Strawberries are a popular variety of berry enjoyed all over the world. They are used in a variety of applications, from fresh consumption to being used in desserts, drinks, consumer packaged goods, and even used as an ingredient in skincare products. This page focuses on field strawberry production.
Market Size
Global Strawberry Production
According to Food and Agriculture Organization of the United Nations, the world production of strawberries in 2021 was 9.175 million tons, with production led by China, the US, Turkey, and Mexico. In 2021, the global strawberry crop was produced on approximately 390,000 hectares. This FAO data includes strawberries for all uses, including fresh consumption and processing. The data combines field strawberry and table-top berry production.
Country | Production, 2021 (tons) | Production Value, 2020 ($USD) | Area Harvested, 2021 (hectares) | Yield, 2021 (hg/ha) |
China | 3,380,478 | 10,154,243,000 | 129,046 | 262,668 |
United States | 1,211,090 | 2,560,795,000 | 19,992 | 605,787 |
Turkey | 669,195 | 367,726,000 | 18,676 | 358,318 |
Mexico | 542,890 | 498,959,000 | 11,905 | 456,016 |
Egypt | 470,913 | 286,786,000 | 12,579 | 374,369 |
Spain | 360,570 | 338,420,000 | 7,220 | 499,404 |
Russia | 237,200 | 442,885,000 | 35,466 | 66,881 |
Brazil | 197,000 | N/A | 5,084 | 387,506 |
South Korea | 193,851 | 780,509,000 | 6,117 | 316,895 |
Poland | 162,900 | 139,941,000 | 33,900 | 48,053 |
Source: FAOSTAT and FAOSTAT Data Value of Ag Production
Production share of Strawberries by Global region in 2021 (FAOSTAT):
Controlled-environment or partially controlled-environment strawberry production is becoming increasingly popular, especially in Europe. However, despite continued growth in the practice of “table top” production in particular, there are still tens of thousands of hectares in field strawberry production across northern Europe, central Europe, and especially in southern Europe where temperatures rarely drop below the freezing point. The most prominent users of greenhouses and table-top production in the EU are Belgium and Netherlands, where this practice still represents less than a quarter of total product. Though this is an area worth watching for technologists hoping to serve the strawberry market in the future, field-grown strawberries are vastly more common globally and thus the primary focus of this page.
Domestic (US) Strawberry Production
According to the US Department of Agriculture, US growers produced 1.335 million tons of strawberries in 2021. The Ag Marketing Resource Center puts that figure higher at 26.7 million hundredweight (2.67 billion pounds) of strawberries valued at more than $3.42 billion. In 2021, the average grower price for fresh strawberries was $143/hundredweight. Within the US, most strawberries are grown in southern California or Florida, though some amount of strawberries are grown in every state in the US. Approximately 49,400 acres in the US are currently in strawberry production.
Source: Produce Blue Book
California is responsible for approximately 91% of the US’s strawberry production in the 2021 season, with Florida producing approximately 8% primarily in the late fall and winter months. Other states including New York, North Carolina, Oregon, and Washington produce most of the remaining.
Domestic (US) production by state 2021 according to USDA NASS metrics.
State | Production (in $) | Production (in CWT) | Yield (Cwt per Acre) | Acres Harvested |
California | 3,023,230,000 | 24,200,000 | 620 | 39,200 |
Florida | 399,010,000 | 2,500,000 | 240 | 10,400 |
Source: USDA National Agricultural Statistics Service
The California Strawberry Commission’s Acreage Survey proposes that the total acreage of strawberry farms in CA was 40,285 in 2023.
Strawberry production has been on the rise in the last two decades due largely to an increase in domestic demand for fresh strawberries and an increasing variety of strawberries that allows for a wider production season. In California and Florida, strawberries are grown and harvested essentially year round.
Source: USDA ERS
Top Strawberry Varietals In the US
There are dozens of varieties of strawberries available to growers, each with different attributes that might make it the right fit for particular soils, growing conditions, or markets. See UC Davis’ Breeding & Research Program or PennState Extension for a full list of available cultivars and with notes on appropriate planting conditions. There are several types of varieties among the most popular commercial selection which include:
- Everbearing: These varieties produce late spring and late summer or early fall crops, and otherwise there is little flowering or fruiting throughout the year. Everbearing varieties include Ozark Beauty, Sequoia, Ogallala, and Ft. Laramie.
