Vegetarian Newsletter

A Vegetable Crops Extension Publication
University of Florida
Institute of Food and Agricultural Sciences
Cooperative Extension Service
Vegetarian 01-06
June 2001

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VEGETABLE CROPS CALENDAR

COMMERCIAL VEGETABLES

• Web-based Sources of Information for Greenhouse Production of Vegetables
• Sweet Onion Variety Trial, Spring 2001
• Vegetable Section Program - FSHS Annual Meeting
• Postharvest Handling Considerations for Greenhouse-Grown Beit Alpha Cucumbers

VEGETABLE GARDENING

• Heirloom Tomato Varieties for Florida

List of Extension Vegetable Crops Specialists

Related Links

(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.)



Florida State Horticulture Meeting - June 10-12 - Hutchinson Island Marriott Beach Resort and Marina, Stuart, Florida.

American Society for Horticultural Sciences Annual Meeting - July 22-25 - Sacramento, CA.

Florida Tomato Institute - Sept. 5 - Naples, FL.

Florida Agriculture Extension Professionals Meeting - Sept. 10-14.

FACTS Meeting - Oct. 2-3 - Lakeland, FL.

2001 Florida Postharvest Horticulture Institute at FACTS - Oct. 2-3 - Lakeland, FL. Contact Steve Sargent, 352-392-1928 x215, sasa@mail.ifas.ufl.edu. This year's topic, "Sanitation and Food Safety: Protecting Produce and People" will feature Dr. Jim Gorny, Technical Director, International Fresh-cut Processors Association, and UF/IFAS extension specialists in lecture and hands-on/demonstration formats.

Cucurbitaceae 2002 - December 8-12, 2002 - Naples Beach and Golf Club, Naples, FL. Contact Donald N. Maynard at (941)751-7636 x239 or dnma@mail.ifas.ufl.edu.



Web-based Sources of Information for Greenhouse Production of Vegetables

Commercial production of vegetables in greenhouses or shade houses (protected agriculture) is increasing in Florida. The most commonly produced vegetables are tomatoes, European cucumbers, peppers and lettuce but there are also commercial operations growing strawberries, squash, and herbs. Operations range from 30 acres to single bay houses with a variety of types of structures and production methods. A diversity of information is necessary to ensure economically successful production.

Following is an annotated list of web sites relating to planning, building and producing vegetables in greenhouses. As new sites appear continually, this is not intended as an exhaustive list. The state of origin for the information is listed so that it can be viewed in its environmental context.

Florida Greenhouse Production Information

Protected Agriculture page from the Horticultural Sciences Department
http://www.hos.ufl.edu/ProtectedAg/

North Florida Research and Education Center webpage on greenhouse and hydroponic production http://nfrec-sv.ifas.ufl.edu/gh_&_hydroponics.htm

EDIS publications (http://edis.ifas.ufl.edu) include:

Nutrient Solution Formulation for Hydroponic (NFT and Rockwool) Tomatoes in Florida
Design Suggestions and Greenhouse Management for Vegetable Production in Perlite and Rockwool Media in Florida
Florida Greenhouse Design
Greenhouse Ventilation
Heating Greenhouses
Fans for Greenhouses
Maintenance Guide for Greenhouse Ventilation, Evaporative Cooling and Heating Systems
Computerized Greenhouse Environmental Controls
Disease Diagnosis and Control in Greenhouse Vegetables
Weed Management in Enclosed Greenhouses

Business Plans

Creating a master plan for a greenhouse operation (NJ)
http://www.rce.rutgers.edu/pubs/pdfs/e221.pdf

Basic questions to ask when starting a greenhouse business (AR) http://www.uaex.edu/Other_Areas/publications/PDF/FSA-6051.pdf

Estimating income potential of a greenhouse operation (AR) http://www.uaex.edu/Other_Areas/publications/PDF/FSA-6052.pdf

Detailed overview of considerations in starting a greenhouse business (AL) http://www.aces.edu/department/extcomm/publications/anr/ANR-691/pdf/anr-691.pdf

