Asparagus Production

Asparagus Production

Asparagus is a perennial crop that lends itself well to smallscale and part-time farming operations. Multiple markets exist for growers with plantings of one acre or less, and many field operations that require machinery, such as land preparation and planting, can be custom hired.

Asparagus (Asparagus officinalis) is a member of the asparagus family (Asparagaceae) and one of only a few vegetables that are monocots (plants having only one cotyledon, or seed leaf). Asparagus plant are dioecious, meaning female and male flowers are produced on different plants. Plants use more energy to produce fruit on female plants; seed produced can result in new plants germinating, which can overcrowd beds. Newer all-male hybrids tend to have thicker stems and better yields.

Generally, spears are harvested when they are 7 or 9 inches in length and green in color. Purple-speared cultivars are also available on the market. Excluding light when spears are emerging will produce blanched, or white, spears.

Asparagus is believed to be indigenous to parts of Russia, the Mediterranean region, the British Isles, and parts of Africa. It was first cultivated by the early Romans, Greeks, and Egyptians, who used asparagus for food and medicinal purposes. It was cultivated in England over two thousand years ago and brought to North America by the early colonists. However, asparagus was not extensively planted by commercial growers until after 1850.

Most of the asparagus harvested in the United States is sold as fresh produce. The United States produces around 20,000 to 25,000 acres of asparagus with a value of $70 to $100 million annually. The largest asparagus-producing states are Michigan, California, New Jersey, and Washington. Asparagus is produced on 4,900 farms in the United States and 75 percent of those farms have one acre or less. U.S. acreage is currently less than one-third of what it was 20 years ago due to increased imports from Central and South America.

Marketing

Locally produced asparagus is available in the northeastern United States from late April through June. It is traditionally sold in pyramid crates packed with 1.5- to 2.5-pound bunches held with a rubber band. Several marketing alternatives are available, including wholesale marketing, produce auctions, cooperatives, local retailers, roadside stands, farmers markets, community-supported agriculture (CSA), and pick-your-own operations. When planning production, first consider your ability and access to market. You should conduct some market research—new growers often overestimate their ability to sell in a given market. Production of less than one acre of many vegetable crops is typical for most growers. Asparagus is an early season crop, which may benefit retail marketers when combined with other crops.

In wholesale marketing, producers often contract with shippers to market and ship their asparagus for a pre-determined mined price. If you do not use a contractor and ship your asparagus to a wholesale market yourself, your product will be subject to the greatest price fluctuations. Produce auctions operate weekly; however, you must deliver the asparagus to the auction. Marketing cooperatives generally use a daily pooled cost and price, which spreads price fluctuations over all participating producers. Local retailers are another possible market, but you must take the time to contact produce managers and provide good-quality asparagus when stores require it. Depending on your location, processors may or may not be a marketing option. Processors are less likely to contract with small-acreage growers (those with fewer than 5 acres). For more information on marketing, consult "Agricultural Alternatives: Fruit and Vegetable Marketing for Small- Scale and Part-Time Growers."

Retail marketing options include roadside stands (either your own or another grower's), farmers markets, and CSAs. These options can provide opportunities to receive higher- than-wholesale prices for your asparagus, but you may have some additional expenses for advertising, building and maintaining a facility, and providing service to your customers. Farmers markets are another retail option, but you should contact the markets well in advance of the marketing season to be sure space is available and to find out what requirements you must follow. For more information about roadside markets, see "Agricultural Alternatives: Developing a Roadside Farm Market."

Production Considerations

Asparagus should be grown on soils that are not compacted, have good drainage, and hold moisture well. Soil pH should be between 6.2 and 7.0. Avoid planting asparagus in fields where it has been grown in previous years. Asparagus is a self-allelopathic species—it produces and releases toxic chemicals that inhibit and suppress the growth of young asparagus transplants or crowns. In addition, asparagus is extremely susceptible to Fusarium root rot, a disease caused by a fungus that will weaken the plant. The Fusarium fungus can survive up to seven years in infected soil and soil fumigation is not effective in reducing long-term soil populations. Asparagus is also extremely salt tolerant.