- Day-Neutral: Often considered a more improved and productive type of everbearing variety, day-neutral strawberries flower regardless of the length of darkness, though can be highly sensitive to extreme heat. They can therefore produce buds, fruits, and runners continuously if the temperature is between 35 and 85 degrees Fahrenheit. Varieties include Albion, Aromas, Diamante, Hecker, Monterey, Portola, San Andres, Seascape, and Tristar.
- June-bearers or Short Day: Short-day varieties cannot flower without a sufficient amount of darkness. Short-day strawberries only produce buds in late summer and fall and then fruit and flower the following late fall, winter, and especially spring (varies based on geography). These varietals tend to produce larger berries and are popular with commercial growers. June-bearer varieties include Chandler, Douglas, Camino Real, Camarosa, and Shuksan. Some non-June-bearer short day type strawberries include;
- Midseason: Varieties include Allstar, Archer, Seneca, and Totem.
- Late season: Varieties include Rainier.
- Late-midseason: Varieties include Benton, Canoga, Jewel, and Clancy.
- Early season: Varieties include Mohawk and Northeaster.
- Early-midseason: Varieties include Honeoye, Itasca, Tillamook, and Darselect.
Addressable Market
According to MarketWatch, the Global Fresh Strawberry Market is estimated to be worth $18.37 billion USD in 2022 and is forecasted to grow to $23.21 billion USD by 2027 at a CAGR of 3.4%.
According to the USDA, the total (sales) value of strawberries production in the US in 2021 was $3.42 billion. US producers exported $544 million worth of fresh strawberries (521 million pounds) in 2021, representing the largest growth category among US fresh fruit and vegetable exports, with significant quantities destined for Canada, Mexico, and Saudi Arabia.
Due to rising demand, US strawberry producers have significantly increased production in recent years, from 1.77 billion pounds in 2016 to 2.17 billion pounds in 2021, representing a 23% increase. In the US in 2021, imports accounted for 19% of the total supply.
The true addressable market for strawberry production technologies will be approximately equal to the cost of labor needed to manage and harvest strawberries. So to determine the value of a specific technology to the citrus sector, it’s necessary to understand the costs associated with strawberry production.
Grower Challenges and Key Opportunities
Grower Challenges: Production
Successful strawberry growers manage a complex production system that takes careful and continuous management over a variety of shifting plant-life stages. Strawberry production requires significant land preparation, pre-planting preparation, and irrigation in most of its key production regions. Understanding the existing metrics and practices used by strawberry growers is important because it sets the target for the product development roadmap.
The vast majority of strawberries grown in the United States are grown in California. Growers in different geographies will face challenges unique to their climates and geographies, but many challenges are common among all strawberry producers. For much for this section, there will be a particular focus on California growers.
Strawberry season is year round in California, with different sub-regions reaching peak harvest at different times of the year. The three main growing regions in California are Watsonville/Salinas, Santa Maria/Oxnard, and Orange County/San Diego.
- Prior to planting strawberries, growers must prepare the ground, usually through a combination of tillage, fertilization, leveling, and irrigation to assure the soil is properly amended and for healthy and robust berry growth. After the preparation process is complete, fields will undergo final preparation as beds are shaped and drip irrigation tape is installed.
- Planting configurations and bed layouts can vary from operation to operation and are sometimes customized to fit the unique soil, geographic, and climatic conditions of unique farms.
- Non-organic growers will likely also prepare to deal with arthropods, soilborne fungi/disease, nematodes, and some weeds with pre-plant soil fumigation. This process is usually carried out by a custom operator, and can be costly. Growers must also obtain a per acre fumigation permit.
- Raised beds will then be covered with a colored plastic that helps retain soil moisture, prevent diseases and weeds, and keep the fruit from coming into contact with irrigation and/or fertigation water. The planting method is called Annual Hill Production (AHP) systems or strawberry plasticulture. Before starts are planted, a slotting implement is used to open the plastic cover at appropriate intervals— which is usually in the range of two rows, 12 inches apart, or about 22,000 plants per acre.
- Planting requires approximately 50 hours per acre of labor.
- Virtually all commercial strawberries are grown from starter plants, rather than seeds. Starter strawberry plants can flower within days and begin fruiting within weeks of establishment. Although strawberry plants are perennials, they are commonly grown for only one season to help with disease control.