Marketing

Evaluating a marketing plan (TX)
http://aggie-horticulture.tamu.edu/greenhouse/econ/chmkt.html

Greenhouse Structures

Considerations in building a greenhouse (WV)
http://www.wvu.edu/~agexten/hortcult/greenhou/building.htm http://www.wvu.edu/~agexten/hortcult/greenhou/grencons.htm

Greenhouse Coverings

Choosing a covering material based on light transmission (NJ)
http://aesop.rutgers.edu/~ccea/gh-cover.pdf

Environmental Control for Greenhouses

Overview of factors relating to environmental control (MS)
http://msucares.com/pubs/pub1879.htm\

Water and Nutrient Management

Greenhouse management handbook (TX)
http://aggie-horticulture.tamu.edu/greenhouse/guides/green/green.html

Overview on irrigation and fertilization (NC)
http://www.ces.ncsu.edu/depts/hort/greenhouse_veg/waterfert.html

Water quality measurement for greenhouse production (AL) http://www.aces.edu/department/extcomm/publications/anr/anr-1158/anr-1158.html

Spreadsheet for fertilizer injection (MS)
http://www.mafes.msstate.edu/pubs/bulletins/b1003.htm

Growing Media

Descriptions of media available and their characteristics (written for nursery crops but applicable to greenhouse vegetables) (AR)
http://www.uaex.edu/Other_Areas/publications/PDF/FSA-6097.pdf http://www.uaex.edu/Other_Areas/publications/PDF/FSA-6098.pdf

Pest Management

Weed control
http://www.ag.ndsu.nodak.edu/aginfo/pesticid/publications/GreenH/gpm-9.htm#Section11 (ND)
http://aesop.rutgers.edu/~Floriculture/publications/dirweed1.htm (NJ)
http://www.ces.ncsu.edu/depts/hort/hil/hil-570.html (NC)
http://www.umass.edu/umext/programs/agro/floriculture/floral_facts/ghweeds.htm (MS)

Disease control
http://www.ca.uky.edu/agcollege/plantpathology/PPAExten/PPFShtml/ppfsgh1.htm (KY)

Insect control (including biocontrol)
http://www.extension.umn.edu/distribution/horticulture/DG6682.html (MN)
http://ipmwww.ncsu.edu/biocontrol/2a.htm (NC)
http://www.ces.ncsu.edu/depts/ent/notes/Vegetables/veg17.html (NC)

Crop Specific Information

Tomato
http://ohioline.ag.ohio-state.edu/b672/b672_34.html (OH)
http://www.oznet.ksu.edu/library/HORT2/MF2074.PDF (KS)
http://www.ces.ncsu.edu/depts/hort/greenhouse_veg/gtp_outline.html (NC)
http://res2.agr.ca/harrow/bk/tom-toc.htm (Ontario)
http://msucares.com/pubs/p2257.html (MS)
http://msucares.com/pubs/pub1828.htm (MS)
http://ag.arizona.edu/hydroponictomatoes/index.htm (AZ)

Cucumber
http://www.oznet.ksu.edu/library/HORT2/MF2075.PDF (KS)
http://res2.agr.ca/harrow/bk2/cuke-toc.htm (Ontario)

Lettuce
http://www.cals.cornell.edu/dept/flori/lettuce/index.html (NY)

Organic Greenhouse Production
www.attra.org/attra-pub/ghveg.html (AR)
http://www4.ncsu.edu:8030/~jfmiles/ (NC)

Other Information

Organizations, conferences and suppliers
http://www.cals.cornell.edu/dept/flori/facts1.html

List of resources
www.attra.org/attra-pub/ghwebRL.html

List of references
http://www.ces.ncsu.edu/depts/hort/hil/hil-32-a.html

Greenhouse software programs
http://res2.agr.ca/harrow/software/software.htm

Decision support system for integrated crop management of greenhouse vegetables
http://res2.agr.ca/harrow/hgcm/hgcm.htm

(Lamb, - Vegetarian 01-06)

Sweet Onion Variety Trial, Spring 2001

Sweet (short-day) onions are a relatively minor crop in Florida. Production exists as both dry bulbs (mature) and green tops (immature). Limited production has existed throughout the state. The biggest deterrent for increased production is from competition from established markets in south Texas and middle Georgia areas. However, the potential exists for expanding production, especially in the areas of local sales and direct marketing.

