Strawberry producers in the eastern United States primarily use spring bearing cultivars, which produce a crop for a relatively short period of time. Harvest is finished by the end of June; however, with large urban populations nearby, the demand for fresh strawberries is strong throughout the summer. Until recently the small size and poor quality of day neutral strawberry cultivars have prohibited day neutral strawberry production from filling a portion of this market. Many growers are looking for ways to produce fruit during the summer months to meet the demand by the consumers.
Through this project farmers were introduced to new varieties of day neutral strawberries, which have the potential to produce heavy yields of fruit with very desirable flavors. Producers were also introduced to a new method of producing strawberries: annual day neutral strawberry production. This production method involves producing a large sized plug plant from bare root day neutral strawberry plants in late winter. The plugs are then planted in plasticulture raised beds and fruited during the summer months for one year. In various research projects, first year production ranged from .5 pounds per plant to just over 1.8 pounds per plant. Fruit produced during the summer months has sold for as much as $5.00 per pound. Through the project over 350 participants in field days, conferences, short courses, etc. learned about producing day neutral strawberries. Of these 24 producers were identified that grew day neutral strawberries utilizing the new method of growing strawberries.
During the project, six field based research projects were conducted. These projects provided information to growers on the best nitrogen fertilization levels, plant propagation methods, growing techniques and variety selection. During the first year of the project organic nitrogen (compost) and nitrogen levels were evaluated to determine what level of nitrogen would produce the highest marketable yields and healthiest plants. In the second year of the project, research focused on the best method of propagating day neutral strawberry plants, runner removal and nutrition in carried over plants. In the final year of the project research evaluated varieties in variety trial plots and looked at production on different color plastic mulches. An eastern US everbearing strawberry production guide was based partly on the research this project.
Strawberries have been one of the most popular fruits for American consumers. Until recently fresh strawberries were only available during the spring June bearing strawberry season in the northeastern U.S.. More recently with the increased use of refrigeration and efficient trucking and production areas in California and Florida strawberries have been available in grocery stores throughout the year. Local Eastern US production of strawberries is minimal due to the short harvest season inherent in the use of short day varieties. While short day varieties are adapted to the eastern US, the short harvest season leads to lower yields (10 vs. 50 tons per acre) and a small marketing Lower yields and a brief (or inconsistent) supply results in lower presence in the grocery store or market in general. This has lead to a decrease in local production of strawberries in the eastern US.
Supporting the eastern US industry and grower have been two marketing phenomena, the pick your own marketing channel and more recently, the local food movement. In a bid to increase the health benefits from the fruits they eat and due in part to the poor quality of shipped berries, consumers have increased the demand for locally produced fruit. Some of this fruit is sold at farmers markets. Farmers at farmers markets are always looking for fruits and vegetables that are in high demand that they can market directly to consumers. Other growers wish to market to grocery stores, where a consistant supply of fruit is much valued. Where Florida and California can supply a longer harvest season, everbearing strawberries, with an unlimited production season, also can supply a the market for a comparable 3 to 5 months a year.
Everbearing or day neutral strawberry varieties have been available for many years. Varieties such as Tribute and Tristar were developed by the USDA and the University of Maryland in the early 1980’s. While these varieties were great improvements over other varieties available at the time, they still produced small fruit and were soft during the summer months. Not until the late 1990’s were day neutral varieties with large firm fruit from California and the United Kingdom starting to become available.. Unfortunately, there was little literature describing growing techniques to manage everbearers in the eastern US. These new varieties along with production methods from Europe serve as the basis for the production method employed in this research and education project.
The primary outcome of this project was to establish a day neutral strawberry production system in the cool climate areas of the northeast. Information gained through this project was presented through field days, strawberry short courses, and field walks held during the growing season. The plan was for 200 farmers to attend educational programs on growing day neutral strawberries. Farmers with interest in producing fruit were invited to attend strawberry short courses or field walks. 100 farmers were invited to attend a second educational event such as a strawberry short course or field walk. Of the farmers that attend the field walks or strawberry short courses, 20 were expected to add day neutral strawberries growing new varieties utilizing advanced growing techniques to their farming operation. All participants of the short courses and field days will be surveyed to determine who has added day neutral strawberries to their farming enterprises.