- Between 5-10% of the field will likely need to be replanted over the course of the season due to poor establishment, gopher damage, and other issues.
- According to cost studies in California in 2021, combining all pre-plant activities and costs, producers will likely invest between $12,000-$16,000 per acre during the establishment and planting process alone.
- The pest management strategy on a given strawberry farm is likely to be carried out or supported by a Pest Control Advisor (PCA). These experts write pest management recommendations and help monitor fields for production, nutrition, and pest problems.
- Runners are horizontal stems that grow along the ground. Left unchecked, each runner produces new “daughter” plants attached to the “mother” plant. In production strawberries, these runners are managed to ensure that the plant’s energy goes towards producing berries and that the strawberry plants stay in their rows.
- Weeds and runners are sometimes managed with crop protection chemistry. On other operations, particularly organic farms, and at certain times of the year, weeds and runners are managed mainly by hand.
- Hand weeding and runner removal is estimated to require approximately 20-34.5 hours/acre/month for 10 months (the entire production season).
- Rodents, particularly gophers, can do a lot of damage to plants and infrastructure in strawberry fields. They are often controlled through trapping and poisoning programs, and may add additional labor hours per acre each season.
- Insects and mites are common issues in strawberry patches (see disease and pest sections below for additional specifics). Non-organic growers have access to a range of pesticide and fungicides, and pre-plant soil fumigation in particular, to use when dealing with diseases, insects and mites, though they may also use some organic methods, include tools like a bug vacuum, biological controls like the release of predatory mites, and the application of organic-safe control products like micronized sulfur. In some cases, the culling of diseased fruit by hand is the main way to eliminate disease issues.
- Growers may opt for additional sprinkler irrigation immediately after planting to ensure that plants have the best opportunity to establish.
- Throughout the growing season, strawberries are drip irrigated 2-3 times per week, though the amount of water needed will differ substantially by area, weather, soil type, well depth, and field conditions.
- Between February and September, growers will likely apply fertilizers and amendments through the drip irrigation (fertigation) system based on soil and crop needs. These inputs will provide the necessary NPK and micronutrients needed for production and plant health. While conventional growers often use synthetic NPK and micronutrient amendments, organic growers' fertilizer use will be from compliant inputs for organic production (e.g., liquid fish fertilizers, seaweed extracts, compost teas, etc.).
- Strawberries can be harvested in most months of the year, but most commonly in California are harvested between April and October, with peak harvest occurring in June and July. Berries should be picked when temperatures are cool, either in the morning or evening.
- Each member of a hired work crew will use a push cart that holds trays of eight, 1lbs clamshells down furrows, hand harvested and packed as they go along. A worker will harvest roughly three trays per hour early and late in the season when fruit loads are light, though during peak season a worker might load five or eight trays per hour.
- Strawberries are picked by hand and packed directly from the field into clamshells, and workers will make several pass through the same field, often within the same week.
- Harvesting is done based on size and color, and workers leave the less colored berries for when they return to the field later. Color is the primary indicator of maturity, especially because strawberries don’t continue ripen after harvest. Strawberries must be picked and handled very carefully. The fruit must be firm, well-colored, and free from rot.
- In addition to workers, a field crew will include a foreman, a fruit checker, and one card puncher who ensures proper harvest and tray counts for each worker.
- Trays are accumulated at a truck in the field. A truck loader stacks harvested trays on the truck and a driver delivers fresh berries to a cooler.
- Growers pack 110 trays per pallet for shipping and distribution, though the number of trays per pallet may vary by container type.
- When harvested at the right time and handled properly, strawberries will remain in good condition for a few days. Proper post-harvest handling of strawberries is essential. Pre-cooling the fruit immediately to reduce field-heat extends shelf life significantly.
- Optimum storage temperature for strawberries is between 32 and 34 degrees Fahrenheit, with 90-95% humidity. Under optimal conditions, strawberries can be stored for 5-7 days. Mold growth is accelerated above 36 degrees.
- The overall size and scale of the farming operation, and what other crops/varieties the farmer grows.
- Whether the land is owned or managed by the grower.
- Infrastructure availability (road access, irrigation systems, building locations, etc.