The objective of this trial was to evaluate the performance of sweet onion varieties under north Florida conditions.

The transplants for this trial were produced from field beds at the NFREC, Quincy. Nineteen entries were seeded on 3 Oct 2000. Seed were planted at rate of about 30 seed per ft into rows spaced 12 inches apart. Preplant fertilization of seedbeds was 30-40-40lbs/a of N-P₂O₅-K₂O. Goal 2XL was applied over the top at 1 pt/a after seedlings reached the 2 true leaf stage. Seedbeds were top dressed once with 34 lbs N/a. Entries were transplanted into the production field on 11 Jan 2001. Soil type was an Orangeburg loamy fine sand. Preplant fertilization was 60-80-80 lbs/a of N-P₂O₅-K₂O. Production scheme was 3 rows spaced 15 inches apart under a 5 ft tractor and in-row spacing was 4 inches (78,404 plants/a). Goal 2XL at 2 pts/a was applied on soil surface before transplanting and Dacthal 75 W at 9 lbs ai/a was applied over the top after transplanting. Nitrogen was applied twice during the season at 50 lbs N/a each time. One top dressing of K₂O as KCl at 60 lbs/a was made during the season. Registered pesticides were applied as needed to control pests.

Entries were harvested as they matured, where mature is defined as when about 25% of the tops of an entry had fallen down naturally. Bulbs were lifted, allowed to dry for a few hours and tops and roots removed. Bulbs were then placed in bushel baskets and dried for 72 hours at 100^o F in large drying rooms. After drying time was complete, onions were removed, allowed to cool down and graded. Grading consisted of discarding culls (small onions, splits, off color and decayed) and sizing into medium (1.5-2 inches), large (2-3 inches) and jumbo (>3 inches) categories. Bulbs were then weighed and counted.

Harvest occurred from the period of 7 May to 21 May. Total yields ranged from 949 50 lb bags/a for ‘SSC 6436’ to 284 50 lb bags/a for ‘Nikita’ (Table 1). Four other entries produced yields as high as ‘SSC 6436’. Yields were good to excellent in 2001 except for the late entries due to several rain storms near harvest time that caused a high incidence of bulb rotting. ‘Linda Vista’ produced the largest bulb at 12.0 oz and ‘King Midas’ produced the smallest at 6.7 oz. Percent marketable bulbs ranged from a low of 50.1% for ‘Pegasus’ to a high of 99.0% for ‘King Midas.' Percent bolting level was very low (<1%) on all entries.

Table 1. Yield, percent marketable, average bulb weight and days to harvest of short-day onion trial, Spring 2001. NFREC, Quincy.
		Marketable Yield (50 lb sacks/A)
Entry	Source	Large	Jumbo	Total	Marketable (%)	Bulb Wt (oz)	Days to Harvest from Transplant
SSC 6436	Shamrock	73 b-dz	861 a	949 a	97.5 ab	10.2 b-d	116
Linda Vista	Petoseed	65 c-e	813 ab	890 ab	85.5 cd	12.0 ab	127
SSC 6371	Shamrock	61 de	794 ab	862 a-c	95.7 a-c	9.8 c-e	116
SSC 6372	Shamrock	95 ab	728 a-c	838 a-c	99.0 a	8.9 de	119
Nirvana	Sunseeds	61 de	764 ab	832 a-c	87.2 b-d	12.3 a	124
Chula Vista	Petoseed	90 bc	655 b-d	759 b-d	91.4 a-d	10.1 cd	124
Granex 7092	Petoseed	62 de	676 b-d	745 b-d	88.1 a-d	9.4 c-e	127
Sweet Melissa	Sunseeds	62 de	664 b-d	739 b-d	81.4 de	10.8 a-d	125
Georgia Pride	Shamrock	94 ab	586 cd	699 c-e	95.8 a-c	8.0 ef	116
Rio Bravo	Sunseeds	58 de	569 cd	634 d-f	88.8 a-d	9.9 c-e	124
Sweet Success	Sunseeds	45 e	576 cd	626 d-f	85.6 cd	11.0 a-c	125
Cyclops	Asgrow	95 ab	511 d-f	623 d-f	72.0 ef	9.6 c-e	130
Sweet Melody	Sunseeds	78 b-d	524 de	611 d-f	84.7 cd	9.1 c-e	124
EX 19013	Asgrow	43 e	502 d-f	552 e-g	60.5 g	10.4 b-d	130
King Midas	Sunseeds	118 a	353 e-g	495 f-h	99.0 a	6.7 f	119
Granex 33	Asgrow	65 c-e	339 fg	415 g-i	55.8 g	9.3 c-e	130
Pegasus	Asgrow	37 e	359 e-g	401 g-i	50.1 g	9.7 c-e	130
Yellow Granex Imp.	Sunseeds	44 e	326 g	376 hi	70.7 f	9.2 c-e	125
Nikita	Sunseeds	40 e	233 g	284 i	59.5 g	10.0 cd	130
z Mean separation by Duncan's Multiple Range Test, 5% level. Values in columns followed by the same letter are not significantly different.