During 2006, the project established two research plots (one in Garrett County, MD and the other at Penn State’s Horticulture Farm at Rock Springs) to examine the nutrient needs of annual planted day neutral strawberries. Each site looked at nine nutrient levels created by overlapping three levels of compost (providing 0, 40, or 80 pounds of available nitrogen) and three levels of nitrogen applied through drip irrigation (0, 1, & 2 pounds of soluble nitrogen each week). Each plot contained three reps in a split block design. Dormant cold stored ‘Seascape’ day neutral strawberry plants were planted in 32 cell trays and were started in a greenhouse. The plants were held at a minimum of 10 degrees C until planting time. The plants were planted into a raised bed which was covered with an aluminized plastic. Aluminized plastic was selected to keep the soil as cool as possible during the growing season. Flowers were removed on the plants until the middle of June to promote plant growth. Fruit harvest began the first part of July and continued until frost occurred in the middle of October. Berries were harvested three times weekly and weighed and the number of berries was counted to determine fruit size. Leaf samples were collected four times during the picking season and analyzed.
During 2007, the project completed three separate research projects. The first project was conducted at Penn State’s Horticulture Farm at Rock Springs, PA. The first year everbearer field was carried over to determine the effect of the nutrient treatments on a second year planting. The research also provided information about yield on second year day neutral strawberry plantings. The second part of the research was conducted on two farms in Garrett County, Maryland. This experiment compared fall planting versus spring plantings. Two types of fall plants were established (plugs and fresh dug plants) and two types of spring plants (plugs and bare root dormant plants) were compared. One location was inside a high tunnel. The third part of the 2007 research project investigated the effect of removing flower blossoms after planting spring plug plants. This tested whether the general recommendation to remove the flower blossoms for one to four weeks after planting helped the plants grow more vigorously before starting fruit production and resulted in larger fruit size. Removing flower blossoms is a labor intensive activity. This research was carried out on two cooperating farms in Garrett County.
During 2008, the project completed two separate research projects. The first project was a cultivar trial of day neutral strawberries. The cultivar trial was conducted at two locations: Penn State’s Horticulture Farm at Rock Springs, PA and at the research farm of Five Aces Breeding LLC near Oakland, MD.
The cultivar trial was conducted as an annual day neutral planting. The main plant source used was plug plants which were grown in Maryland, originating as dormant plants that were trimmed and grown in plug plant trays for 2 to 3 months prior to planting. With the cultivar Evie 2 in the PA trial, dormant plants were also planted for comparison to plug plants. Due to wet soil conditions, plants in Pennsylvania were planted on June 6, 2008 which is late relative to a normal or desirable planting date, though the MD planting date of May 7 was more typical. In PA, plants were planted into a field that was amended with compost applied at a rate that was calculated to provide 60 lb of nitrogen per acre for the first year assuming a 10% mineralization rate. This rate also provided 190 lb/a of P2O5 and 270 lb/a of K2O, which exceeded the recommended amounts by 140 and 160 lb/a, respectively as based on soil test results. No additional fertigation of nutrients was used. In MD, plants were fertilized with MicroStart60 Pelleted Poultry Litter to provide 60 lb/a of N, 40 lbs P2O5 and 60 lbs of K2O and were also fertigated with 20-20-20 to provide 1 lb of N/acre/week. Plants were planted into raised beds mulched with black plastic. Plants were grown in staggered double rows with 12” between rows within each bed and between plants. Yields are given as pounds per plant, but can be converted to lbs per acre, assuming beds on 6’ centers by multiplying by 14,520. In PA, blossoms were removed from the plants until July 3 and in Maryland no blossoms were removed.