Grower Challenges: Economics
Common Strawberry Farm Business Model
Strawberry growers sell fresh berries for consumption, freezing, and processing to wholesalers, retailers, and other buyers. The success of the business will depend on the yields achieved, the quality of produce, the price, and the distribution networks they are able to access. Additionally, growers must consider other costs such as labor, fertilizer, and pest management, land costs (including land rent if leasing), as well as the potential for unexpected weather or market conditions.
There is also a growing interest in organic strawberry production in the US, as demand for organic berries grows and organic premiums remain elevated. Today, about 10% of strawberries produced in the US are organic, while about 90% are conventional.
There are a few different channels that growers commonly use to deliver strawberries to market. The most common is to contract the sale, with a price per unit and total quantity determined in advance of harvest. These contracts may be with wholesale produce packers, shippers, or directly with retailers (especially in the case of larger farmers, packing and shipping functions may be carried out by the grower). Alternatively, growers can take (most commonly, excess) fruit to a terminal market, where they are sold based on a shifting and localized market price in bulk. Finally, strawberries can be sold directly to consumers through on-farm sales, U-pick operations, or farm stands, though a very small amount of the total US crop is moved in this fashion.
The yield of the average acre of strawberry can vary significantly based on a number of factors, especially geography. According to USDA NASS, the average yield per acre for strawberry growers in the US in 2021 was 27.02 tons (~54,000 pounds US), though that figure can range dramatically by region, with California growers yielding 650 CWT/acre, and Florida growers averaging 290 CWT/acre.
Many factors also determine the current price per unit of strawberries, and thus predicting net revenue is not possible to generalize. The price that a producer receives is dependent upon variety, timing, quality, size, and other market factors, with higher prices general seen during the early and late season. Specific quality standards vary by geography and purchaser. Most strawberries produced in the US are consumed fresh with less than 20% processed for alternative uses. The price received for processing strawberries is less than half that received for fresh market strawberries.
Strawberry Crop Budget
We highly recommend taking time to understand crop budgets before having a conversation with a strawberry grower to better understand their needs and costs.
- Crop Enterprise Budget Example #1: Fresh Market Strawberries | Central Coast Region (Santa Cruz & Monterey Counties)
- Crop Enterprise Budget Example #2: Organic Fresh Market Strawberries | Central Coast Region (Santa Cruz, Monterey, and San Benito Counties)
- Florida Strawberry Production Costs and Trends
- Strawberry Economics in the Willamette Valley (Oregon) | Comparing Costs and Returns for Strawberries
It is critical to understand that farm economics and budgets vary widely between individual farm operations, and annually as a result of a landscape of factors, from water availability to input costs.
Regionally, costs of production also vary considerably. One estimate put per acre cultural costs in California around $22,000/acre, with an additional $66,000/acre in harvest costs. Many different factors contribute to the cost variations, though notably, in these estimates, labor costs where very similar.
Strawberry Costs
Though there are many, fairly standard expenses on in a strawberry operation, the magnitude of related costs varies widely based on geography, climate, cultural practices, and many other factors.
- Land (rent or purchase)
- Property alterations (like laser-leveling prior to grove planting)
- Irrigation systems (including installation)
- Initial start plantings
- Production and harvest equipment, facilities, and vehicles
- Water (generally calculated per acre-inch)
- Replacement plants (5-10% annually)
- Energy and fuel costs
- Equipment/facilities maintenance
- Inputs (including fertilizer, pesticides, and other crop protection, etc.)
- Auditing, compliance, and inspections (often charged either per tray or per acre)
- Property taxes
- Insurance
- Throughout the US strawberry industry, labor is often contracted out to a labor crew. More on labor costs below.
- Additional harvest-related costs include transportation and cooling, assessments (i.e. the California Strawberry Commission charges a per-tray assessment for research and marketing activities, currently $0.045/tray, split between grower and shipper), sales and marketing costs (varies, often between 5-10% of selling price), and post-harvest cleanup.
- Other costs include participation in food safety and regulator programs, which include inspections and employee trainings, which combined may add hundreds of dollars per acre in additional costs.
- Field sanitation; which includes the provision of hand-washing stations, drinking water, and toilets, also add additional costs, though those costs will vary substantially depending on the size of the labor force.
- Labor is a major expense on most strawberry operations balance sheets. According to the UCANR cost study, labor can represent 45-50% of total costs.
