Tomatoes on the Vine
Tomatoes originated in South America--specifically in Peru, Bolivia, and Ecuador. Columbus and other explorers brought tomatoes to Europe by the late 1400s. In Europe and the United States, tomatoes were used only as ornamental plants until the early 1800s because the fruit was thought to be poisonous. Tomatoes are a member of the botanical family Solanaceae, which contains many potentially poisonous plants (nightshade, nicotianas [includes tobacco and petunias], Jimson weed [belladonna], and mandrake), as well as edible plants (potatoes, capsicums, and eggplants). All members of this family have toxic alkaloids present in either their leaves or their fruits. Commercial tomato production did not begin until after 1860 when tomatoes were finally accepted by consumers. Since 1890, tomato breeding has developed varieties adopted for use around the world.
Tomatoes come in many different types of fruit--fresh or beefsteak types, grape, saladette, cherry, plum or paste, and others. Producing a mixture of these types may expand your marketing capabilities and prospects. Another recent introduction that may have a market niche is ornamental hanging basket tomatoes for the home garden market. You should determine your customers' desires and market needs before ordering seeds or plants. Producing a variety of types will enable you to offer your customer all of their tomato preferences.
There are two types of tomato plant growth habits: determinate and indeterminate. Determinate tomato plants will grow to a genetically specified height and produce all of their fruiting flowers at one time. Indeterminate tomato plants continue to grow and produce fruiting flowers throughout the entire season.
Heirloom tomato varieties have become popular in many local fresh markets. They are old varieties that have been passed down from generation to generation. They are generally not well suited to large-scale production for various reasons, including difficulty in shipping, lack of fruit firmness, uneven ripening, disease susceptibility, and indeterminate growth habit.
In the United States, tomatoes are harvested for two basic purposes: processing and fresh marketing. In recent years the United States has produced around 300,000 acres of processed tomatoes valued at $600 to $700 million and 130,000 acres of fresh-market tomatoes worth $1.4 to $1.6 billion (USDA Statistical Services bases value of production on total acres harvested times average price). Pennsylvania produces about 4,000 acres of fresh-market tomatoes with an annual value of between $15 and $25 million.
Processing tomato production has historically been an important part of the tomato industry in Pennsylvania, but it has declined in significance in the past decade.
Depending on location, fresh-market tomatoes are produced in Pennsylvania from the first of June (in a high tunnel) to the end of October. Fresh-market tomatoes are usually sold loose in bulk containers. Tomato cultivars recommended for Pennsylvania are listed below. All cultivars are listed in order of maturity (early to late.)
Recommended tomato cultivars for Pennsylvania
|Traditional Round Red Fruit||Sun Start||V, FR, S|
|Sunrise*||V, FR, S|
|Fabulous*||V, FR, TMV, S, A|
|Mountain Spring*||V, R|
|Solar Set*||V, R|
|Crista*||V, FR, RN, TSWV|
|Mountain Supreme*||EBR, V, FR|
|Mountain Fresh*||V, FR|
|Mountain Delight*||V, FR|
|Specialty Cherry||Sweet Million*||FR|
|Sweet 100||V, FR|
|Larger cherry type||Sweet Chelsea*||TMV, F, FR, N|
|Yellow Type||Gold Nugget (cherry tomato)|
|Mountain Gold*||V, FR|
A = alternaria stem canker resistant
EBR = early late blight
FR = fusarium resistant
N = root rot nematode resistant
RN = root knot nematode resistant
S = stemphylium wilt resistant
TMV = tobacco mosaic virus resistant
TSWV = tomato spotted wilt virus resistant
V = verticillium wilt resistant
NOTE * Denotes Hybrid variety
Six basic marketing alternatives are available to the tomato grower:
- wholesale markets
- local retailers (grocery stores)
- roadside stands
- pick-your-own operations
- processing firms
Options are available for growing processing tomatoes; however, this publication will focus on fresh-market tomatoes.
In wholesale marketing, either you or a shipper can take your crop to the market. Shippers generally sell and transport tomatoes for a predetermined price. Wholesale marketing is subject to the most price fluctuations. Marketing cooperatives generally use a daily pooled cost and price, which spread price fluctuations over all participating producers. Local retailers are another possible market, but you must take the time to contact produce managers and provide high-quality tomatoes when stores require them.