The cultivar used as the standard was ‘Seascape’ in both states, with ‘Tristar’ also included in Maryland. Other named cultivars tested were ones which have been tried on only a limited basis. Several advanced selections from Five Aces Breeding, one from the USDA, and one from North Carolina State University were included. The three “FAB” selections have Fragaria moschata in their background, which imparts a wide range of flavors to the fruit.
The second research project involved comparing day neutral strawberry fruit size and yield on three different colors (black, aluminized, and white) of plastic mulch. Black plastic mulches have been shown to increase soil surface temperatures around 50F. Black plastic mulches would be favorable for plant establishment during cool spring weather but may reduce production during hot summer weather. Aluminized reflective mulch has been shown to decrease soil temperatures by 2-4oF at 2-3 inches deep. . White plastic has also been shown to reduce soil temperature. During hot summer days, the cooler soil temperatures would be desirable for strawberry production. In Garrett County (2500 ft altitude plus) where the springs are often very cool and the summer temperatures are milder than in most other eastern US strawberry production areas, it is questionable whether strawberries produced on aluminized or white plastic will out yield strawberries grown on black plastic. Aluminized plastic also has a higher cost to the producer of about $400.00 per acre.
We established two research plots to compare fruit production of annual plug planted day neutral strawberries on three different colors of plastic mulch. The plants were planted in a typical 12 inch double row raised bed plasticulture system. Three twenty-plant blocks were randomly selected in each of the different plastic color rows. Soil temperatures were taken with a probe at 3” deep during each harvest time. The variety for the research was ‘Evie 2’ and the planting date was May 14th.
2006 Annual Day Neutral Strawberry Nutrient Research
In 2006, we were successful in establishing an annual day neutral strawberry research planting that produced fruit from July through mid October. Fruit production ranged from .4 pounds of fruit per plant in Maryland to 1.2 pounds in PA. This production is comparable to the production levels in Canada and are somewhat less than those in the United Kingdom (where planting date is much earlier). The average fruit weight at the Pennsylvania site was 11.7 grams for marketable berries and 10.6 for all fruit at the Maryland site.
In the nutrient study, no overall statistical difference was achieved when the results of both locations were combined between the nine nutrient levels. At the Garrett County site, a statistical difference occurred on the soluble fertilizer dripped through the irrigation. The 2 pounds of soluble nitrogen level produced .58(a) pounds of fruit per plant, the 1 pound of soluble nitrogen level produced .51(ab) and the 0 nitrogen level produced .44(b) pounds of fruit per plant (letters of significance at the 5% level) The number of berries produced was also significantly different with the 2 pounds of soluble nitrogen producing 1014(a) berries, the 1 pound of soluble nitrogen producing 906(b) berries, and the 0 level produced 794(c). The leaf analysis regression results using SAS PROC Stepwise MaxR improvement (r2=0.18,p(F) = 0.0004) in the best 4-element model for yield per plant yielded a significance for nitrogen (0.02) and potassium (0.01). This indicates that the statistical difference in yield was likely a result of the varying the amount of nitrogen and potassium. These two nutrients are important for plant growth and fruit sugar accumulation.
(See Figure 1 Nutrient Data)
2007 2nd Year Nutrient Research
For the experiment on compost rates and liquid nitrogen fertigation in a 2nd yr field at Penn State treatments consisted of compost at rates to provide 0, 400, and 800 lb of total N/acre (0, 40, and 80 lb of N/acre/year assuming a 10% mineralization rate) and 0, 1 and 2 lb of N/week/acre as 20-10-20 inorganic soluble fertilizer with micronutrients. Compost was applied in 2006 at planting. In 2007, fertigation treatments were applied once per week from May 22 through October 9.
Fruit production and harvest occurred in three relatively distinct flushes, the first occurring from May 23 to July 6, the second from July 20 to Aug. 31, and the third from Sept. 7 to Oct. 27. Yield data were analyzed separately within the three flushes to detect whether there were changes in the plants’ nutrient needs as the year progressed, and were also analyzed as totals for the year.
