Potato Production

Potato Production

Due to the wide diversity in types and high consumer consumption, potatoes are a good enterprise option for many farms. They can be marketed directly to consumers at farm stands, farmers' markets, and through other local retail outlets. There is also a substantial wholesale market in the Mid-Atlantic region based on increasing demand for locally produced foodstuffs and specialty-type potatoes. Wholesale marketers should consider local and regional produce auctions, grocer local-buyer programs, and direct-to-restaurant sales. The diversity of potatoes is just beginning to be realized as more and improved specialty potatoes with different skin or flesh colors and uses are being grown and marketed. The use of different colors adds to the visual appeal of potatoes on display and can attract attention at a retail outlet.

Potatoes (Solanum tuberosum) are the world’s most important vegetable crop. They originated in the Andean region of South America. They were cultivated by early Andean civilizations and brought to Europe by the Spaniards, where they were marketed as early as 1576. The potato was then introduced to the rest of Europe, where the Irish were the first to recognize it for its high food value. By the early 1600s potatoes became the staple food of the Irish, with the majority of the people depending on them for their existence. When late blight disease came to Ireland from America, it caused a national famine from 1845 to 1848 that resulted in the death of nearly one million people and the mass overseas migration of one million more. Late blight caused the death of the potato vines and decay of the tubers, resulting in a total loss of the crop. Late blight, although manageable, is still a challenge for growers today.

Potatoes were introduced into the United States in 1719 from stock brought from Ireland and were first grown in New Hampshire. Today, the United States harvests around 400-425 million hundredweight (cwt) of potatoes with an approximate value of $3.9-$4.2 billion annually from around 900,000 acres. The northeastern states combine for around 80,000 acres each year; Pennsylvania potatoes supply both the processing (primarily for potato chips) and fresh (or tablestock) markets.

Marketing

Potatoes grown for the fresh market are marketed in the Northeast from mid-July through late September if not stored and from mid-September until mid-May if held in storage. Fresh-market potatoes are sold loose, in containers, and in 3-pound to 50-pound paper or poly bags. "B" size potatoes, which were once discarded as too small or kept for seed, are now commonly marketed in 1.5-pound clamshells or in quart baskets as a ready-to-use product.

Three basic marketing alternatives are available to the potato grower: wholesale markets, retail markets, and processing:

1. In wholesale marketing, producers negotiate a price with retail chain stores. Cooperatives such as the Pennsylvania Co-Operative Potato Growers market potatoes to a wide variety of outlets. Produce auctions provide another excellent outlet for new and smaller growers since all product is generally sold, but the price will vary with demand, the quantity of other potatoes at the auction, quality, and type of potato.
2. Local retailers (individual grocery stores) are another possibility, but you must take the time to contact produce managers and provide high-quality potatoes when the stores require them. Roadside stands (either your own or another grower's) provide opportunities to receive higher-than-wholesale prices for your potatoes, but you may have some additional expenses for advertising, building and maintaining a facility, transportation, and providing service to your customers. CSAs (community-supported agriculture) may be another option. CSAs strive to provide a wide variety of products for as long as possible, so potatoes are a good match for other crops such as winter squash and root crops for fall and winter sales or markets. Some growers sell to local restaurants. Because chefs stay up on trends, this may be an important avenue to sell high-end specialty potatoes that may not be as recognized in other markets.
3. Pennsylvania is one of the top potato processing states in the country. This output is almost entirely in the form of potato chips. Although it is an important part of Pennsylvania's large food processing industry, most of the potatoes used come from out-of-state. The acreage of chipping potatoes grown in Pennsylvania is still significant but has been declining for many years. Potato cultivars used for chipping have been selected for their frying characteristics and are generally not good choices for general tablestock use. Most chipping potatoes are grown by larger farming operations on a contract basis. Processors are not likely to contract with small-acreage growers.

Production Considerations

Planting and Fertilization

Potatoes grow best in deep to moderately deep, loose, well-drained soils. The soil should have a pH of 5.5 to 6.5. The best method to determine lime and fertilizer requirements is annual soil testing. Some factors to consider in the fertility program are the method of fertilizer application, crop use (fresh or processing), cultivar, length of the growing season, and manure applications. The fertility value of a legume crop grown the previous season should also be considered. Excess nitrogen fertilization delays maturity, while excess potassium greatly hinders the uptake of magnesium and reduces the firmness of the potato (decreases the specific gravity). Magnesium is recommended when soil levels of magnesium are low, or potassium levels are excessively high.

