation
of the more traditional method of
package icing, in which crushed ice
is placed over the top layer of a
The ability to achieve 3/4
Cooling is dependent upon three
factors: the amount of time that the
crop is in the precooler, the
temperature of the cooling medium,
and the degree of contact between the
cooling medium and the crop surface.
Since the majority of Florida sweet
corn is hydrocooled, these three
factors affecting precooling
efficiency will be discussed related
Time: The precooling operation
should be scheduled so as to permit
sufficient resident time in the
precooler. When the hydrocooler has
insufficient "throughput" capacity,
the manager may tend to "push the
product through" in order to remain
on schedule with the corn arriving
from the field.
Water Temperature: For maximum
cooling the hydrocooler water should
be held at 32-33oF. The hydrocooler
may not have adequate refrigeration
capacity to be able to maintain this
temperature throughout the day.
Rising water temperatures would
require increasingly longer residence
times to achieve the same amount of
cooling. As a rule, cob temperatures
should be measured before and after
hydrocooling. Water temperature
should also be frequently measured.
The cooling time will also have to be
increased if the incoming cob
temperature rises during the day.
Degree of Water Contact: Water is an
excellent cooling medium in that it
has a high heat capacity. In order
to utilize this capacity, the chilled
water must have intimate contact with
the surfaces of the ears. The
greatest hydrocooling efficiency
occurs with corn in bulk. Hydro-
cooling corn which is packed in
wirebound crates reduces the degree
of water contact; contact is reduced
even further when palletized crates
Consistently high quality sweet
corn can be purchased in distant
markets when precooling is applied in
a timely manner to achieve at least
3/4 Cooling by a method which
Presentation of recent research
results comparing cooling rates of
sweet corn commercially precooled by
hydrocooling, vacuum cooling and
slush ice cooling.
(Sargent, Vegetarian 88-10)
III. PESTICIDE UPDATE
belled on Potatoes.
dim (Poast) La-
Sethoxydim (Poast) has received
a label for the control of grass
weeds in potatoes. Poast controls
actively growing annual grasses at
0.188 Ibai (1 pt.) and perennial
grasses at 0.28 Ibai (1 1/2 pt.) in
5 to 20 gallons of spray per acre.
Use 2 pints of a crop oil concentrate
in the spray mixture. A total of 5
pints per acre may be applied per
season. Do not apply within 30 days
of harvest. Consult the label for
rate for particular grass species and
growth stage for best control.
(Stall, Vegetarian 88-10)
IV. VEGETABLE GARDENING
A. New Publication: Bulletin
SP-40. Manual of Minor Vegetables, by
James M. Stephens.
Florida's mild climate presents
the home gardener with an opportunity
to grow a wide assortment of
vegetables, including not only the
well-known types, but many other
minor varieties. This factor, com-
bined with that of our large popula-
tion of retirees who have both the
time and inclination to grow and
experiment with every type of
vegetable, results in gardens con-
taining a multitude of miscellaneous
Florida is also a national
leader in the production of many
vegetable crops for commercial
purposes. These include 20 to 30
vegetables usually regarded as major
crops. However, quite a few of the
so-called "minor," "miscellaneous,"
or "other crops" vegetables are
seasonally found scattered around the
state in commercial fields.
Information on the major
vegetables is extensive, both from a
state and a national perspective. On
the other hand, much less attention
has been given to the development of
cultural information on the minor
vegetables, particularly with respect
to the adaptability of these crops to
Florida conditions. Therefore, this
handbook represents an attempt to
provide information on the so-called
Although the use of "minor" and
"major" is somewhat arbitrary,
"major" is considered here to include
those vegetables most often found in
home gardens or produced commercially
in Florida. Obviously there will be
an overlapping of these two categor-
ies, with some major vegetables in-
cluded, and numerous miscellaneous
vegetables of very minor importance
Vegetables included here are
not only those adapted to and grown
in Florida, but also many that are
not well-adapted. The potential for
production of a particular vegetable
is discussed briefly in many
instances, particularly in reference
to home use. In fact, the
information is more relevant to home
garden than commercial production.
The information has been drawn
from the author's quarter century of
service to the Florida and national
gardening public as Extension
Vegetable Crops Specialist. It has
been gathered from an array of
publications, both popular and
scientific, and from notes taken at
seminars, workshops, and professional
meetings where these crops were
The vegetables described in
this manual are listed alphabetically
according to a common name in the
order in which they occur in the
bulletin. The manual also lists the
major vegetables that are not
included. Common names are cross-
referenced in the index.
Descriptions of vegetables
provide first a common name followed
by the accepted scientific name,
according to Hortus III and Smith and
Welch (Smith, P. G., and J. E. Welch.
1963. Nomenclature of vegetables and
condiment herbs grown in the United
States. J. Amer. Soc. Hort. Sci.
84:535-547). The text includes other
common and related botanical names,
history, description, climatic
adaptation, and cultural information.
In some cases, a discussion of
harvesting, preparation, marketing,
composition, and uses is included.
A photograph or illustration of
nearly every vegetable occurs with
the text. To supplement these,
additional photographs can be found
in the back of the manual.
To order send a check or money
order in the amount of $3.00 (Florida
residents add 6% sales tax ($.18 per
copy)) to Publications, IFAS Building
664, Gainesville, FL 32611. Make
checks payable to "University of
Florida" (U.S. Banks Only).
(Stephens, Vegetarian 88-10)
B. Master Composters of
It should be of interest to
note the emergence of a gardening
related project (program) in Seattle,
Washington that may have implications
for us here in Florida.
Seattle has begun a "Master
Composters" program, based on the
success of the "Master Gardener"
program. Today, according to Home &
Family, there are 100 accredited
members, ranging from housewives to
book editors and university profes-
sors, who spread the word about home
They go through a 36-hour
training course that includes both
classroom and on-the-job instruction.
Those who successfully complete the
course are given a pitchfork, a
compost thermometer, and a training
manual. Then they are told to go out
and spread the word wherever they can
and to help gardeners make and use
compost in the yard and garden.
To help with the effort, the
city has a major composting demon-
stration site where 16 composting
methods are on display. Their idea
is to show a range of practical
composting options so that homeowners
can choose a system that best suits
their individual lifestyles. Since
the program began in 1985, there have
been over 150 guided tours of the
plots and about 20,000 "how-to"
brochures handed out.
The city's main objective was
the removal of yard waste from the
steady stream of municipal waste. In
support of this objective, the City
of Seattle funded the composting
proposal turned in by a group called
Seattle Tilth Assc.
4649 Sunnyside Ave.
North Seattle, WA 93103
Send $26.00 for their packet that
includes the original proposal, a
training manual, educational plans,
display site plans, outreach
material, and a budget analysis.
(Stephens, Vegetarian 88-10)
More information on the program
can be obtained by writing to:
Prepared by Extension Vegetable
Dr. D. J. Cantliffe
Dr. G. J. Hochmuth
Dr. S. M. Olson
Dr. W. M. Stall
Dr. D. D. Gull
Dr. D. N. Maynard
Dr. S. A. Sargent
Mr. J. M. Stephens
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