The early and mid-summer harvests were the largest, averaging 9985 and 9185 lb/acre in total yields across all treatments (approximately 0.6 to 0.7 lbs/plantat 15,000 plants per acre). The fall harvest was the smallest, averaging 6651 lb/a. During the first harvest flush, the only significant difference among treatments was that when the inorganic fertilizer rate of 1 lb N/acre/week was applied, the highest compost rate resulted in the highest yields. During the second harvest flush, in the no compost plots, both rates of fertigated N resulted in higher yields compared to no fertigated N. There were no significant differences among treatments within the third harvest flush.
There were no relative changes in treatment effects through the year, therefore the flush-specific effects were also found in treatment differences for total annual yield. In total yields for the season, when no compost was applied, applying either soluble fertilizer rate resulted in higher marketable, unmarketable, and total yields than if no N was fertigated. If compost at either the 400 lb or 800 lb total N/a rate was applied, there was no significant difference in marketable, unmarketable, or total yields among nitrogen fertigation rates, though yields numerically tended to be highest at the 1 lb N/acre/week rate. There was no yield improvement obtained by increasing the N to 2 lb N/a/week fertigation rate, whether compost was applied or not.
The highest compost application rate either produced or to tended to produce higher marketable, unmarketable, and total yields than either applying no compost or the lower amount of compost. Whether this yield increase is due strictly to nitrogen, other nutrients, or improvements in such factors as soil structure, aeration, or water infiltration is not known. The soil at this site is heavy with a large clay component. It appeared that the percentage yield increases that resulted from applying compost were greatest (25%) when no inorganic fertilizer was applied, even though the statistical significance was lower. This could indicate that was greater variability among individual plot performance when no compost was applied.
Percentage marketable fruit and mean berry weight was not significantly different among any of the treatments. Mean berry size was smaller in 2007 than in 2006, presumably due to a large number of branch crowns on the two year old plants.
The bottom line is that high yields could be obtained by applying the highest rate of compost alone with no need for additional inorganic nitrogen. If no compost is applied, an inorganic nitrogen rate of 1 lb of actual N/acre/week is sufficient to produce high yields. Both compost and inorganic N at 1 lb of N/acre/week may be applied for maximum yields, but the increases in yield relative to applying either N source alone are not likely to be economically significant. An economic analysis is underway to determine the most economical methods of producing the highest yields.
2007 Planting Time and Propagation Method for Variety: ‘Evie 3’
Fall plug plants and fresh dug day neutral strawberries were planted in mid September 2006. Spring planted plugs and dormant bare root plants were planted the first week of May 2007. The plants were planted in two 20 plant blocks on raised beds covered with plastic mulch.
Fall planted plants established well and were protected through the winter with heavy floating row covers in the outside planting. Fall planted plants planted outside started to fruit on May 29th as compared to spring planted plants which began on July 4th. At the high tunnel site, blossoms were removed on the fall planted plants until the spring plants were planted.
The yield difference between the four types of nursery stock were not significantly different (see 2007 Table 2) in the tunnel planting; however, fall plants did out produce the spring plantings in yield (weight/plant). Outdoors, the fall plug plants significantly outperformed the fall dug plants. Both types of fall plants outperformed the spring planted plants by a wide margin. The fruit size on the spring dug (dormant) plants was also significantly less than for the other planting methods.
These results indicate that planting fall plug plants should be a more productive method of growing day neutral strawberries. However, fall plantings will require more labor to protect plants from winter injury. Early spring yield from fall plantings may not happen each year due to late frosts. In the high mountains of the east, water for overhead irrigation for frost protection is difficult to obtain. Protection with floating row covers is feasible, but this also increases the costs of production.