- A farm’s labor force is usually composed of a mix of salaried managers, directly hired full-time, part-time, and H-2A temporary workers, and indirect laborers who work for a hired labor/harvest contractor. Additionally, growers may also hire contracts like pest control or crop protection advisors, accountants, and others.
- In California, minimum wage for agricultural workers is $15.50 an hour, with additional requirements around overtime and days off. Actual labor costs as predicted by UC Davis in California strawberry operations is around $29/hour for machine operators and $21/hour for general laborers, including employers’ share of federal and state payroll taxes, workers’ compensation, and other benefits. The basic hourly wage is around $19.50 for machine operators and $14.50 for harvest workers.
- Based on estimates of harvest labor costs, an acre of strawberries in California demands about 2,500 worker hours during harvest alone.
- In Florida, minimum wage for agricultural workers is $10.00/hour, though industry observers indicate that most of the Florida citrus crop is harvested by H-2A workers, who are subject to being paid the current Adverse Effect Wage Rate (AEWRs) of $14.33 as of January 1st, 2023. Sponsors (farmers or labor contractors) must also pay for housing and transportation for H-2A workers.
- Most workers are paid piece rate wages ranging from $1.75 to $2.25 per flat, where a flat can contain either 12 12-ounce pints or eight one-pound clamshells. Worker incentive schemes differ between operations, with some growers offering workers an hourly wage of $5 an hour plus a piece rate of $1.25 to $1.50 for each flat, with others guaranteeing the minimum wage and offering $0.50 to $0.75 per tray after 8 trays picked per hour. Experienced workers typically pick 8-12 flats an hour, enabling most to achieve piece rate earnings that exceeds the minimum wage by at least $2 an hour. The average earnings were $604/week for strawberry workers in 2018.
Key Pressures on Strawberry Growers
Strawberries are one of the most labor-intensive crops grown in California, requiring an average of ~1.5 workers per acre and a total of 50,000 to 60,000 workers to harvest strawberry fields twice a week during the peak season. Labor is the major cost of growing strawberries, representing 50-60% of variable production costs.
California strawberry growers can pay more than $35,000 per acre per year in wages to the workers who pick their berries. That means that the there is an approximately $1.5 billion dollar strawberry harvesting market in California (using the CA Strawberry Commission acreage value).
Some workers monitor yields to determine where they are most likely to maximize their piece-rate earnings, and change employers to pick in the fields with the most berries to harvest. The overall labor shortage, coupled with this dynamic, incentivizes growers to pay competitively and to experiment with various employee incentive and retention schemes, which can include collaborative harvesting solutions, like transport platforms.
Mexico in particular has become a key competitor to the US in strawberry production, especially in competition with Floridian producers. Lower costs of production in Mexico, combined with a similar growing season, have made Mexican imports a key price pressure for US growers. Strawberry acres in the US are increasing, however, despite pressure from abroad, mostly in response to growing demand.
In recent years, costs have been rising across agricultural production, but especially for strawberry growers when it comes to packaging, farm inputs, labor and transportation. Strawberry production can be a margin-sensitive business, and when inputs rise, profitably can decrease substantially, even below the cost of production.
Strawberry Grower Interviews
- Check out this interview with Anthony Reade, Head of Berry Production at Betteravia Farms. He discusses what to know about the strawberry season and key challenges strawberry growers face when evaluating technology for adoption. He discusses successes and failures when it comes to harvest automation and harvest aids, why it’s so difficult to automate weed management, runners, and deblossoming tasks, and what opportunities he sees in the realm of water management, data collection for forecasting and identification tasks, and non-chemical pest management and crop protection. Finally, he offers advice for working with growers in the strawberry sector and what he expects from labor-saving technologies.
Interview here:
Consideration for Automation/Mechanization
Automation offers a potential solution to key challenges in the strawberry production sector. Automated harvesting, pest and runner management, deblossoming (removing a subset of blossoms on flowering plants), water management, and data collection could all have significant impacts on the efficiency and profitability of strawberry production. For further discussion on the existing need for these kinds of technologies, and the tools that exist today to do or assist in these tasks, listen in to the Interviews with Strawberry Growers above.
However, ensuring accuracy and speed in robotic operations is crucial for successful implementation and maximum efficiency. Agricultural robots, specifically strawberry picking robots, are seen as a way to increase productivity, reduce costs, and ensure the survival of the industry.
