Improving the Profitability - Adaptation of the High-Density Strawberry Production System for the Northeast

1995 Annual Report for LNE95-057

Project Type: Research and Education
Funds awarded in 1995: $96,204.00
Projected End Date: 12/31/1998
Matching Non-Federal Funds: $180,412.00
Region: Northeast
State: New Jersey
Project Leader:
Joseph Fiola
Rutgers University, Rutgers Fruit Research and Education Center

Improving the Profitability - Adaptation of the High-Density Strawberry Production System for the Northeast


Farmers in the eastern United States have traditionally grown strawberries in matted rows, but there is considerable interest in adapting the high-density annual systems now used in Florida and North Carolina. The late-summer planting system, based on integrated crop management (ICM) techniques, includes raised beds, black plastic mulch, and trickle irrigation, with plants spaced in staggered double rows. The late plantings afford relief from the heat, drought, weed and disease pressure of midsummer and the plastic protects against fruit diseases and eliminates herbicide use. The resulting early spring crop commands higher prices in the marketplace.

This project researched ways to increase the profitability and geographic adaptability of this plasticulture system. As a result, many commercial growers in New Jersey have already converted their acreage to this new method.

* Optimize an integrated strawberry production system involving genetic, cultural, and environmental aspects with improved profitability and decreased pesticide dependence.

* Investigate the influence of location, planting date, plant type, and floating row covers (FRC) on earliness, productivity, quality, and profitability.

* Compare selections (NJUS and MDUS strawberry breeding programs) and eastern adapted cultivars to ‘Chandler’ for pest resistance, earliness, productivity, and quality.

* Study the efficacy of poultry manure and chicken parts compost as the primary nutrient source, or as a replacement for fumigation.

* Study double cropping strategies with vegetables and renovation practices for maintaining the strawberry planting for a second production year.

* Extend research and development information on the system to encourage rapid commercial adoption.

Key Findings
Plasticulture profitability is 300% higher than matted rows. This method makes strawberries one of the most profitable crops on a per-acre basis.

Vegetable double cropping after strawberry harvest brought additional profits.

Eastern adapted cultivars and advanced breeding selections were high-yielding, large-fruited, and offered season extension over the variety standard, ‘Chandler.’

The clones showed excellent pest resistance, eliminating the need for all fungicides except Botrytis.

Organic nitrogen (N) nutrition was comparable or superior to conventional inorganic N. All organic N can be incorporated before planting, eliminating costs associated with mid-season fertilizing.

Methods and Results
As the agricultural value of land in the Northeast continues to loose the battle against the real estate development value of the land, the agribusiness industry is turning to high efficiency production systems that allow maximum profitability from the land. Plasticulture allows strawberries to be cropped as an annual. Second-year cropping and vegetable double cropping offer options to further increase profitability. This system has shown consistently high commercial profitability in southern New Jersey.

Though establishment costs are higher, the value of the early, high quality crop is greater. Labor costs are reduced — there is no setting of daughter plants or hand weeding, and the fruit is more easily and efficiently harvested from the beds.

The analysis showed that, if a commercial grower harvests 15,000 lbs per acre, sells the fruit for $2.00 per lb, with $13,362 in expenses (including harvest), the net is about $16,638 per acre. An average matted-row scenario of 10,000 lbs per acre at $1.33 with $7,811 in expenses equals $5,489 per acre net. The value of the fruit has been even higher in the “borderline” locations, and that has helped to rapidly spread the system to those areas. There are also a few organic growers in New Jersey and Maryland who are using the plasticulture system and marketing the fruit for double the commercial price.

The growth of the system in the region has simultaneously induced the beginnings a new nursery industry for tips and plugs specifically for the plasticulture system.

The plasticulture system is based on ICM practices that avoid and reduce disease and insect pressure. The system decreases the dependency on chemical pesticides by maintaining a microclimate that is not conducive to pest development, and by physically excluding pests from the susceptible plant material.

Black plastic mulch eliminates the need for herbicides and fumigation against weeds, since it blocks the light needed for weed seed germination and development. It also prevents the fruit from contacting the soil and reduces soil splashing onto the fruit, decreasing Botrytis fruit rot and leather rot. The raised bed allows greater air movement through the vegetative canopy, allowing for quicker drying of the dew and rainfall, thereby avoiding disease-promoting conditions on leaves and fruit. The beds also allow the soil to drain more efficiently, reducing or eliminating root diseases such as red stele and black root rot.

Plants are only in the field for a short period of time with this system, thereby avoiding many pest problems. Older plantings are more likely to encounter viral infections as they age because they have more chances to be exposed to vectors such as aphids and nematodes. Root weevils are eliminated as a pest since plants are removed immediately following harvest, thus removing their food source from the field. The annual system greatly reduces sap beetle problems, which are more prevalent in held-over matted-row beds. Plant trash is greatly reduced as leaves are much younger, greatly decreasing the inoculum source for Botrytis. Leaf spot cover sprays in the fall are eliminated as the growth is much younger and has not been exposed to inoculum during the heat of the summer.