Roadside stands (either your own or another grower's) and pick-your-own operations provide opportunities to receive prices higher than wholesale for your tomatoes, but you may have some additional expenses for advertising, building and maintaining a facility, and providing service to your customers. With pick-your-own operations, you save on harvest costs, but you must also be willing to accept some waste and assume the risks of having the public come to your farm. For more information on marketing, consult Agricultural Alternatives: Fruit and Vegetable Marketing for Small-scale and Part-time Growers, Agricultural Alternatives: Developing a Roadside Farm Market, and Agricultural Alternatives: Cooperatives.
Tomatoes grow best on well-drained soils that have good air and water infiltration rates. You should conduct a soil test prior to planting tomatoes. Lime should be applied to achieve a pH of 5.8 to 6.6 according to soil test recommendations. You can obtain soil test kits at your local extension office.
Tomatoes require a constant supply of moisture during the growing season. However, excess water at any time during growth, especially after fruit set, may increase the fruit's susceptibility to cracking (both radial and concentric), which can reduce fruit quality and yield. For more information on crop irrigation, consult Agricultural Alternatives: Irrigation for Fruit and Vegetable Production and Agricultural Alternatives: Drip Irrigation for Vegetable Production.
Tomatoes are sensitive to cool night temperatures (below 55°F). The best temperature range for the growing season is between 60° and 90°F; temperatures above 90°F or below 55°F will slow the growth, pollination, and maturation of the crop.
Planting and Fertilization
Commercially produced tomatoes generally are started as transplants in the greenhouse 42 to 56 days prior to planting in the field. Because tomatoes are a warm-season crop, they should not be transplanted until soil temperatures 3 inches beneath the soil surface reach 60°F. Tomatoes should be grown on raised beds covered with red or black plastic mulch. Growing the plants with drip irrigation ensures optimum plant growth and yields and allows for easy fertilizer application during the growing season.
Growers generally plant 2,600 to 5,800 plants per acre in single rows with 18 to 30 inches between plants in the row on 5.0- to 6.5-foot centers. A double row of compact tomato varieties also can be planted on each plastic-covered bed (10,000 plants per acre). Fertilizer rates should be based on annual soil test results. Soil testing is vital for a high-quality crop of tomatoes, as many of the causes of poor fruit development and quality are nonbiological and due to poor nutrition. Start the season with an application of fertilizer based on the soil test results. Apply 50 percent of the fertilizer at soil preparation.
The best way to determine your in-season fertilizer needs is by using a tissue test. Plant tissue testing should be conducted at the start of flowering and again 2 to 3 weeks later when green fruit are on the vine. Tissue sample kits may be obtained at your local extension office as well as from independent labs.
Common nutritional needs at these critical points are additional calcium, magnesium, and potassium, as well as continuing applications of nitrogen and phosphorus. Nutrients are best applied through a fertilizer injection system connected to the drip irrigation system. According to Knott's Handbook for Vegetable Growers, tomatoes will require 80 to 90 pounds of N, 100 pounds of P2O5, and between 100 and 200 pounds of K2O during the growing season.
In order to produce high-quality tomatoes, the plants require support off the ground. Many growers use a production system known as the Florida String Weave System. First, wooden stakes 4 to 4.5 feet long and 1 inch square are driven into the ground to a depth of 12 inches. A consistent stake height should be maintained to aid in spray applications without constant adjustment of the boom sprayer. Stakes should be driven between every two plants and twine woven through the stakes to support the tomato stems. Second, twine should be secured to the end stake and strung along one side of the plants by weaving the twine around each stake. Repeat this procedure on the other side. The first level of twine should be at 8 to 10 inches above the ground and the last two levels should be approximately 6 to 8 inches apart. Normally, only three levels of twine are needed. Waiting until wet plants have dried before stringing tomatoes will help reduce the potential for spreading fungal diseases.
Weed control can be achieved with herbicides, plastic mulch, and a good crop-rotation system. Several preplant and postemergence herbicides are available for tomatoes, depending on the specific weed problem and tomato growth stage. If infestation levels are mild, early cultivation can help minimize weed problems.