(Olson - Vegetarian 01-06)

Vegetable Section Program - FSHS Annual Meeting

The Florida State Horticultural Society is holding its annual meeting June 11-12, 2001 at the Hutchinson Island Marriott Beach Resort and Marina, Stuart, Florida.

The following is for the Vegetable Section Program. For the complete program and other details, visit their website at: http://valencia.lal.ufl.edu/jkbu/fshs/index.html

June 11, 2001 Monday a.m.	Elliott Amphitheater
10:00	The southwest Florida pest and disease hotline - An Extension Success Story. E. McAvoy, Hendry County Cooperative Extension Service, UF.
10:15	The potential for use of biologically-based disease management products in Florida vegetable production. E.M. Lamb, Indiana River Research and Education Center, UF, and EN Rosskopf, USDA-ARS, Ft. Pierce.
10:30	Effect of metam sodium and methyl bromide on root-knot nematode, yellow nutsedge and damp-off on cucumber cv. Dasher II. R.T. McMillan, Jr. and H.H. Bryan, Tropical Research and Education Center, UF.
10:45	Distance between yellow nutsedge (Cyperus esculentus) and polyethylene-mulched bell pepper (Capsicum annuum) at which interference is minimal and maximal. T.N. Motis, S. J. Locascio, Horticultural Sciences Department, and J.P. Gilreath, Gulf Coast Research and Education Center, UF.
11:00	Competition of smooth amaranth (Amaranthus hybridus) and livid amaranth (A. lividus) with cucumber. A.D. Berry, W.M. Stall, B. Rathinasabapathi, Horticulture Sciences Department, G.E. MacDonald, Agronomy Department, and R. Charudattan, Plant Pathology Department, UF.
11:15	Influence of the biostimulant folcysteine on the interference of purple nutsedge (Cyperus rotundus L.) With eggplant (Solanum melongena L.) J. P. Morales-Payan and W. M. Stall, Horticultural Sciences Department, UF.
11:30	Progress toward developing new insecticides and miticides for spider mites in strawberry. J. F. Price, Gulf Coast Research and Education Center, UF.
11:45	An economic assessment of pre-harvest fungicide applications to control Botrytis Fruit Rot in annual strawberries. J. J. Haydu, Mid-Florida Research and Education Center and D. E. Legard, Gulf Coast Research and Education Center, UF.
Lunch Break
1:15	Sectional Business Meeting
1:30	The rise and fall of the Florida celery industry from 1895 to 1995. G.M. Talbott, Florida Celery Exchange, Winter Park, FL.
1:45	A decade of change in Florida’s greenhouse vegetable industry: 1991-2001. R. V. Tyson, Seminole County Cooperative Extension Service; B.C. Hochmuth, North Florida Research and Education Center, Suwannee Valley; G. J. Hochmuth, North Florida Research and Education Center, Quincy, and M.S. Sweat, Baker County Cooperative Extension Service, UF.
2:00	Competitiveness of the Spanish and Dutch greenhouse industries with the Florida fresh vegetable industry. D. J. Cantliffe and J. H. Vansickle, Horticultural Sciences Department, UF.
2:15	Hydroponically produced "Gallia" muskmelon - What’s the secret? N.L. Shaw, D. J. Cantliffe, and S. Taylor, Horticultural Sciences Department, UF.