At this time, fall plug plants are also not commercially available. A local grower is in the process of establishing a nursery for fall plug production. A tissue culture laboratory has been completed and initial production is expected to begin in 2011. The cost for the fall plugs is unknown at this time but is not expected to exceed that of spring plugs (about $.33 per plant). Early spring production from fall planted plants may also not provide as high a return on fruit production as fruit will be produced at the same time as with June bearing plants and a premium price will not be obtained.
From 2007 data, fall planted plugs will provide the highest yield potential for producers but may not provide the highest profit margin especially if mid winter cold injury occurs. Additional research needs to be conducted to determine the cost of production and anticipated returns on fruit production on fall versus spring plantings. The experiment also needs to be repeated at more locations and using different varieties. Yield from spring planted plants at both experiment locations was much lower than from other spring planted locations. In 2008, we continued to compare fall planted plugs and spring planted plugs. These data will help add confidence to our recommendations.
2007 Flower Blossom Removal
In this research, ‘Seascape’ day neutral strawberry plants were planted during the middle of May 2007. The plants were planted on raised beds covered with plastic mulch. Two parallel rows were planted on the top of a 30” wide bed with 6’ from the center of one bed to the center of the next bed. The plug plants were planted 12” apart in each row. After planting, three groups of 20 plants were randomly selected from each of three rows. Blossoms were removed until the following three different dates after planting.
Fruit production for the various treatments began on:
Treatment #1= remove blossoms until June 1st – first fruit ripe on July 2nd,
Treatment #2= remove blossoms until June 14th – first fruit ripe on July 10th,
Treatment #3= remove blossoms until July 2nd – first fruit ripe on July 17th.
While the treatments did have an effect on when plants started to fruit; treatments had no effect on total annual fruit production (weight/plant). The only significant difference found was that for mean berry weight at site 101 in Garrett County, Maryland. At this site, the mean berry weight was significantly lower for treatment #3. This result seems to be random and is contrary to that experienced in other everbearing regions.
(see Fig 2 Blossom Removal)
Producers need not remove flowers after the plug plants are planted in Spring. This will represent a savings in the labor required to establish spring planted day neutral strawberry plants. The only advantage to flower removal would be to delay fruit production to target a certain market. This research demonstrates that removing the flowers neither hurts or helps overall production; however, it should be noted that flowers were removed when plants were in the plug trays at the nursery. We continue to recommend flower removal at the nursery and from newly planted dormant bare root plants
2008 Annual Day Neural Strawberry Variety Trial
Yields in general were a bit low, which in PA could have been in part due to the late planting date, very hot temperatures soon after planting, and a somewhat shortened fall harvest season compared to previous years. In Maryland, the cold wet weather following planting also delayed peak production. Seascape yields, for instance, were only about half as high as has been obtained on average during 3 other years at both sites. Growing the plants on aluminized plastic rather than black also might have increased yields. Even so, considerable information was obtained on relative yield potential, fruit size and soluble solids, a measurement of sugar levels.
The three varieties with the highest marketable yield in the Pennsylvania trial were Everest (1.16 lbs per plant), Evie 3 (1.01 lbs per plant) and Albion (.68 lbs per plant). The three varieties with the highest marketable yield in Maryland were Seascape (.59 lbs per plant), EMF-f3 (.43 lbs per plant) and Evie 2 (.41 lbs per plant). Data was also collected on plant growth characteristics and disease and insect susceptibilities. Below is a description of each of the varieties in the trial.
Seascape: The current standard cultivar for day-neutral production in the eastern U.S. and Canada. Seascape is typically very productive, and produces medium-sized medium-red fruit with notable sweetness, but yields were low in this trial. Powdery mildew has been a problem in grower fields in some years.
Albion: Performed better in PA than in MD. Berries were quite firm and large – averaging 15.3 g over the season and over locations, which resulted in a higher percentage of marketable fruit. Reminiscent of Camarosa or Diamante. Similar to Camarosa in firmness, or just slightly softer. Perfect red color, with acceptably good, but not great, flavor when fully ripe. Despite vigorous plants, the size and fast picking of this berry makes it worth a try at least in small quantities. One potential problem is production of large numbers of runners.