Insects, especially Colorado potato beetles, can be a major problem in tomato production. Initial spring beetle populations generally will not feed on the tomato plants but will mate and lay thousands of eggs per acre. Early control of adult Colorado potato beetles can prevent crop losses. Aphids, corn ear worm, European corn borer, armyworm, thrips, whiteflies, spider mites, and fruit flies also can cause crop losses. Monitoring insect populations with traps or by weekly scouting will help you determine if you should use insecticides and how often you should spray.
Several tomato diseases can cause crop losses, including bacterial canker, bacterial speck, bacterial spot, leaf blights, viruses, early blight, late blight, anthracnose, and bacterial soft rot. Several fruit disorders are also caused by extremes in soil moisture or weather conditions. These include cat-facing, blotchy ripening, graywall, yellow shoulders, sunburn, sunscald, and fruit cracking. Plant diseases and fruit disorders can be managed by using fungicides and disease-resistant varieties, maintaining proper plant nutrition, rotating crops, and growing in soil with good air and water drainage.
Tomatoes can also be grown organically, but this will require a high level of management and monitoring to be economically successful. For more information about organic vegetable production consult Agricultural Alternatives: Organic Vegetable Production.
Harvest and Storage
Harvesting fresh-market tomatoes is labor intensive and requires multiple pickings. Tomatoes generally are harvested four to six times during the growing season, depending on plant type, maturity, and market value. Tomatoes for the wholesale market are usually picked at the mature green to breaker stage to prevent the fruit from becoming overripe during shipping and handling. Tomatoes may be left on the vine to ripen if you can bring ripe tomatoes to market quickly and in good condition. Markets such as farmers' markets, roadside stands, or other direct markets will allow you to vine-ripen the tomatoes before harvesting. After harvest, growers should check tomatoes for size, color, and defects to ensure marketing a high-quality product.
Tomato storage is determined by maturity. Mature green tomatoes ripen at an optimum temperature range of 63 to 70°F and will not ripen normally if temperatures are higher than 80°F or lower than 55°F. Mature red tomatoes will retain high quality for approximately four to seven days if stored at 90 to 95 percent humidity and 46 to 50°F.
All agricultural producers in Pennsylvania, including small-scale and part-time farms, operate under Pennsylvania's Clean Streams Law. A specific part of this law is the Nutrient Management Act. Portions of the Nutrient Management Act (Act 38) may pertain to you, depending on the mix of enterprises you have on your farm (in particular, animal operations). Because all farms are a potential source of surface- or groundwater pollution, you should contact your local Soil and Water Conservation District to determine which regulations may pertain to your operation.
There are several risk-management strategies you may want to employ for your farm. You should insure your buildings and equipment, and you may also want to insure your crops. Insuring your farm may be accomplished by consulting your insurance agent or broker. You can also insure individual crops (like tomatoes) through traditional crop insurance policies and your whole-farm income through a program called AGR-Lite. To obtain AGR-Lite insurance you will need your last five years of Internal Revenue Service (IRS) Schedule F forms. Both types of policies are federally subsidized and are available from private crop insurance agents. Contact a crop insurance agent to see which type of coverage makes the best sense for you.
For more information on agricultural business insurance, please see Agricultural Alternatives: Agricultural Business Insurance. More information on crop insurance can be found on the Penn State Extension website.
Included in this publication is a sample fresh-market tomato production budget. This budget utilizes custom hire for some of the field work. Hiring custom operators and labor may be a more viable option for small-scale or beginning producers, considering the large capital expenditures required for equipment. You should also investigate renting specific pieces of equipment like plastic mulch layers. Producers who own equipment should substitute equipment costs for custom-hire costs. This budget summarizes the receipts, costs, and net returns of a tomato enterprise and should help ensure that all costs and receipts are included in your calculations. Costs and returns are often difficult to estimate in budget preparation because they are numerous and variable. Therefore, you should think of this budget as an approximation and make appropriate adjustments in the "Your Estimate" column to reflect your specific production and resource situation. More information on the use of crop budgets can be found in Agricultural Alternatives: Enterprise Budget Analysis.
