Overview of the UK strawberry industry
State of the nation – overview of the UK’s strawberry industry
Soft fruit production in the UK has long been dominated by strawberries, blackcurrants and raspberries, which account for a large proportion of cropping area. The remainder includes blueberries and blackberries both of which continue to gain in popularity. Of the land used for growing soft fruit, a significant amount is home to polytunnels. This method increases the probability of a good crop and extends the UK growing season from 4-6 weeks to a much wider time frame of early spring to autumn. The remainder is grown under glass or uncovered.
Over the past 25 years the soft fruit production has grown by 600% in the UK. In 1996 the UK consumption stood at 67,000 tonnes of strawberries. By 2015, strawberry consumption had risen to 168,000 tonnes (up 150%). Reflecting this exponential increase, the production of soft fruit in the UK has developed significantly, now valued at over £1.5billion.
The cost of labour for British strawberry growers
Labour costs typically account for 50% of the cost of production for growers. The majority of labour for both the growing and harvesting of these crops in the UK is employed on a seasonal basis, with the greatest need from May to September, when many workers typically work for a 20-25 week season during this period.
Only a tiny fraction of this seasonal labour has historically been provided by British nationals, with the majority of workers coming from the European Union. This is because, in the past, agricultural wages were higher in the UK than in Europe, and in particular Eastern Europe.
However, with the impact of Brexit on the freedom of movement, coupled with the travel restrictions caused by Covid, those who have formed most of the strawberry pickers in recent years have understandably turned their backs on British farms. Consequently, huge pressure has been placed on fruit farmers as they struggle to harvest their produce and meet the growing demand for soft fruit.
British strawberry growers look to increase productivity through innovation
Growers’ costs are increasing through inflation, transportation, utility price-hikes and other aspects of the food supply chain (see our blog here regarding these factors). However, until recently the product value of strawberries, and the price, has remained relatively static for around 15 years. Producers are being forced to look at other ways to boost productivity and therefore to lower their labour requirements per tonne of production.
Polytunnels have made huge differences to production in the last ten years or more, because not only do they protect the fruit from the vagaries of the British climate, but they also provide the means by which growers can adjust harvest timings and extend the availability of UK grown crops.
One of the most important advances in productivity is the continuing conversion of strawberry production from soil to substrate grown crops, such as peat, which provide a consistent and soil-borne disease-free environment and have a lower labour requirement.
However, in response to historic consumer pressure and government policy about peat usage, the horticulture industry has invested heavily in finding ways to grow crops more sustainably in peat substitutes such as coir, bark, green compost and wood fibre.
One innovation to keep an eye on is that of vertical growing. The environmental benefits of this are being analysed and the feasibility studies conducted. If challenges regarding yield can be addressed, this could be an exciting new chapter for strawberry growing – the way up rather simply than the way forward!
Can robots replace humans in strawberry picking?
Robotic harvesting of strawberries is now in development as growers attempt to minimise the effects of labour shortages. Recent advances in visual sensor technology, machine learning and autonomous propulsion have brought the goals within reach.
A commercial strawberry picking robot was launched at Fruit Logistica in February 2019. The Belgian manufacturer, Octinion, claims the Rubion is the first commercial strawberry picking robot and can harvest around 1 fruit every 5 seconds. They argue they are achieving fast picking speeds by building the robot to replicate how people pick strawberries – by touching and snapping the fruit from the stem, not cutting it. The robot has been designed from scratch, which they believe makes their product very cost effective, and should be available to growers from January 2020.
However, this robotic picker is only suitable for strawberries grown in substrate on table-top systems. Other manufacturers are taking a different approach. Cambridge-based company Dogtooth, for example, created a picker based around robotic arms mounted on a mobile platform. The main difference between these 2 innovative products is that Dogtooth’s machine will pick traditional British varieties in the field.
A three-year PHD studentship project at Lincoln University is working to develop the vision systems required by a robot to decide which strawberries are ready to pick. The work takes inspiration from insects such as bees and fruit flies, which use visual cues invisible to humans and which tend to be overlooked by engineers. Students used a specially developed camera to collect a novel image database of fruits and flowers at various stages of development and in different weather, lighting and protected conditions. Analysis of the results provides a vision system to drive a robotic strawberry harvester.
Robotic picking will, however, only potentially partially address seasonal labour costs and doesn’t help growers with the rising costs regarding crop establishment, husbandry, management of coverings, transportation, fuel and grading/packing.
Strawberry crops need effective pest control
Crop protection is key to improving crop yield and productivity. The Agriculture and Horticulture Development Board (AHDB) has long been working with the British soft fruit industry to deliver new pest and disease control in strawberry production. Their priorities included spotted wing drosophila, western flower thrips and strawberry powdery mildew.
Spotted wing drosophila (SWD) first appeared in the UK in August 2012. It is one of the most serious pests of thin-skinned fruits such as strawberries. Drosophila suzukii presents a real challenge to the UK soft fruit industry, as containment or eradication of this pest has so far proved difficult.
Amongst a number of AHDB-funded projects, a four-year PHD project at the University of Greenwich investigated control methods for SWD. The research aimed to optimise attractants and repellents and their deployment. Improved understanding of the insects’ sense of smell and searching behaviour helps to provide the basis for the development of a push/pull system.
Innovations in strawberry varieties
Until recently, the most popular strawberry in the UK was a Dutch variety called Elsanta. Resistant to disease and giving high, consistent yields, the breed was popular with growers. However, a belief amongst many consumers that Elsanta was rather bland led to growers and retailers looking for a suitable alternative.
According to Sainsbury’s category technical manager for fruit, Maddie Wilson a few years ago “The holy grail is finding something that is a grower’s dream: easy to plant, yields well, performs well in different weather and gets the right size of fruit, the plants last a long time, taste delicious and look lovely”. This still holds true, today.
Introduced in 2013, Malling Centenary was developed at the East Malling Breeding Club, based at NIAB EMR in Kent. It was very much in demand owing to its very high percentage of Class I fruit and reduced picking costs. It also scored highly in consumer taste trials with a richer, deeper flavour when compared with Elsanta.
Following the success of Malling Centenary, AHDB continued to part-fund the East Malling Strawberry Breeding Club to develop improved strawberry varieties, both June-bearing and everbearing, with increased yield, larger fruit size, an extended production season and greater resistance to fungal diseases.
The June bearer is Malling Allure, a late Malling Centenary-type berry which has a similar season to Florence but with better fruit size, appearance and plant habit. The everbearer is Malling Champion, which as an early season production with a Class 1 yield and large fruit size. Initial assessments show resistance to key diseases such as crown rot. Both of these varieties were available from 2019.
The future of strawberries
It takes about seven years to go from a promising seedling to a commercial variety. Research projects on pest control tend to take between three and four years. Growers cannot expect overnight success with innovation. They can, however, expect that the industry as a whole continues to face up to its challenges to ensure a consistent supply of delicious, disease-free and sustainably-grown strawberries to British consumers. What the future holds with regards to the feasibility, sustainability and yield of innovations such as vertical strawberry growing remains to be seen.