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or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
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site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
Gulf Coast Research
and Education Centeir',
,,JAYS\ w 2 0 99w
InnIjL ,rtS of Florida
5007 60th St. E., Bradenton, Florida 34203-9324
SUNIVERSITY OF Gulf Coast Research and
FLO R IDA Education Center
5007 60th Street East
Institute of Food and Agricultural Sciences Bradenton, FL 34203
GCREC Research Report BRA1994-9 (April)
SPINACH VARIETY EVALUATIONS
Donald N. Maynard'
Spinach, (Spinacia oleraceae L.) is a fast-growing, cool-season, annual vegetable
of relatively limited importance in the United States. In 1993, fresh-market
spinach was grown on 21,800 acres which produced 2.7 million cwt of spinach for
an average yield of 131 cwt/acre. The value per cwt was $23.20 and the total
U.S. crop was worth $62.6 million. California produced over half of the U.S.
spinach crop (Vegetables, 1993 Summary).
In the mid-1960's, more than 2500 acres of spinach were grown on organic soils
in central Florida (Florida Agricultural Statistics, Vegetable Summary, 1967).
Spinach production in Florida for processing was a flourishing industry until the
processing plants closed.Current acreage is estimated to be about 200 statewide.
In an earlier trial, based on yield and growth habit, 'A&C #30' was the most
outstanding smooth-leaf entry, 'Gladiator' and 'Chinook II' were the most
outstanding semi-savoy leaf entries, and 'Hybrid 612' and 'Ambassador' were the
most outstanding savoy-leaf entries (Maynard, 1991).
This trial was initiated because of grower interest in spinach as an alternative
crop for winter production.
Materials and Methods
Soil in the experimental area was sampled before fertilization and analyzed by
the IFAS Extension Soil Testing Laboratory (Hanlon and DeVore, 1989): pH = 7.2,
Mehlich I extractable P = 36, K = 28, Mg = 136, Ca = 940, Zn = 2.8, Cu = 1.3, and
Mn = 2.5 ppm.
The EauGallie fine sand was prepared in early January by incorporating 4 Ibs 18-
0-25 and 4 Ibs 18-6-12 (Osmocote) [1.4-0.2-1.5 lb N-P,20-K20 per 100 linear bed
feet (Ibf) or 120-17-130 lb N-P20O-K0O/acre]. The final beds were 32 in. wide
and 8 in. high and were spaced on 5 ft centers with six beds between seepage
irrigation/drainage ditches which were on 41 ft. centers.
Seeds of 31 hybrid spinach entries (Table 1) were planted in three rows 8 in.
apart on the bed with a Model 1001B Earthway precision seeder using the spinach
'Professor and Extension Vegetable Specialist.
seed plate on 12 January 1994. Each plot was 10 ft long with replicated entries
repeated three times in a randomized complete block design and observational
entries grown in single plots. The spinach was thinned periodically to attain
an in-row spacing of approximately 3 in. Weeds in the bed were hoed or hand
pulled and row middles were cultivated. Additional fertilizer, 5.7 lb 6-6-6/100
Ibf, was sidedressed on 24 January and 17 February 1994. One application of
Bacillus thuringiensis was made for worm control.
Time of harvest was judged subjectively according to plant size. Plants were
harvested during the period between 3 and 10 March by cutting at the base and
then counted and weighed. Where appropriate, the resulting data were subjected
to analysis of variance and mean separation was by Duncan's multiple range test.
Results and Discussion
Weather during the experimental period (Table 2) deviated somewhat from the 1954-
92 averages at the Gulf Coast Research & Education Center (Stanley, 1993).
January average minimum temperatures and February temperatures were considerably
above average. Rainfall was less than average throughout the production period.
Leaf form (Table 1) of the spinach entries in this trial included three smooth
leaf, 18 semi-savoy leaf, and ten savoy leaf types according to detailed field
assessments made immediately before harvest. These designations agree fairly
well to those provided by the seed sources in their variety descriptions. As a
broad generalization, smooth-leaf types are used for processing, savoy-leaf types
are used for fresh market, and semi-savoy leaf types may be used for either
processing or fresh market. However, local market demand may favor production
of one type over the others.
Growth habit (Table 1) of the spinach entries in this trial included eight
prostrate types, 17 semi-erect types, and six upright types. These designations
generally agreed with those included in the variety descriptions provided by the
seed sources. Generally those entries with an upright or semi-erect growth habit
provide greater ease of harvest than those entries with a prostrate growth habit.