Potato cultivars recommended for the northeastern U.S. are listed in Table 1. Use only certified seed or seed known to be free of virus diseases. Space seed pieces 7 to 12 inches apart in the row. Spacing varies with potato cultivar, soil type, amount of moisture available, fertility and the amount of fertilizer applied, and potato size desired at harvest time (closer planting yields smaller potatoes).

For conventionally grown potatoes, the amount of nitrogen applied typically ranges from 150 to 180 pounds per acre depending on the cultivar. Cultivation is often used to break the soil crust, promote aeration, and kill the first flush of weeds not controlled by herbicides. Later the potatoes have soil ridged over the rows ("hilled") to prevent greening and control weeds in the row. If hilling is delayed, be careful to minimize root damage caused by tillage. Hilling should be completed before the potato plants start to bloom. Potatoes are typically fertilized three times:

1. at planting when approximately one-third of the nitrogen and all of the phosphate and potash is broadcasted and disked in,
2. four to five weeks later another third of the nitrogen is side-dressed, and
3. remaining nitrogen is added based on petiole nitrate testing at flowering.

Early

Midseason

Late

For suitability for use as tablestock or chipping, relative yield, reported disease resistance, and spacing see the Mid-Atlantic Commercial Vegetable Production Recommendations guide or seed catalogs/websites.

Potatoes are well suited for production in a plasticulture system (using raised beds, plastic mulch, drip irrigation, fertigation, row covers, and even fumigation, if needed). Although primarily used by smaller growers (less than 5 acres of potatoes) due to the slower planting speed and specialized equipment required, this method produces excellent yields of high-quality potatoes. Plastic mulches warm up the soils faster in the spring and hasten the emergence of the potato plants. The plastic mulch also prevents weeds and eliminates the need to hill and cultivate. Because drip irrigation provides complete control over the amount of moisture applied, it is also an excellent method for applying precise amounts of nutrients. Tissue-culture sampling should be used to measure plant nutrient needs so excessive fertilizer is not applied. The only drawback to plasticulture is in handling the waste plastic at the end of the season. Due largely to eliminating preemergence herbicides, plasticulture greatly simplifies the production of organic potatoes.

Pest Management

Like nearly all vegetable crops, you will need to manage weeds, diseases, and insect pests when growing potatoes. By practicing integrated pest management (IPM), you can greatly reduce your reliance on pesticides. IPM includes the use of crop rotation, cover crops, good nutrient management, predictive computer models for insect pests and diseases, crop scouting, improved cultivars, and related practices and techniques to produce a high-quality crop and keep pesticide use to a minimum. In an IPM protocol, the primary crop management differences between a certified organic grower and other growers are in the selection of pesticides and nutrient management strategies. Organic growers can only use pesticides and nutrient sources permitted under the National Organic Standards, while conventional growers can use any federally approved pesticide or inorganic fertilizer.

Weed management can be achieved with herbicides, cultivation, plastic mulch, and crop rotation. Several preplant and post-emergence herbicides are available for potatoes depending on the specific weed problem and potato growth stage. A long-term crop-rotation scheme can greatly reduce populations of difficult-to-control weeds because it allows you to vary cultivation practices and rotate herbicides. Early cultivation can be used when weeds are young and before the potato canopy has closed.

Several insects can cause severe problems in potatoes, including Colorado potato beetles, flea beetles, aphids, leafhoppers, wireworms, and corn borers. Monitoring insect populations by scouting is critical in determining when you should use insecticides and which materials you should apply. Local and regional corn borer trapping programs focused on sweet corn can provide important local information on when to time spray applications. Wireworms are a particularly difficult pest that can be monitored using field corn monitoring stations.