Accuracy
Accurate berry-picking is essential for optimal yield and minimizing waste. Harvesting robots need to be able to differentiate between ripe and unripe berries based on their color, size, and firmness. Strawberry picking robots, equipped with machine vision software and sensor arrays, can identify ripe berries with a high level of accuracy. However, many existing robots still struggle with accurately assessing the ripeness of strawberries, leading to inefficiencies and potential damage to the fruit.
Careful and Delicate Handling
The ability of equipment to pick strawberries without causing damage to the plant or the fruit itself is critical. The grip strength and precision of the robotic arms need to be finely tuned to handle the sensitive skin of strawberries. Gripping too tightly can lead to bruising or crushing the berries, while gripping too loosely can result in dropping or otherwise damaging the fruit during the picking process.
Adapting to Complex Environments
Strawberry plants can present a complex and dynamic environment for robots. The plants grow close to the ground, making it challenging for robots to navigate and maneuver effectively. Additionally, variations in lighting conditions (due to leaf shadow, different solar positions, etc.), different ripening stages of berries, and foliage density require robots to adapt their picking techniques accordingly. Developing robotic strategies that can handle these complexities is essential for achieving higher accuracy rates and to avoid missing any obscured berries.
Significant advancements have been made towards mechanical, autonomous harvesting in controlled environment setting, namely in greenhouses. However, much less progress has been made in field settings, where the vast amount of strawberries, in the US and around the world, are grown.
Speed
Efficiency and speed are critical factors in successful automation. Harvesting strawberries is a time-sensitive task, as the fruit can become overripe in a matter of hours. Therefore, the technology used in robotic systems needs to be fast enough to keep up with the demand and efficiently harvest the strawberries within the optimal timeframe.
Speed can be affected by various factors, including the tool’s movement capabilities, the processing speed of any digital systems, and the overall design and efficiency of the harvesting mechanism. Achieving high-speed automation without compromising accuracy is a significant technical challenge.
Cost
Though strawberry picking equipment has the potential to offer significant cost-savings to growers overtime, if the upfront cost of a technology is too high, they simply will not be able to make the investment. As organizations imagine and create autonomous and mechanized harvesting tools for the strawberry industry, grower cost constraints and ability to pay should be carefully considered.
Other Information to Consider
A recent study from the CA Strawberry Commission, “The Economics of Automation in Strawberry Processing: Feasibility and Potential Implications,” assesses the viability of automated calyx removal in strawberry processing. Using a mathematical model, it identifies optimal fruit purchasing strategies and highlights potential savings with the AVID automated calyx removal machine. Market trends suggest increased feasibility. Challenges include substantial equipment investment, potential job displacement, and the need for training. Adoption could reshape supply chains and impact strawberry varieties favored for processing.
“The technology of the strawberry picking robot has three main components. First, the strawberry data collector collects information about the location of the strawberries by scanning both above and below the strawberry leaf canopy. Second, the mobile platform moves at a programmable rate and serves as support for the picking arm and harvested strawberries/supplies. And, thirdly, the stereo vision camera which provides the required “visual” data to the arm so it can pick the correct strawberries.”
According to “The Economic Feasibility of Robotic Harvest in California Strawberry Production,” from the CA Strawberry Comission, Public information on the costs and operational expenses of robotic harvest systems is notably absent. Crucial metrics like harvest efficiency and field speed, essential for assessing economic feasibility, are also lacking. This uncertainty extends to how the adoption of these systems by certain growers might influence the broader labor market for manual harvesting crews, a cornerstone of the strawberry industry.
Should major producers embrace robotic systems, potentially reducing their reliance on human pickers, the labor dynamics for other growers could shift. The decrease in labor demand might alleviate labor-related challenges for non-adopting growers. This, in turn, could curtail their motivation to invest in automation, potentially slowing the overall rate of adoption.
A notable advantage of robotic harvest systems lies in their capacity to collect intricate data on plant health, diseases, and pests. This data, with high-resolution precision, can significantly refine the management of strawberry crops. This aspect underscores a broader potential benefit of these systems beyond just efficiency and cost-effectiveness.