Also, the upright types provide the advantages of being cleaner because of less
soil contact and avoiding the possibility of being infested by soil-borne
Although plant populations were thought to be standardized by thinning, there was
some variation among entries (Table 3). Populations in the replicated trial
ranged from 64.5 for XPH 1615 to 94.7 thousand plants/acre for 'Seven R' and from
67.1 for AX 993 to 96.7 thousand plants/acre for AX 293 in the observational
trial. There did not appear to be a direct relationship between population and
yield suggesting growth compensation where populations were lower. Populations
in an earlier trial (Maynard, 1991) ranged from 35.6 to 55.4 thousand plants/acre
where two rows per bed were planted.
Spinach yields (Table 3) in the replicated trial ranged from 39.7 for SP 3-16 to
690 25-lb bushels/acre for 'Gladiator'. Only one other entry, 'Ambassador' had
yields similar to those of 'Gladiator', whereas six other entries had yields
similar to those of SP 3-16. In the observational trial, yields ranged from 233
for AX 993 to 686 25-lb bushels for AX 1393. In the 1991 trial (Maynard, 1991),
yields ranged from 142 to 222 25-lb bushels/acre. The higher yields obtained in
1994 are attributed primarily to the higher plant population obtained with three
lines per bed compared to two lines per bed in 1991. 'Gladiator' and
'Ambassador' were among the highest yielding varieties in 1991 and in 1994.
The only Florida yields for comparison are those reported for processing spinach
in the 1959-67 period (Florida Agricultural Statistics, Vegetable Summary, 1967)
which were equivalent to 432 bushels/acre. Average U.S. fresh market spinach
yields for reporting states ranged from 160 bushels/acre in Virginia to 840
bushels/acre in California in 1993. The national average yield for six reporting
states was 524 bushels/acre (Vegetables, 1993 Summary, 1994).
The average yield of the smooth-leaf varieties in this trial was 490
bushels/acre, semi-savoy varieties had an average yield of 524 bushels/acre, and
the highest yields, 542 bushels/acre, were from the savoy-leaf varieties. These
yields parallel observations of plant and leaf size made at harvest.
From the results obtained in the replicated trial, based on yield and growth
habit, 'Regency' was the most outstanding smooth-leaf entry, 'Gladiator' was the
most outstanding semi-savoy leaf entry and 'Ambassador' was the most outstanding
The information contained in this report is a summary of experimental results and
should not be used as recommendations for crop production. Where trade names are
used, no discrimination is intended and no endorsement is implied.
Florida Agricultural Statistics Vegetable Summary. 1967. Florida Crop &
Livestock Reporting Service, Orlando.
Hanlon, E. A. and J. M. Devore. 1989. IFAS extension soil testing laboratory
chemical procedures and training manual. Fla. Coop. Ext. Circ. 812.
Maynard, D. N. 1991. Spinach variety evaluation, winter 1991. GCREC Res. Rept.
Stanley, C. D. 1993. Temperature and rainfall report for 1992. GCREC Res.
Vegetables. 1993 Summary. 1994.
U.S.Dept. Agr. Vg 1-2.
Table 1. Spinach entries, leaf form, growth habit, and seed source.
Entry Leaf Form Growth Habit Seed Source
Ambassador Savoy Upright Asgrow
Fallgreen Semi-Savoy Upright Asgrow
Gladiator Semi-Savoy Upright Asgrow
Grandstand Semi-Savoy Semi-Erect Asgrow
Kent Savoy Semi-Erect Asgrow
Meridian Semi-Savoy Semi-Erect Asgrow
Packer Savoy Semi-Erect Asgrow
Regency Smooth Upright Asgrow
Seven R Semi-Savoy Upright Asgrow
SP 3-11 Semi-Savoy Prostrate Rogers NK
SP 3-12 Smooth Prostrate Rogers NK
SP 3-16 Semi-Savoy Prostrate Rogers NK
XPH 1615 Smooth Upright Asgrow
AX 193 Semi-Savoy Semi-Erect Asgrow
AX 293 Semi-Savoy Semi-Erect Asgrow
AX 393 Semi-Savoy Semi-Erect Asgrow
AX 493 Semi-Savoy Semi-Erect Asgrow
AX 593 Semi-Savoy Semi-Erect Asgrow
AX 693 Semi-Savoy Prostrate Asgrow
AX 793 Semi-Savoy Prostrate Asgrow
AX 993 Semi-Savoy Semi-Erect Asgrow
AX 1093 Semi-Savoy Prostrate Asgrow
AX 1193 Savoy Prostrate Asgrow
AX 1293 Semi-Savoy Prostrate Asgrow
AX 1393 Savoy Semi-Erect Asgrow
AX 1493 Savoy Semi-Erect Asgrow
AX 1593 Savoy Semi-Erect Asgrow
AX 1693 Savoy Semi-Erect Asgrow
AX 1793 Savoy Semi-Erect Asgrow
AX 28393 Savoy Semi-Erect Asgrow
AX 45193 Semi-Savoy Semi-Erect Asgrow
Table 2. Mean temperature and rainfall at the Gulf Coast Research &
Education Center from 12 January to 10 March 1994 and 1954-1992
monthly averages (Stanley, 1993).
