The automated vertical agriculture sector is thriving as more and more different crops are grown in vertical farms. Once, it started with herbs and leafy vegetables, but now the focus is on vertical cultivation of strawberries. Rudy van den Berg, Commercial Manager at Artechno Growsystems, talks all about the possibilities of growing strawberries in a vertical farm.
Why is there so much interest in growing strawberries in a vertical farm?
"Strawberry cultivation is fragile, so it is beneficial to grow strawberries as close to the consumer as possible. One will have less product loss by minimizing handling and transportation time between harvest and the point of sale. That makes vertical farming of strawberries immensely interesting."
Do strawberries grow well in a vertical farm?
"Yes. The strawberry plant is similar in height to leafy vegetables and, thus, very suitable for vertical farming. In automated vertical strawberry farms, they can be grown in vertically stacked layers. It is different with raspberries because they grow higher, making it difficult to grow them in vertical layers."
So why aren't strawberries grown vertically by default?
"To grow strawberries profitably, you have to consider the many aspects of a vertical farm. The route a strawberry plant takes through a vertical farm, and the crop treatments it requires is completely different from the route of, say, lettuce."
But it's not impossible?
"No, definitely not. In fact, we have done a trial in our Research Center with strawberries. The conclusion from this trial is that we can grow strawberry plants with our AVF+ technology. So that is very positive. But there are still challenges that we want to solve before we start offering this technology to our customers."
What are the challenges of vertical farming for strawberries?
"There are seven challenges, or perhaps 'issues' is a more appropriate term, that we are currently deciding on and exploring further at Artechno Growsystems."
Challenge 1: cultivation recipes.
"We need to develop and optimize growing recipes for strawberry plants. This means, for example, researching the optimal light and CO₂ levels for these plants.
Some competitors and companies have already done research on this. However, that knowledge is not fully disclosed, nor is it always applicable to our AVF+ technology. We are, therefore, starting from scratch and developing the best cultivation recipes in our Research Center, which requires the necessary time investment."
Challenge 2: Multiple harvests
"Strawberry plants produce multiple harvests. By comparison, when we grow a head of lettuce, the plant comes up once, is harvested, and then goes to the packing line, for example. After that, new seeds must be planted to grow fresh lettuce. With a strawberry plant, you pick the strawberries, and after harvesting, the plant has to be brought back into the vertical farm to continue growing."
On the way to the plant
"The principle of our AVF+ technology is that the plant moves toward the human or processing line. To make that possible, we use benches and trays to transport the crops.
In vertical strawberry farms, humans have to go to the strawberry plant to pick the strawberries. We will have to develop a solution for that because our current methodology works exactly the other way around. In other words, we have to figure out how the strawberry plant will move through the automated vertical plant."
Challenge 3: Two types of strawberry plants
"We are dealing with two different types of strawberry plants:
- June bearers
Produce a lot of strawberries in a short period of time, but none in the winter.
Produce fewer strawberries but over a longer period of time.
Both types of strawberry plants require completely different cultivation processes. So, we have to choose which plant type to develop a system for. You can't put the different varieties together and choose a mix."
Little time, lots of strawberries
"At Artechno Growsystems, we chose June-bearers because this type produces a lot of strawberries in a short time. A June bearer needs a certain number of cold hours before the plant starts producing strawberries again. The actions in this process include the following:
- You must remove the plant from the cold and carefully prepare it for cultivation in the AVF+ Compact.
- The plant enters the automated vertical farm (AVF+), where the crop is balanced with all environmental factors, such as climate, nutrition, irrigation, light intensity period, and spectrum.
- Once the clusters have sprouted far enough, the plants are prepared for their "flowering" and "harvesting" phase.
- The pollinated flowers produce strawberries and are removed from the farm when they are at their ripest.
- After the flowering and harvesting phase, the plants are again prepared for cold treatment before a new growth cycle begins.
A perennial plant does not need to be placed in a cold environment but should be picked regularly. Multiple cycles, i.e., crop changes, per year are essential to achieve high production. Therefore, for indoor strawberry cultivation, a good supply of plant material is important."
Challenge 4: Crop treatment
"Unlike crops such as leafy vegetables and herbs, strawberry plants require crop treatment, including leaf removal. Crop maintenance must be performed outside the AVF+ Compact. So even for this, the plant has to be taken out of the vertical farm several times. Of course, we are going to automate all that because this will make the automated vertical farm much more efficient."