Everest: Produced very high yields in PA but low yields in MD. The main problems with this berry are a smaller size, and it can be soft and lack flavor in warmer weather. Color is a bit light. In the cooler climates of western MD, its fruit has acceptable firmness and flavor. Flavor also improved during cool fall conditions, and some growers think its quality is acceptable. Everest produced the lowest number of runners of all cultivars and selections.
Evie 2: Improved berry size and flavor compared to Everest, but low yields in MD. Other characteristics (softness, shape, and light color) were very similar to those of Everest.
Evie 3: Produced high yields in PA similar to Everest. Quality was nearly identical to Everest, except slightly sweeter, but still soft with fairly small berries. This is a trial variety not available in the US.
Tristar: Only grown in MD trial. Yields were average and berries were small. Excellent flavor but the fruit is very soft.
FAB series: The soluble solids (sugar) readings for all of these selections were the highest of all cultivars in both PA and MD (data not presented for MD). Their unique flavors made them favorites for some taste testers, but also made them unacceptable to others. Insects also seemed to have a preference for FAB14 and FAB25. Of these selections, only FAB26 in PA produced yields that would be high enough to be commercially acceptable. FAB26 had a somewhat flattened shape.
EMF-F3: This cultivar produced large berries, but the yields were fairly low. Flavor and sweetness were below average.
USDA EB: Trialed only in MD. This cultivar had good shape, color, flavor and size. Would like to see this one again for more data or possibly in tunnels to extend the late season.
NCL 05-87: Plants were extremely vigorous but, remained vegetative and produced numerous runners well into the fall. Initially this was an effect of the plants being recently brought out of tissue culture, rather than an actual variety characteristic
(see Doc 1 Day-Neutral Variety)
2008 Colored Plastic Mulch Trial
Data collection from one of the sites was interrupted during the summer, therefore the data is only being presented from one site which did not allow for statistical analysis of the research. At the remaining site, however, increased production was observed on the aluminized plastic. The production per plant on aluminized plastic was 792 grams (1.75 lbs/plant) with an average berry size of 13.7 grams. Production per plant on white plastic was 743 g with an average berry size of 13.3 grams. The plants on the black plastic produced 689g per plant with an average berry size of 13.2 grams. Soil temperatures under the black plastic averaged 71.5oF which was lower than expected. This might be explained by the fact that the plastic was not tight to the bed due to rocky soil conditions.
Average soil temperature on the white plastic was 73.3oF and on the aluminized was 69.7oF. Early fruit production was slightly higher on black plastic during the later part of June and early July, however in mid summer, production on the aluminized plastic was greater.
The important question would be whether the additional cost of the aluminized plastic would be covered by higher yields as compared to black plastic. At a plant population of 15,000 plants per acre, an average marketability of 70%, and a value of $3.00 per pound, the value of an acre of strawberries planted on aluminized plastic would be $7,119.00 higher than that produced on black plastic and $3,385.00 higher than that produced on white plastic. From our observations the extra cost per acre of aluminized plastic ($400.00 per acre) would be a profitable investment. The disadvantage to growers of small plots is that they would have a higher initial investment in a roll of aluminized plastic that may be used for several years and that the aluminized plastic may not be available from local suppliers.
(see Fig 3 Colored Plastic Mulch)
From 2006 to 2008, personnel from the project held or participated in seven educational events discussing methods of growing annual day neutral strawberries. A total of 325 people attend these events. During that time the investigators also held five educational activities such as short courses, field days and twilight meetings focused on annual day neutral strawberry production. A total of 97 producers attended these activities. A total of 23 producers from West Virginia, Pennsylvania and Maryland have started growing strawberries using the annual day neutral strawberry production method. Of these producers 19 were new to raising strawberries.