Several potato diseases can cause severe crop losses if not properly managed. These include early blight, late blight, common and powdery scab, blackleg, leaf roll and mosaic viruses, rhizoctonia, verticillium wilt, fusarium dry rot, and bacterial soft rot. Although the list of diseases to manage is long, most diseases can be managed with disease-resistant cultivars, crop rotation, and the proper use and timing of fungicides. It is also important to be aware of weather conditions that are related to the spread of certain diseases such as late blight. Computer models based on local and regional weather patterns provide important data to help in managing diseases.

Harvest and Storage

Depending on the cultivar grown, potatoes are generally harvested from mid-July through October in the Northeast U.S. Potatoes are harvested when they are mature or when the skins are set. In any case, harvest when the air and soil temperatures are above 45°F. Care should be taken to prevent bruising potatoes during harvesting, storing, grading, and marketing. Newly harvested potatoes can be sold immediately after harvest. Consumers and restaurants often seek out these "fresh" or "new" potatoes, which often bring a premium price. Because the skins are very tender, handle them carefully, wash them only as much as necessary, allow them to dry, and get them to market quickly.

When storing potatoes, ventilation, storage temperatures, and relative humidity are important factors to consider. Storage conditions during the first 10 to 14 days are critical to healing cuts and bruises in newly harvested potatoes to ensure you have a high-quality crop to market. Make sure there is good air movement, a temperature of about 65°F, and high relative humidity (85 to 90 percent) in the potato storage facility during this period. The temperature should then be reduced very slowly (one degree per day) to the final storage temperature. Potatoes stored longer than three months for the fresh or tablestock market should be held at 38–40°F. Maintain relative humidity at 85 percent or higher to help prevent shrinkage and pressure bruising and to keep the potatoes firm. Consult with an agricultural engineer who is familiar with the construction of potato storage when building a new potato storage facility or renovating an older facility. Plastic bulk containers are recommended for storing larger quantities of potatoes because they are much easier to clean than wooden ones.

Environmental Impacts

In the normal course of operations, growers handle pesticides and other chemicals, may have manure to collect and spread, and use equipment to prepare fields and harvest crops. Any of these routine on-farm activities can be a potential source of surface or groundwater pollution. Because of this possibility, understand the regulations you must follow concerning the proper handling and application of chemicals and the disposal and transport of waste. Depending on the watershed where your farm is located, there may be additional environmental regulations regarding erosion control, pesticide leaching, and nutrient runoff. Contact your soil and water conservation district, extension office, zoning board, state departments of agriculture and environmental protection, and your local governing authorities to determine what regulations may pertain to your operation.

Good Agricultural Practices and Good Handling Practices

Good agricultural practices (GAP) and good handling practices (GHP) are voluntary programs that you may wish to consider for your operation. The idea behind these programs is to ensure a safer food system by reducing the chances for foodborne illnesses from contaminated products reaching consumers. Also, several major food distribution chains are beginning to require GAP- and GHP-certified products from their producers. These programs set standards for worker hygiene, use of manure, and water supply quality.

These handling practices require an inspection from a designated third party and there are fees associated with the inspection. Prior to an inspection, you will need to develop and implement a food safety plan and designate someone in your operation to oversee this plan. You will need to have any water supply used by your workers or for crop irrigation and pesticide application checked at least twice each year. A checklist of the questions to be asked during the inspection can be found online. For more information about GAP and GHP, contact your local extension office or your state’s department of agriculture.

Risk Management

You may wish to consider several risk-management strategies for your operation. First, you should insure your facilities and equipment. This may be accomplished by consulting your insurance agent or broker. Second, you may wish to insure your potato crop with crop insurance. Third, you may wish to insure the income of your entire farm through a crop insurance program called Whole-Farm Revenue Protection (WFRP).

Crop insurance is a federally subsidized program that is available from private crop insurance agents. Crop insurance for potatoes, available in 14 Pennsylvania counties, is based on your actual production history and you choose the level of protection that best protects your farming operation. The deadline to sign up for this insurance plan is March 15. Whole-Farm Revenue Protection (WFRP) is another crop insurance option that insures the revenue of your entire farm (including any livestock) by guaranteeing a percentage of your approved farm revenue. WFRP uses information from the past five consecutive years of your Schedule F tax records to calculate the policy’s approved revenue guarantee. The sign-up deadline for WFRP is March 15 for calendar year and early fiscal year tax filers and November 20 for late fiscal year tax filers.
Finally, the USDA Farm Service Agency has a program called the Non-Insured Disaster Assistance Program (NAP) that is designed to provide a minimal level of yield risk protection for producers of commercial agricultural products that don’t have multi-peril crop insurance coverage. NAP is designed to reduce financial losses when natural disasters cause a catastrophic reduction in production. NAP coverage is available through your local USDA Farm Service Agency office. The application fee for this program may be waived for eligible limited-resource farmers.