Planting and Fertilization

Commercially, asparagus can be started in the greenhouse 8 to 10 weeks prior to transplanting in the field or planted as one- or two-year-old crowns. Crowns are developed root systems with a fairly defined storage organ and growth buds.

Growers generally plant approximately 12,000 to 14,000 plants per acre in single rows, with 12 inches between plants in the row and 5 to 6 feet between rows. Whether planting crowns or transplants, the asparagus is planted in an 8-inch deep furrow with a W-shaped configuration at the bottom of the furrow. The crown and transplant are planted in the W-shaped furrow beneath the soil surface, and the furrow is gradually filled with soil during the growing season. Asparagus usually is planted in May so that extensive foliage (fern) develops before winter.

Fertilizer recommendations should be based on annual soil test results. In the absence of soil test results, the recommended N-P-K application rates are 50-100-150 pounds per acre broadcast in the spring of every year before spear emergence.

Pest Control

Weed control can be achieved with light cultivation, straw mulch, and/or herbicides. Several preplant and postemergence herbicides are available for asparagus, depending on the specific weed problem and the time of year. If infestation levels are light, early cultivation (prior to spear emergence) can help reduce weed problems.

Insects can be a major problem in asparagus production. Asparagus beetles, asparagus aphids, cutworms, and Japanese beetles can all cause crop losses. A good integrated pest management plan will help you manage insect and other pests.

Several asparagus diseases can reduce crop yields, especially Fusarium root rot and rust. These diseases can be prevented by having good water and air drainage and planting disease-resistant cultivars.

Irrigation

Irrigation is highly recommended and will help ensure a more consistent crop from year to year. Trickle irrigation is preferred over overhead irrigation because it adds water directly to the root zone and does not wet the foliage. Also, very little water is lost from evaporation. More information on drip irrigation can be found in "Agricultural Alternatives: Drip Irrigation for Vegetable Production."

Harvest and Storage

The length of time for harvesting asparagus each year increases gradually until the plants reach full maturity (five years). The first year after planting, asparagus can be harvested for about seven days; the second-year harvest period lasts for about 14 days; the third-year harvest period is about three weeks; the fourth-year harvest period is 30 to 36 days; and by year five (when the plants have reached full maturity) the harvest period is approximately six to seven weeks. Asparagus spears can be cut with an asparagus knife or snapped off near the soil line. Spears are harvested when they reach at least 7 inches in height and have a spear diameter of at least 5/16 inch. When growing under seasonal temperatures, asparagus should be harvested every day since spears can increase in length by as much as 2 inches per day. Harvesting asparagus when it is greater than 12 inches in length (spear diameter becomes thinner) will reduce the total marketable harvest over the life of the planting.

Proper postharvest handling of asparagus is critical to marketing success. You should cool the picked asparagus immediately after harvest to remove field heat and improve shelf life. Refrigeration immediately after harvest will help guarantee high quality. Asparagus that is maintained at 32 to 36°F and 90 to 95 percent relative humidity will retain good quality for approximately seven to 14 days.

Environmental Impacts

All agricultural operations in Pennsylvania, including small-scale and part-time farming enterprises, operate under the Pennsylvania Clean Streams Law. A specific part of this law is the Nutrient Management Act. Portions of the act may or may not pertain to your operation, depending on whether you have livestock on your farm. However, all operations may be a source of surface water or groundwater pollution. Because of this possibility, you should contact your local Soil and Water Conservation District 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 resulting 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 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.

You may also be impacted by the regulation Food Safety and Modernization Act (FSMA) administered by the Food and Drug Administration (FDA). The Act governs record keeping, health and hygiene, water quality, and animal waste used as fertilizer among additional requirements. For more information covering FSMA, visit the Penn State Extension's FSMA webpage.

Risk Management

You should carefully consider how to manage risk on your farm. First, you should insure your facilities and equipment. This may be accomplished by consulting your insurance agent or broker. It is especially important to have adequate levels of property, vehicle, and liability insurance. You will also need workers compensation insurance if you have any employees. You may also want to consider your needs for life and health insurance and if you need coverage for business interruption or employee dishonesty. For more on agricultural business insurance, see "Agricultural Alternatives: Agricultural Business Insurance."