From 2006 to 2009, the investigators shared information with producers and extension agents at 15 educational events which reached over 475 people. Events ranged from local field days and short course to regional producers meetings to the National Association of County Agricultural Agents Annual Conference. Presentation abstracts were published in three conference proceedings. A journal article entitled “Optimizing Day Neutral Strawberry Growth” was published in 2009 in the National Association of County Agriculture Agents Journal. The journal article is available on line at www.nacaa.com/journal/index.php. See Attached Doc 2 Journall of NACAA Day Neurtal Strawberry
Information from the project was also used to update The Mid-Atlantic Berry Guide for Commercial Growers (AGRS-097 Penn State University Cooperative Extension) 2010 section on ever-bearing strawberry production. The guide is revised biannually and distributed to 600 producers and extension educators throughout the mid-Atlantic region. Ever-bearing strawberry information was added as a new section in the Penn State Cooperative Extension publication (UA290) “Agriculture Alternatives: Strawberry Production” which was updated with information from the project.
The major publication produced by the investigators was a 69 page extension bulletin titled “Season-Long Strawberry Production with Everbearers for Northeastern Producers”, University of Maryland Extension EB401. The bulletin explains the history of everbearing strawberry production, production methods from this projects, and information from across the United States and world on everbearing strawberry production. The bulletin is available online at http://extension.umd.edu/publications/Category.cfm?ID=C#subCat19.
Additional Project Outcomes
Impacts of Results/Outcomes
The 2006 research project provided valuable information for local producers. The yields achieved at both sites for the annual production system were adequate to provide for a profitable enterprise. By producing fruit during the summer months, local producers should be able to achieve prices such as $3.00 per pint which results in an income of about $1.50 per plant. At a cost of about $.50 per plant, producers should make a return equal to about $15,000 per acre.
In 2007 to assist those interested in growing day neutral strawberries, the Garrett County Extension office worked with a local greenhouse to prepare and grow plug plants for spring planting. 13 farms planted over 20,000 day neutral strawberry plants in 2007. This resulted in new producers with over one acre of annual planted day neutral strawberries.
An end of season survey was sent to individuals that produced day neutral strawberries. Of the producers that responded, 100% indicated that they planned to produce day neutral strawberries in 2008. 85% indicated that they intended to keep production the same or increase production. Six producers responded to the question asking them to report gross income from strawberry production. These six farms reported gross income of $16,639.00 from 11,400 plants ($1.46 per plant).
In 2008, twenty-one farms planted over 20,000 day neutral strawberry plants. At the fall strawberry producer meeting, a survey was conducted to evaluate the effectiveness of the education and outreach of the SARE grant. Of the producers surveyed (n=14) 86% had not produced strawberries before the start of the SARE grant. These producers now have an average of 2.2 years of experience producing day neutral strawberries. The producers were asked to rate on a scale of 1 to 5 (1 equals very important and 5 equals little importance) the impact that six education/outreach type activities had on the success of their operation. The average rating was a 1.65, indicating that the participants felt the outreach activities were important to the success of their operations. The two education/outreach activities with the highest ratings were “education programs sponsored by the grant” and “technical assistance provided by extension”. Producers were also asked to rank their knowledge and skills with producing strawberries based on three questions before becoming involved with the grant and the same three questions after becoming involved with the grant. On a scale of one to five (1 equal to very knowledgeable and 5 having limited knowledge), the producers ranked themselves an average of 3.7 before and 1.9 after. The producers were also asked to report the number of plants producing fruit in 2008. Fourteen producers indicated they produced fruit on 16,500 plants. Eleven of these producers estimated their gross sales from strawberries were $18,863. While this is less than $2,000 gross income per producer, the average number of plants per producer was only 1,200 which is less than 1/10th of an acre. About 80% of the producers indicated that they would stay about the same size or increase production in 2009.