- Research on improving machine vision algorithms, sensor technologies, and gripper designs to enhance the accuracy of identifying ripe strawberries and optimizing the picking process
- Advancements in robotic movement capabilities, such as faster arm motions and efficient navigation between strawberry rows, are being explored. Additionally, integrating automated vehicles to transport robotic arms between indoor strawberry rows can help increase overall efficiency and speed in large-scale operations
- The ultimate goal is to develop robotic systems that can reliably and efficiently harvest strawberries at a competitive rate compared to human labor. Achieving this will not only address labor shortages and reduce labor costs but also contribute to improved sales, reduced waste, and increased yields in strawberry farming.
Consideration for Pests and Disease
- Twospotted Spider Mite - The twospotted spider mite damages strawberries through the stippling, scarring, and bronzing of the leaves and calyx. They interrupt photosynthesis and are especially damaging during the first 4 to 5 months following transplanting, significantly reducing berry numbers per plant and overall yield. This pest can be managed by using vigorous cultivars, chilling plants, crop rotation, dust reduction, predator mites and general predators, or alternating chemical miticides.
- Lygus Bugs - Lygus bugs cause irregularly-shaped, cat-faces strawberries. They damage fruit by puncturing individual seeds, stopping the development of the berry in the area surrounding the feeding site. These pests are less common where the fresh market berry harvest is complete by the end of May (like southern California). These pests can be managed by weed control, vacuuming, biological controls, and chemical treatments.
- Cyclamen Mite - The cyclamen mite is an important pest of central coast strawberries. When infected, leaves become stunted and crinkled, with a compact leaf mass in the center of the plant. Flowers are fed on, and fruit on infested plants is dwarfed, with seeds standing out over the flesh of the berry. This mite can prevent plants from producing fruit. This pest can be managed through precautions in transportation, crop rotation, dust reduction, general predators, chemicals, and a high rate of water per acre.
- Aphids - Aphids damage berries in all growing regions, but is less critical in the central coastal region. Aphids leave white skins stuck to fruit, rendering it unmarketable as fresh fruit. Additionally, they transmit several viruses that can cause significant economic losses in perennial strawberries. Aphid control is also critical in strawberry nurseries to reduce virus transmission. These pests can be controlled through plastic covers, dust reduction, parasites and predators, and chemical treatments.
- Root Weevils - Root Weevil larvae feed on strawberry roots, destroying bark and cortex of larger roots, and causing plants to wilt. They were managed with the use of methyl bromide, but now the chemical is being removed from the marketplace. These pests can be controlled through crop rotation, sticky barriers, weed-host control, soil fumigation, and chemicals.
- Western Flower Thrips - Thrips damage has increased in recent years, impacting yield and quality. Fruit can become seriously discolored, and thrips can cause stigmas and anthers to turn brown and wither. Fruit can also russet around the cap. This pest can be controlled through weed control, predators, and chemicals only when thrips become very high.
- Cutworms - Cutworms can cause serious damage to the plant crown, and pronounced holes in fruits. Damage first appears as small, webless perforations in newly expanding crown leaves. Then, stem cutting and hole chewing occurs, more intensely in fields with bug vacuum usage. These pests can be controlled through weed control, birds, baits, and chemicals.
- Beet Armyworm - Beet armyworm causes the most damage to summer and fall-planted strawberries in southern California. They are foliage feeders, skeletonizing upper or lower leaf surfaces, attacking crowns of young plants, and killing them. They can be controlled through weed control, the Hyposoter exiguae parasite, natural viruses, and chemicals.
- Whiteflies - Whiteflies rarely build up to damaging numbers, but occasionally do during the late season. They have become more widespread in the last few years, especially the greenhouse whitefly. They suck plant juices and can excrete large amounts of honeydew on which sooty mold grows. These pests can be managed through topping, dust reduction, vacuuming, parasites and predators, and chemicals.
- Botrytis Fruit Rot - This is the most common and serious disease for strawberries in California. It can affect all parts of the plant, impacting both fruit and nursery production. It can reduce value of harvest by 30-40%, or as much as 50-60% when severe disease occurs, leading to an economic loss up to 100%. Infected berries maintain shape and take on a velvety grey brown coat. Areas rot, berries are infected, and damage in nurseries is significant. It can be controlled through removal of infected material, altering canopy size, barriers/mulches, less fertilizers, and chemical application.
- Verticillium Wilt - Verticillium wilt is becoming increasingly important in CA strawberries. It’s slow-growing but difficult to eradicate. It is a soil-borne fungus, and loss of methyl bromid/chloropicrin combo is expected to have a significant adverse effect on this disease’s eradication. It causes outer leaves to exhibit marginal browning and eventual collapse. It can be managed through fertilizer limitation, crop rotation, irrigation control, field selection, resistant cultivars, and chemicals.