Challenge 5: Water the plants
"When you talk about water release, you see we use hydroponics in our AVF+ plants. That means we use ebb and flow or a constant layer of water in the bank. Strawberry plants are typically watered with drip irrigation rather than constant water release. This uses a drip system, similar to tomato plants. The system doses into each pot the amount of water a plant needs. We are currently developing the technology to implement this in our AVF+ Compact."
Challenge 6: Optimal quality
"For a profitable product, you want to grow high-quality strawberries that retain their quality even after harvest. The product should be at least as good, preferably better, as strawberries from the greenhouse or in the open field.
By quality, you can think of:
- Shelf life
In an automated vertical strawberry nursery with a controlled environment, we can create the perfect climate to guarantee a high-quality and delicious strawberry. By adding the right nutrients, the flavor can be influenced."
Challenge 7: Cuttings
"Around the world, you see that the best strawberry varieties are propagated vegetatively. In short, this means that a part of a plant is taken, which is then placed in a root environment, and a new plant is eventually produced from that. This means importing plant material into the culture cell. In automated vertical farms, you prefer to avoid that. If you import plant material, you run the risk of bringing in plant diseases, insects, pests, and even viruses."
"For high-quality, uniform, and clean starting material, cutting production is organized in-house. To guarantee that the plants are 100% free of pests and spores, the mother plants must be raised from tissue culture."
"The best solution for this is to work with tissue culture, the technology of sterile laboratory plants. Seeds can also be used, but this is not yet common among strawberry growers in greenhouses or outdoors. Seeds would be the best solution for the AVF+. Nevertheless, the available strawberry varieties still do not meet the highest quality standards in terms of taste, shape, and color."
Growing strawberries in an automated vertical plant presents challenges; is it still worth it?
"Definitely. There is a huge demand for it because it is such a problematic crop. However, developments like the Strawberry Vertical Farm require a lot of time, R&D, and engineering. At Artechno Growsystems, we have to make sure there is time and capacity available. We will then build a fantastic solution that offers numerous benefits."
What benefits do vertical strawberry farms offer?
"Some of the benefits of growing strawberries vertically indoors:
- You get the same constant yield of strawberries year-round and weekly and, therefore, an annual fixed selling price.
- You can deliver quality and taste at the highest level.
- You save space.
- Everything is automated, as opposed to labor-intensive farming.
- 100% clean and pesticide-free strawberries.
- Future-proof growing.
- Juicy strawberries are grown close to the consumer.
Because of the above, you can eventually turn strawberries into a stable, profitable product."
What about that profitability now?
"We are aiming for strawberry production of 40 kilograms per square meter per year, with consistent Class I quality. However, more research is needed to achieve that goal. The next step is to make the product widely available to the consumer market. In other words, providing a basic, high-quality product. In terms of price level, you have to be in line with the price of strawberries from the greenhouse; otherwise, consumers will just walk right past you. If you look at the Dutch market, we have to aim for 60 kilos per m2 to achieve that goal."
How are strawberry developments going at Artechno Growsystems?
"We are well on our way. After a few months, we have completed a long-term trial. The main points are developing the growing recipe, choosing the varieties of strawberry plants, logistics, and automation of the growing process. That sounds like a lot of work, and it is, but we are making rapid progress. Nevertheless, we will conduct a second trial this year, working toward a proof of concept."
"Don't get me wrong, by the way. Technically, we can develop a strawberry farm within a few weeks, but not with the quality standards we guarantee at Artechno. We want the solution we offer to work optimally so that our customers can definitely generate revenue. So we first want to have solved the biggest challenges and actually be able to grow strawberries sustainably before we bring a new technology to market."
How will that be solved?
"We are calling on plant breeders and genetics companies to further develop these types of crops and make them suitable for vertical farming. There are already some initiatives in this area, such as dwarf tomato plants. However, the supply is scarce, and the quality does not yet match the quality of traditional tomato plants. But if they develop that, it will become possible to grow this kind of multilayer crop. Once that happens, we will take huge and essential steps forward in automated vertical farming."
Strawberries are a fragile product. So, it is advantageous to grow strawberries close to the consumer. Strawberry plants are suitable for automated vertical farming. However, some challenges remain to be overcome, including developing a growing recipe. Vertically grown strawberries offer numerous advantages, including the year-round delivery of top-quality, pesticide-free strawberries. Artechno Growsystems is developing a profitable solution for automated vertical growing of strawberries and will bring that solution to market within three years.