You can make changes to the interactive PDF budget files for this publication by inputting your own prices and quantities in the green outlined cells for any item. The cells outlined in red automatically calculate your revised totals based on the changes you made to the cells outlined in green. You will need to click on and add your own estimated price and quantity information to all of the green outlined cells to complete your customized budget. When you are done, you can print the budget using the green Print Form button at the bottom of the form. You can use the red Clear Form button to clear all the information from your budget when you are finished.
Sample Budget Worksheet
Initial Resource Requirements
Land: 1 acre
Labor: 19 hours per acre
Harvesting: $800 per acre
Capital: $6,000 per acre
Depreciation on equipment: $600 per acre
- Tractor--40 to 60 hp
- Tillage equipment
- Transplanter--may be rented
- Sprayer--boom type
- Wagon or trailer
For More Information
Dunn, J. W., J. W. Berry, L. F. Kime, R. M. Harsh, and J. K. Harper. Agricultural Alternatives: Developing a Roadside Farm Market. University Park: The Pennsylvania State University, 2006.
Dunn, J. W., J. K. Harper, and G. L. Greaser. Agricultural Alternatives: Fruit and Vegetable Marketing for Small-scale and Part-time Growers. University Park: The Pennsylvania State University, 2000.
Dunn, J. W., J. K. Harper, and L. F. Kime. Agricultural Alternatives: Cooperatives. University Park: The Pennsylvania State University, 2005.
Greaser, G., and J. Harper. Agricultural Alternatives: Enterprise Budget Analysis. University Park: The Pennsylvania State University, 1994.
Hardenburg, R. E., A. E. Watada, and C. Y. Wang. Agricultural Handbook Number 66: The Commercial Storage of Fruits and Nursery Stocks. Washington, D.C.: USDA-ARS Superintendent of Documents, Government Printing Office, 1986.
Kime, L. F., J. A. Adamik, E. E. Gantz, and J. K. Harper. Agricultural Alternatives: Agricultural Business Insurance. University Park: The Pennsylvania State University, 2004.
Lamont, W. J., Jr., J. K. Harper, A. R. Jarrett, M. D. Orzolek, R. M. Crassweller, K. Demchak, and G. L. Greaser. Agricultural Alternatives: Irrigation for Fruit and Vegetable Production . University Park: The Pennsylvania State University, 2001.
Lamont, W. J., Jr., M. D. Orzolek, J. K. Harper, A. R. Jarrett, and G. L. Greaser. Agricultural Alternatives: Drip Irrigation for Vegetable Production. University Park: The Pennsylvania State University, 2002.
Maynard, D. M., and G. J. Hochmuth. Knott's Handbook for Vegetable Growers. 4th ed. New York: John Wiley & Sons, 1997.
MacNab, A. A., A. E. Sherf, and J. K. Springer. Identifying Diseases of Vegetables. University Park: The Pennsylvania State University, 1994.
Pennsylvania Commercial Vegetable Production Recommendations. University Park: The Pennsylvania State University, 2006.
Sanchez, E. S., M. D. Orzolek, J. K. Harper, and L. F. Kime. Agricultural Alternatives: Organic Vegetable Production. University Park: The Pennsylvania State University, 2003.
Seelig, R. A. Fruit & Vegetable Facts & Pointers: Tomatoes. Alexandria, Va.: United Fresh Fruit and Vegetable Association, 1969.
Pennsylvania Vegetable Growers Association
RR 1, Box 392
Northumberland, PA 17857-9723
Some Heirloom Tomato Seed Sources
Johnny's Selected Seeds
Foss Hill Road
Albion, ME 04910-9731
Rupp Seeds, Inc.
17919 County Road B
Wauseon, OH 43567
Tomato Growers Supply Co.
P.O. Box 60015
Fort Myers, FL 33906
Territorial Seed Co.
P.O. Box 158
Cottage Grove, OR 97424-0061
Seeds of Change
334 West Stroud Street
Randolph, WI 53956-1274
Prepared by Michael D. Orzolek, professor emeritus of horticulture; Steven M. Bogash, retired extension educator; R. Matthew Harsh, retired extension educator; Lynn F. Kime, senior extension associate in agricultural economics; and Jayson K. Harper, professor of agricultural economics.
This publication was developed by the Small-scale and Part-time Farming Project at Penn State with support from the U.S. Department of Agriculture-Extension Service.