- Rhizopus Fruit Rot - This fungus thrives on decaying organic matter, aiding its decomposition. It enters strawberries through wounds, releasing enzymes that degrade tissue, leading to a white mycelium and spore coat in high humidity. High temperatures worsen the issue, causing significant damage. This disease has led to 20-35% production loss. It can be managed through sanitation, post-harvest cooling, varietal effects, and chemicals.
- Powdery Mildew - Powdery mildew primarily affects coastal and northern nurseries, causing minimal damage inland. Infected flowers yield deformed or no fruit. Severe cases result in mycelium-covered and killed flowers. Infected young fruits become desiccated, leading to "bronzing." Leaves show small white powdery colonies initially on their undersides. It can be managed through resistant cultivars, overhead irrigation, biofungicides such as Ampelomyces quisqualis, and chemicals.
- Phytophthora Crown Rot & Root Rot - Phytophthora, a soil-borne fungal genus, often leads to stunting. Young strawberry leaves wilt, turn bluish-green. Plant collapse varies based on Phytophthora species. Infected plants display brown crown tissue. Root tissue also affected, causing brown to black rot. It can be controlled through low moisture, resistance/prevention, specific varieties, and chemicals.
- Common Leaf Spot - Common leaf spot is the primary strawberry leaf disease in California. While its significance has decreased, it can devastate fields if not controlled. The pathogen enters fields via black sclerotia on nursery plants, germinating with autumn rains. Wind-driven rain disperses its spores. It affects all nursery and fruit areas, but is rarer in drier inland valleys and the south. It can be controlled through drip irrigation, leaf removal, clean stock, and chemicals.
- Anthracnose - Anthracnose impacts flowers and both ripe and unripe fruit. Favorable conditions for its development include warm or cool and wet weather, which lead to fruit and stem rot. Additionally, Anthracnose can induce root and crown rot, with the most severe issues arising in nursery stock. It can be controlled through planting stock, removal of soil, and chemicals.
Further Resources:
Considerations for Climate Change Impacts on Strawberry Production
Climate change and weather are having a significant impact on strawberry production both domestically and globally, though the exact nature of these impacts in any specific region are difficult to accurately predict.
- Shifts in Growing Seasons and Regions - changing patterns of heat and precipitation is likely to cause shifts in both growing seasons and growing regions for strawberries. Especially in Florida, current models predict that many parts of Florida will no longer be well-suited for producing the fall/winter strawberry crop that has become their niche, and growers could likewise experience significant decreasing yields (and related lost income) as a result of shifting mean temperatures. Similarly, increasingly unpredictable cold snaps and frosts during flowering and fruit can do significant damage to strawberry crops.
- Heat Stress - Heatwaves and higher temperatures associated with climate change can have significant detrimental impacts on strawberry yields, due to the fact that many strawberry varieties only bloom and fruit when temperatures remain below approximately 75 degrees Fahrenheit. Growers may need to implement strategies, including indoor or greenhouse production, to mitigate heat stress risks.
- Water Availability - Climate change can influence water availability, with some regions experiencing more frequent and severe droughts or changes in precipitation patterns. Water scarcity can impact strawberry production, particularly if irrigation supplies become limited. Improved water management practices, such as efficient irrigation systems and water conservation measures, may become even more critical. Additionally excess water can also be a problem for strawberry producers, because fruit are highly sensitive to temperature and humidity damage and sit close to the ground. Therefore flooding, even for a short period of time, can be devastating to a strawberry crop.
- Pest and Disease - Climate change can influence the distribution and abundance of pests and diseases that affect strawberries. Changes in temperature and humidity levels can impact the prevalence and geographic range of pests and diseases, potentially leading to new or increased pest pressure. Growers may need to adapt their pest management strategies and be vigilant for emerging threats.
Learn more about the Effects of Climate Change on Strawberry Production.
Additional Resources
- Darrow - Strawberry Book (pdf, ~400 pages)
- “Strawberry production in forced and protected culture in Europe as a response to climate change”
- Cal Poly Strawberry Center website
- Our work: many publications posted here
- Cal Poly Strawberry Center Youtube
- Lecture Series on Current Issues in the Strawberry Industry