Second, check to see if there are multi-peril crop insurance programs available for your crop or livestock enterprises. There are crop insurance programs designed to help farmers manage both yield risk and revenue shortfalls. However, individual crop insurance coverage is not available for all crops. If individual coverage is not available for what you grow, you may be able to use the Whole Farm Revenue Protection (WFRP) program to insure the revenue of your entire farm operation. Information from your Schedule F tax records (or a "Substitute Schedule F for WFRP Purposes" if you do not file a Schedule F) from the past five consecutive years is used to calculate the WFRP policy's approved revenue guarantee. Operations that have expanded over time may be allowed to increase the approved revenue amount based on an indexing procedure. Depending on the number of commodities grown, you have the choice of coverage of 50 to 85 percent of your approved revenue. Coverage and premium costs depend on the level of diversification in your operation; the maximum level of insured revenue is $8.5 million (based on maximum adjusted gross revenues of $17 million and the 50 percent coverage level). WFRP also provides replant coverage if it not already covered under an underlying individual crop policy. More information on WFRP can be found at the RMA website.

Finally, the USDA Farm Service Agency has a program called the Noninsured 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 catastrophic reduction in production. A basic level of coverage (50 percent of expected production at 55 percent of the average market price) is available for a fee of $325 per crop per county (fees are capped at $825 per producer per county, but not to exceed a total of $1,950 for producers growing crops in multiple counties). Higher levels of protection at the 50, 55, 60, and 65 percent levels at 100 percent of the average market price are available for additional premium. 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.

Sample Budgets

Included in this publication are sample fresh-market asparagus budgets. All budgets utilize custom hire for most of the field work, which could be more economical for a smaller acreage. If you have your own equipment, substitute your costs for the custom-hire costs. The first budget summarizes the costs of establishing an asparagus enterprise (there is no income during the year of establishment). The other budgets summarize the receipts, costs, and net returns of an asparagus enterprise for the first year after planting, the second year after planting, and a mature crop. 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 approximations and make appropriate adjustments in the "Your Estimate" column to reflect your specific production and resource situation. These budgets are developed for one acre; however, your scale of production should be based on your market considerations. More information on the use of crop budgets can be found in "Agricultural Alternatives: Enterprise Budgeting for Small Farms and Homesteads."

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 finished, 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 Worksheets

• Sample Asparagus Budget - Establishment
• Sample Asparagus Budget - Second Year (Year after Establishment)
• Sample Asparagus Budget - Third Year
• Sample Asparagus Budget - Mature Production

Initial Resource Requirements

• Land: 1 acre
• Labor: 5-20 hours
• Harvest/grading/packaging: 25-300 hours
• Total capital investment: $7,000-$8,000

For More Information

Publications

Cantaluppi Jr., C. J., and R. J. Precheur. Asparagus Production, Management, and Marketing. Columbus: The Ohio State University, 1993. Available from estore.osu-extension.org.

Dunn, J., J. Berry, L. Kime, R. M. Harsh, and J. Harper. "Agricultural Alternatives: Developing a Roadside Farm Market." University Park: Penn State Extension, 2006.

Dunn, J., J. Harper, and L. Kime. "Agricultural Alternatives: Fruit and Vegetable Marketing for Small-Scale and Part-Time Growers." University Park: Penn State Extension, 2009.

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

Kime, L. F., J. A. Adamik, J. K. Harper, and C. Dice. "Agricultural Alternatives: Agricultural Business Insurance." University Park: 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." University Park: 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." University Park: Penn State Extension, 2012.

Maynard, D. M., and G. J. Hochmuth. Knott's Handbook for Vegetable Growers. 5th ed. Hoboken, N.J.: John Wiley and Sons, 2007.

MacNab, A. A., A. E. Sherf, and J. K. Springer. Identifying Diseases of Vegetables. Penn State College of Agricultural Sciences, 1983.

Mid-Atlantic Commercial Vegetable Production Guide. Penn State College of Agricultural Sciences, 2019.

Grower Association

Pennsylvania Vegetable Growers Association
815 Middle Road
Richfield, PA 17086

Authors

Revised by Elsa S. Sánchez, professor of horticultural systems management; 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.