Average Daily Temperature (F)
1994 1954-1992 avq Rainfall (in.)
Month (date)' Max Min Max Min 1994 1954-1992 avq
January (12-31) 73 54 72 49 1.95 2.57
February (1-28) 78 58 74 52 0.75 3.22
March (1-10) 77 56 77 55 1.86 3.40
'1994 data are for the dates shown, 38-year averages are for the entire
Table 3. Spinach plant populations and yields. Winter 1994.
Plant Population Yields Per Acre1
Entry (x 1000) (25-lb bushels)
Gladiator 84.2 ab2 690 a
Ambassador 85.1 ab 623 ab
Regency 74.3 b-d 588 b
Grandstand 81.6 bc 578 b
Meridian 78.7 bc 565 b
Fallgreen 84.8 ab 544 bc
Kent 81.0 bc 473 cd
XPH 1615 64.5 d 457 cd
SP 3-11 70.0 cd 443 d
SP 3-12 74.1 b-d 425 d
Packer 79.6 bc 419 d
Seven R 94.7 a 416 d
SP 3-16 68.8 cd 397 d
AX 1393 80.2 686
AX 293 96.7 656
AX 393 95.0 616
AX 593 91.5 612
AX 1693 91.5 612
AX 793 82.8 586
AX 1193 73.2 586
AX 193 88.9 577
AX 993 91.5 577
AX 493 88.9 574
AX 28393 99.3 568
AX 1493 74.9 544
AX 1293 83.6 511
AX 1593 87.1 456
AX 1793 82.8 455
AX 45193 95.8 446
AX 1093 75.8 362
AX 693 87.1 280
AX 993 67.1 233
'Acre = 8712 lbf.
2Mean separation in replicated entry columns by Duncan's multiple range
test, 5% level.
The Gulf Coast Research and Education Center
The Gulf Coast Research and Education Center is
a unit of the Institute of Food and Agricultural Sci-
ences, University of Florida. The Research Center
originated in the fall of 1925 as the Tomato
Disease Laboratory with the primary objective of
developing control procedures for an epidemic out-
break of nailhead spot of tomato. Research was ex-
panded in subsequent years to include study of sev-
eral other tomato diseases.
In 1937, new research facilities were established
in the town of Manatee, and the Center scope was
enlarged to include horticultural, entomological, and
soil science studies of several vegetable crops. The
ornamental program was a natural addition to the
Center's responsibilities because of the emerging in-
dustry in the area in the early 1940's.
The Center's current location was established in
1965 where a comprehensive research and extension
program on vegetable crops and ornamental plants is
conducted. Three state extension specialists posi-
tions, 16 state research scientists, and two grant
supported scientists from various disciplines of
training participate in all phases of vegetable and
ornamental horticultural programs. This interdisci-
plinary team approach, combining several research
disciplines and a wide range of industry and faculty
contacts, often is more productive than could be ac-
complished with limited investments in independent
The Center's primary mission is to develop new
and expand existing knowledge and technology, and
to disseminate new scientific knowledge in Florida, so
that agriculture remains efficient and economically
The secondary mission of the Center is to assist
the Cooperative Extension Service, IFAS campus
departments, in which Center faculty hold appropri-
ate liaison appointments, and other research centers
in extension, educational training, and cooperative
research programs for the benefit of Florida's pro-
ducers, students, and citizens.
Program areas of emphasis include: (1) genetics,
breeding, and variety development and evaluation;
(2) biological, chemical, and mechanical pest manage-
ment in entomology, plant pathology, nematology,
bacteriology, virology, and weed science; (3) produc-
tion efficiency, culture, management, and counteract-
ing environmental stress; (4) water management and
natural resource protection; (5) post-harvest physiol-
ogy, harvesting, handling and food quality of horti-
cultural crops; (6) technical support and assistance to
the Florida Cooperative Extension Service; and (7)
advancement of fundamental knowledge of disciplines
represented by faculty and (8) directing graduate
student training and teaching special undergraduate
" The Institute of Food and Agricultural Sciences,
University of Florida.
i A statewide organization dedicated to teaching,
research and extension.
" Faculty located in Gainesville and at 13 research
and education centers, 67 county extension
offices and four demonstration units throughout
" A partnership in food and agriculture, and natural
and renewable resource research and education,
funded by state, federal and local government,
and by gifts and grants from individuals, founda-
tions, government and industry.
" An organization whose mission is:
Educating students in the food, agricultural,
and related sciences and natural resources.
Strengthening Florida's diverse food and
agricultural industry and its environment
Enhancing for all Floridians, the application
of research and knowledge to improve the
quality of life statewide through IFAS exten-