Most of the producers involved in this project were small sized producers that sell a variety of fruits and vegetables at local farmers markets and roadside stands. Local strawberries produced during the summer months are in high demand. Producers have sold strawberries for as much as $3.50 per pint which converts to over $5.00 per pound. At these prices and with .5 to 1.5 pounds per plant of production, it is easy to see that annual day neutral strawberries sold in small quantities at local farmers markets can be successful and profitable.
In order to determine whether annually planted day neutral strawberries could be a commercially produced and sold to wholesale markets, a budget was developed using $3.00 per pound as the selling price, one pound of production per plant and 70% marketable fruit. This gives a total income of $2.10 per plant. The total cost of production was $.89 per pound which included harvesting containers and labor for planting, management and harvesting ($4580 per acre). This leaves a profit of $1.21 per plant or over $18,000 per acre. A matrix of production levels and market prices is included with the developed budget. At $2.00 per pound and one pound of production per plant the profit would be $.73 per plant or just over $10,000 per acre. See attached spread sheet budget in Table 1 Day Neutral Strawbery Budget.
At the turn of the century, strawberry production in Garrett and surrounding counties was limited to a few pick you own operations. Mountainous terrain with very cold winters and short growing seasons has made strawberry production difficult. The annual day neutral strawberry project eliminated the spring frost=lost annual crop aspect of strawberry production and spread the production over the summer growing season, remember lack of ample water makes overhead irrigation based spring frost protection impossible in much of the mountainous region of the eastern US. For just the consistency of production most of the farmers that have adopted the growing system market their fruits and vegetables at local farmers markets. The producers have grown between 500 and 5000 plants. The strawberries have been used to supplement the income of existing fruit and vegetable sales. The strawberries have been a popular addition to the fruits and vegetables offered at farmers markets and have made producing fruit and vegetables on a small scale more profitable.
Areas needing additional study
Research and demonstrations conducted in this project have answered a sufficient amount of questions to allow publication of a production guide. Thus, many of the management topics: fertilization, planting date, mulching type, the use of tunnels, etc. require only regional adaptive or fine tuning research. Other management topics were not researched or research has not provided satisfactory answers.
In the summer in warmer areas, high temperatures reduce yield, fruit size and fruit quality. No research on evaporative cooling, the use of infrared excluding plastics in tunnel coverings, and shade cloths, has been found but may be fruitful. The use of earthtubes or other geothermal cooling may also provide hundreds of cubic feet of 70F air per minute in mid day in the middle of the summer from 100 ft long non-perforated drainage tubes buried 6-8 ft deep in the ground. The use of winter-harvested ice to cool circulating water in radiators in tunnels may also be combined with other methods, eg. shadecloth, to provide summerlong fruit in areas like Ohio, New Jersey, Maryland and so. Pennsylvania.
Fall planting was more fruitful than spring planting; however, outside of Quebec, suitable fall planting stock is unavailable. This is partially due to the slower runnering (plant making) of day neutral plants. It is also partly due to the need to plant early (September) in the cooler areas of the eastern US which are well adapted to everbearing strawberry production. Research should center on source or mother plant type and management (hormone applications, the use of tissue culture plants, pot type, fertilization) for greater and earlier runner production. A small nursery with a tissue culture lab (Five Aces Breeding) in Oakland Maryland will conduct some of this research and will provide the information on its website: www.fiveacesbreeding.com in the next several years.
Varieties developed for everbearing production have been produced in California, the United Kingdom and the European Union. Climatological differences between most of the eastern US and these strawberry growing regions are significant. Peak summer temperatures are often higher here, and more importantly, leaf surfaces can be maintained during the winter in the other locations. Yet, yield differences between the strawberry-growing regions and the eastern US are partly due to length of growing season. These differences make breeding in the eastern US one of the highest priorities for expansion of the everbearing strawberry industry. While it may seem that pest pressure may be higher in the eastern US, pests are common in the major strawberry growing regions too. Therefore, breeding should concentrate on early yields, more consistent fruit quality and large fruit size. Pest resistance, while important, should be left to later efforts.