For more on agricultural business insurance, see Agricultural Alternatives: Agricultural Business Insurance. For more information concerning crop insurance, contact a crop insurance agent and the publication Crop Insurance for Pennsylvania Vegetable Crops.

Budgeting

The sample budgets included in this publication summarize the costs and returns for tablestock potatoes grown both conventionally and in a plasticulture system. Both budgets utilize custom hire for most of the field work, which could be more economical for small-acreage growers. If you have your own equipment, substitute your equipment costs for the custom hire costs. These sample budgets 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 these budgets 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: Budgeting for Agricultural Decision Making.

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 Potato Budgets

Sample Potato Budget - Conventional Production

Sample Potato Budget - Plasticulture Production

For More Information

Publications

Christ, B. J. Identifying Potato Diseases in Pennsylvania. University Park: The Pennsylvania State University, n.d.

Dunn, J. W., J. K. Harper, and L. F. Kime. Agricultural Alternatives: Fruit and Vegetable Marketing for Smallscale and Part-time Growers. Penn State Extension, 2009.

Harper, J. K., S. Cornelisse, L. F. Kime, and J. Hyde. Agricultural Alternatives: Budgeting for Agricultural Decision Making. EE0092. Penn State Extension, 2019.

Johnson, D. A, ed. Potato Health Management. St. Paul, Minn.: APS Press, 1993.

Kime, L. F., J. A. Adamik, J. K. Harper, and C. Dice. Agricultural Alternatives: Agricultural Business Insurance. UA406. Penn State Extension, 2019.

Lamont, W. J., 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. Penn State Extension, 2001.

Lamont, W. J., M. D. Orzolek, J. K. Harper, L. F. Kime, and A. R. Jarrett.  Agricultural Alternatives: Drip Irrigation for Vegetable Production. Penn State Extension, 2012.

Hochmuth, G.L. and R.G. Sideman. Knott's Handbook for Vegetable Growers. 6th ed. New York: John Wiley and Sons, 2022.

Stevenson, W., Rosemary Loria, Gary D. Franc, and D. P. Weingartner, eds. Compendium of Potato Diseases. 2nd ed. St. Paul, Minn.: APS Press, 2001.

Wyenandt, C.A., and M.M.I. van Vuuren, coordinators. 2020/2023 Mid-Atlantic Commercial Vegetable Production Recommendations. University Park: Rutgers NJAES Cooperative Extension, 2022.

Associations

Pennsylvania Cooperative Potato Growers, Inc.

3107 North Front Street
Harrisburg, PA 17110-1310
717-232-5200

Pennsylvania Vegetable Growers Association
815 Middle Road
Richfield, PA 17086-9626
717-473-8468

Websites

• Kimberly Research and Extension Center
• International Potato Center
• Maine Potato Board
• National Potato Council
• Nebraska Potato Eyes
• Northwest Potato Research
• Oregon State University Potato Research and Extension
• Potato Association of America
• Potato News
• University of Idaho
• University of Maine
• University of Nebraska-Lincoln's Potato Education Guide

Initial Resource Requirements: Conventional Production

• Land: 1 acre
• Labor: $500.00 to $600.00
• Capital: $2,500.00 to $3,800.00
• Equipment: Tractor (50 to 75 hp)
• Boom sprayer
• Potato harvester

Initial Resource Requirements: Plasticulture Production

• Land: 1 acre
• Labor: $800.00 to $1,000.00
• Capital: $3,500.00 to $4,700.00
• Equipment: Tractor (50 to 75 hp)
• Boom sprayer
• Plastic mulch layer
• Mulch lifter
• Irrigation system
• Rotary mower

Authors

Prepared by Elsa S. Sánchez, professor of horticultural systems management; Lynn F. Kime, senior extension associate; 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.