2:30	Improving lettuce transplant quality in response to nitrogen nutrition in a floatation production system. P. Soundy and D. J. Cantliffe, Horticultural Sciences Department, UF.
2:45	Performance of greenhouse tomato varieties grown in soilless culture in north central Florida. J. C. Rodriguez, D. J. Cantliffe and N. Shaw, Horticultural Sciences Department, UF.
3:00-3:30	Discussion and Intermission
3:45	Muskmelon fruit yield response to K source and method of application. G. J. Hochmuth, North Florida Research and Education Center, and M. Gal, Horticultural Sciences Department, UF.
4:00	Interactions between nitrogen rates and cultivar on the yield of strawberry. E. J. Simonne, Horticultural Sciences Department, J. R. Duval and E. Golden, Gulf Coast Research and Education Center, UF.
4:15	Sulfur fertilization for polyethylene-mulched cabbage. A. D. Susila and S. J. Locascio, Horticultural Sciences Department, UF.
4:30	A comparison of resistance to gas diffusion through the seedcoat and hilum of triploid and diploid watermelon (Citrullus lanatus Matsum & Nakai). J. R. Duval, Gulf Coast Research and Education Center, UF; D. S. NeSmith and M. Rieger, Department of Horticulture, University of Georgia, Athens, GA.
4:45	Response of "Florida 47" tomato to seed and foliar applications of ‘silk’ biostimulant. A. A. Csizinsky, Gulf Coast Research and Education Center, UF.
June 12, 2001 Tuesday a.m.	Elliott Amphitheater
8:30	Results of sweet corn variety demonstrations on organic soils. K. D. Shuler, Palm Beach County Cooperative Extension Service, UF.
8:45	Cost comparisons of Boniato in Miami-Dade County, FL: 1980 vs. 2000. F. Roka, Southwest Florida Research and Education Center, M. Lamberts, Miami-Dade County Cooperative Extension Service; S. K. O’Hair, Tropical Research and Education Center, and R. Regalado, Miami-Dade County Cooperative Extension Service, UF.
9:00	Greenhouse production of several fresh-cut herbs in vertical hydroponic systems in north Florida. S.C. Stapleton and R. C. Hochmuth, North Florida Research and Education Center, UF.
9:15	Calabaza yield and size at two spacings when grown as a second crop on various plastic mulches. J. M. White, Mid-Florida Research and Education Center, UF.
9:30	Abundance and distribution of thrips Palmi karny on potatoes and eggplants. D. R. Seal, Tropical Research and Education Center, UF.

(White - Vegetarian 01-06)

Postharvest Handling Considerations for Greenhouse-Grown Beit Alpha Cucumbers

There is potential to produce the new Beit Alpha-type cucumbers under protected culture in Florida. These miniature cucumbers were developed in Israel and are similar to the Dutch greenhouse types, in that they have a thin skin and are seedless, but are significantly smaller, with ideal size ranging from about 5 to 7 inches (12.5 to 17.5 cm) in length and 3/4 to 1 1/4 inches ( 22 to 29 mm) in diameter. Tests conducted at the Florida-Israeli Protected Agriculture Project in Gainesville and at the North Florida Research & Education Center-Suwannee Valley in Live Oak have shown that these cucumbers yield well under a wide range of ambient temperatures found in greenhouses (Shaw, et al, 2001).