Floating row covers (FRCs) are an integral part of plasticulture, increasing flower bud initiation in the fall, providing winter and frost and freeze protection, and promoting earlier fruiting. For ICM, FRCs also serve in avoiding insect infestations by physically excluding pests such as tarnished plant bug. Since the FRCs promote an earlier crop, they also serve to accelerate plant development past the susceptible stage before the pest emerges, as with the strawberry clipper. The degree of effectiveness is dependent on over-wintering habits of particular insect species, as well as environmental conditions, especially in the growing season previous to the harvest season.

At the core of ICM principle is the use of an innate genetic resistance to pests as the most efficient means of control. The NJAES and other eastern breeding programs have selections with excellent fruit flavor and size for fresh market production in the system. The genetic disease resistance and general adaptation of these varieties allows them to be grown with fewer fungicides. The selections have resistance to Red Stele and Verticillium wilt; therefore fungicide sprays for these diseases have been eliminated.

Currently the best option for the Northeast is the use of transplant plugs that are propagated from actively growing runner tips. The plugs, planted in late August and early September, were the standard for the system and offered the most consistent results; however, variety choices were limited.

These plugs are costly, at about $130 per 1000. A by-product of fresh-dug plants are the multiple-crowned mother plants. Two years of investigation revealed that the fresh multiple-crown mother plants were high yielding and were superior to conventional plugs when planted after the recommended planting dates. This plant type can provide a significant buffer for late planting opportunities in northern locations. FRCs applied in mid-October also compensated for late plug planting.

A critical issue facing strawberry growers involves the dependence of current strawberry production on agricultural chemicals for pest control. Eastern cultivars and advanced breeding selections were high-yielding, large-fruited, pest resistant, and offered season extension over the variety standard ‘Chandler.’ Advanced selections from the NJUS and MDUS breeding programs also performed well. Disease resistance of the selections was excellent, eliminating the need for all fungicides except for bloom sprays for Botrytis. Based on a combination of superior yield and fruit weight, the varieties ‘Allstar,’ ‘Noreaster,’ ‘Seneca,’ ‘Earliglow,’ and ‘Latestar’ are now being commercially planted in the system. The demand for these varieties has fostered the development of a new nursery industry in the region.

Another issue facing strawberry growers involves the contamination of groundwater supplies from the overuse of synthetic N fertilizers. Research showed the yield of organic N nutrition treatments was comparable or superior to conventional inorganic N plots. There were no differences in yield, primary, or average fruit weights with regard to N application timing. Results show that with organic N in a plasticulture system, all N can be preplant incorporated, eliminating the need for the increased cost, effort, and equipment necessary for spring fertilization.

Two alternative components are available for maximizing the profitability of this system: carryover beds for second year strawberry fruiting, and double-cropping with vegetables after the first or second strawberry harvest.

Our tests showed no differences in the organic versus conventional carryover beds. The eastern varieties were typically superior to ‘Chandler’ in second year plots due to superior disease resistance. In general, when yields of first-year beds are high, lower yields and smaller fruit are expected for the second year; when yields of first-year beds are low, high yields and good fruit size are obtained in the carryover beds. In practice, commercial growers have used carryover beds for pick-your-own and to wholesale a less expensive alternative to the fruit from the first-year beds. A significant portion of the experienced growers are now increasing profitability by maintaining the plantings for a second harvest season.

The success of vegetable double-cropping from 1995 through 1998 with tomatoes, peppers, melons, pumpkins, zucchini, or spaghetti squash depended on the specific growing season during and after strawberry harvest. In the warm seasons, when strawberry harvest was early, high yields of tomatoes, peppers and pumpkins were obtained. In the cooler seasons, when strawberries were late, the short-season zucchini squash was the best choice.

The flexibility of plant types, planting dates, varieties, N nutrition, second-year strawberry harvest, and vegetable double-cropping has improved the profitability of the system and allowed it to move into more northern locations. Grower adoption has increased rapidly in the region, with about 200 growers in the region currently using this system, up from about 20 in the early 1990s.

We can conservatively track the expanding commercial adoption of the system throughout the Northeast. Walker Brothers/Jersey Asparagus Farms (WBJAF) sold over a million tips and plugs to 109 commercial growers in 1997, and over 1.1 million tips and plugs to 138 commercial growers in 1998. Davon Crest Farms (DCF) sold about 575,000 plugs to 30 growers in 1997 and 575,000 again to 35 commercial growers in 1998. That is over 170 growers in 1998 from these two nurseries alone, and that does not include the significant number of growers who are using dormants. Both WBJAF and DCF noted that in 1998 many of the experienced growers were keeping the planting for a second year and that there were also many new growers trying the system for the first time. Scott Walker from WBJAF estimates he could have sold 50,000 to 75,000 more if he had the material. Many growers called very late trying to purchase plugs. He projects a potential 20% increase in plug sales annually, and that the demand for eastern varieties will increase dramatically in the future.

Site Information
The plasticulture system originated in the moderate California climate and has allowed close to year-round production in the state. From the 1980s through early 90s it has become the system of choice in the Southeast, and is practiced on over 1000 acres in North Carolina. University research has moved the system into the eastern shore of Maryland and Virginia as well as southeastern coastal New Jersey. The system has thrived where the soils are light and the climate is moderated by large bodies of water.

Research and commercial locations were chosen to optimize profitability and to expand the adaptation of the system.

Reported November 1998. 1999 Northeast Region SARE/ACE Report.


Robert Rouse

U. of MD
MD 21658
Joseph A. Fiola

Rutgers univ.
NJ 08514