In order to successfully introduce a new specialty crop like Beit Alphas, consideration must be given to developing market demand and understanding postharvest handling parameters. Important aspects of developing market demand include consumer preferences (e.g., color, size, flavor) and buyer preferences (e.g., package size and weight). Key postharvest information is lacking that would allow commercial growers to successfully ship Beit Alphas to desired markets. Desirable quality parameters include firm texture, shiny, dark-green skin color, and freedom from shrivel, and mechanical injuries (abrasions, cuts, bruises). Therefore, shippers must know optimal storage conditions and cooling method, mechanical properties (resistance to compression, vibration), packaging types and threshold susceptibility to ethylene exposure. Other postharvest treatments, such as coatings, hot water immersion, and controlled/modified atmosphere storage, may also significantly extend product quality.

Recent observations of Beit Alphas at retail level showed preventable quality losses, indicating the need for information on proper handling of this new crop. Slicing-type cucumbers can be safely stored at 50 to 55^oF (10 to 13^oC) for 10 to 14 days, depending on cultivar (Hardenburg, et al., 1986). To minimize moisture loss and shrivel field-grown slicing cucumbers are usually coated with wax, while Dutch greenhouse-grown types are shrink-wrapped with plastic film.

This spring we performed preliminary postharvest tests with Beit Alpha cucumbers from both research sites and a commercial greenhouse operation. Panelists in our sensory evaluations commented that the flavor was excellent. At harvest, small-diameter fruits (3/4 inch; 22 mm) were consistently firmer (from 1 to 2 Newtons) and had a noticeably crisper texture than larger-diameter fruits (1 1/4 inch; 29 mm). This indicates that smaller cucumbers may be less susceptible to mechanical injuries during handling and shipping. ‘Sarig’ cucumbers stored at 50^oF (10^oC) and 95% relative humidity maintained high quality for more than 14 days (Fig. 2). After 5 days storage, uncovered cucumbers lost about 50% more fresh weight than those loosely covered with plastic film. Both ‘Sarig’ and ‘Alexander’ cultivars developed chilling-injury symptoms after 7 days storage at 45.5^oF (7.5^oC) or 41^oF (5^oC). Other tests are currently underway to determine the effectiveness of waxes and shipping containers including hinged, rigid containers (clamshells).

Crops grown under protected culture can become inoculated by decay pathogens. Sources of inoculum include nearby cull piles - diseased plants and fruits should never be discarded near the greenhouse (Fig. 3). In these tests, sclerotinia rot (Sclerotinia sclerotiorum) appeared on sound, ‘Sarig’ cucumbers following 7 days storage at 50^oF (10^oC) (Fig. 4). Although considered a minor problem in field production of cucurbits, the growth of this aggressive rot during cold storage shows the need for preventative control measures in the greenhouse.

Cross-contamination of fresh produce by human pathogens is also a serious threat to consumers, with reliable estimates in the U.S.A. indicating that a small, but increasing percent of foodborne illness is attributable to consumption of fresh produce. Production of vegetables in greenhouse structures holds potential for reducing the risk of foodborne illness by isolating the plants from potential environmental contamination. Employees should be instructed in proper hand washing and other sanitary techniques to avoid cross-contamination during harvest and handling.

For Further Information:

Hardenburg, R.E., A.E. Watada and C.Y. Wang. 1986. The commercial storage of fruits, vegetables, and florist and nursery stocks. U.S. Dept. Agric. Handbook 66. Washington DC.

Shaw, N.L., D.J. Cantliffe, J.C. Rodriguez, S. Taylor and D.M Spencer. 2001. Beit alpha cucumber - an exciting new greenhouse crop. Proc. Fla. State Hort. Soc. 113:247-253.

Authors:

Steven A. Sargent, Suzanne C. Stapleton, Multi-county extension agent-marketing, NFREC-Suwannee Valley and Abbie J. Fox, Senior Biological Scientist, Horticultural Sciences Dept.

Fig. 1. Beit Alpha cucumbers are harvested at small diameters, 3/4 to 1 1/4 inch (22 to 29 mm).	Fig. 2. ‘Serig’ cultivar maintained excellent quality after 14 days at 50° F (10° C) and 95% relative humidity.
Fig. 3. Sclerotinia rot on the plant.	Fig. 4. Sclerotinia rot developed after 7 days storage at 50° F (10° C).