Pura Hoja is Chile’s biggest lettuce grower, producing 15 million hydroponic lettuces per year in Quillota in the Valparaíso region. According to Production Manager Sebastián Pacheco, Grodan’s stone wool growing media have played a key role in the company’s production processes for over 15 years. “Grodan’s stone wool was easy to integrate into our automated hydroponic systems. Thanks to greater control over irrigation and nutrient delivery, combined with Grodan’s advice and guidance, we achieve uniform crops with stable performance for the duration of the cultivation cycle. Grodan is an essential part of our living lettuce production,” he says.
Pura Hoja was founded in 2009 to meet Chilean retailers’ demands for a reliable year-round supply by growing lettuce hydroponically on gutters. “We went in search of a suitable substrate that would integrate seamlessly with our newly installed, automated mobile gulley system (MGS) from Hortiplan, while also providing reliability in lettuce production. Key factors for us were uniformity, healthy growth and effective water retention management in relation to irrigation,” explains Sebastián.
“I reached out to Grodan because I had previously worked very satisfactorily with their products for tomatoes and peppers at my former employer, Tomaval. But hydroponic lettuce was completely new for both of us in the beginning. Right from the start, the Grodan team showed a willingness to experiment and learn what works together. They even adapted their products to fit our operational conditions, enabling us to conduct trials with two different substrate sizes: 5x5x5 cm and 4x4x4 cm,” continues Sebastián. “Both block sizes delivered good results, but the larger one proved superior in terms of kg/m² yield. Once Grodan had fine-tuned the recipe for us, the uniformity and consistency of the substrate meant that it worked well every time.”
Innovation and automation
Pura Hoja started commercial lettuce production on Grodan’s MM blocks 5x5x5 cm in 2010, initially with 1.7 ha of production space and manual seeding. Over the years, the leading horticulture company has increasingly automated its processes – from irrigation and climate control to nursery management and daily operations. “Innovation is at the core of our company. Technological solutions are key in helping us improve both productivity and sustainability,” states Sebastián.
“Today, we have 7 ha, including 4.7 ha of high-tech greenhouse space for hydroponic lettuce production, a nursery where the lettuces are seeded automatically into the blocks, plus an NFT system for special lettuces and herbs, where we also use Grodan’s products,” he adds.
“Thanks to its homogeneous structure and consistency, Grodan’s stone wool has been easy to integrate with our trays, gutters and automated greenhouse irrigation system. This compatibility has enabled us to optimise water and nutrient use while significantly reducing operational time.”
In fact, the closed-loop irrigation system reduces water consumption by approximately 90% compared to open-field lettuce production. This is particularly important in Chile, where the availability of water is becoming a growing issue. “Hydroponic cultivation supports our sustainability goals in other ways too, such as by preventing the discharge of fertilisers into the soil, and avoiding soil erosion,” continues Sebastián.
More controllable and stable for the entire cycle
Because stone wool fibres are made from a mineral called basalt and heated to extremely high temperatures during production, stone wool growing media have no cation exchange capacity (CEC). “Compared to organic substrates, stone wool gives us greater control over irrigation and nutrient delivery, enabling us to maintain optimal levels of saturation and oxygenation for healthy root development. Supported by research and advice from Grodan on root zone conditions such as EC, pH and WC% as well as irrigation frequencies, we’re able to produce uniform crops with stable performance for the duration of the cultivation cycle,” comments the production manager. “Additionally, thanks to consistently excellent leaf quality, we reach the desired harvest weight faster and more efficiently.”
As a result, Pura Hoja currently achieves an average annual yield of around 100 kg/m2, amounting to approximately 15 million hydroponic lettuces per year. This enables the company to meet 90% of domestic demand, making it by far the biggest lettuce supplier in the country.
Hygiene matters
Besides the advantages from a production standpoint, stone wool offers Pura Hoja a number of operational benefits, according to Sebastián. “It has simplified our labour processes thanks to the ease of handling during both planting and harvesting. Moreover, by providing a ‘clean start’ with minimal risk of pests or pathogens originating from the substrate, it plays a key role in maintaining strict sanitary conditions in line with our safety protocols. In fact, it has even helped raise our hygiene standards, because the blocks minimise the buildup of organic matter that could harbour potentially harmful fungi and bacteria in our recirculating irrigation systems.”
For this producer of ‘living lettuces’, which are sold with the roots intact, hygiene and sanitary controls are the top priority. He explains: “Our business model revolves around customer satisfaction. Our clients value a product that is fresh, safe and visually appealing. Grodan’s stone wool blocks allow us to produce vibrant lettuces with consistently clean leaves and with nice, white roots that have no soil residue on them. This not only ensures product safety and consumer appreciation, but also contributes to up to a 30% longer post-harvest shelf life compared to other lettuces of the same size.”
Collaborative spirit
“The MM block 5x5x5 cm is the perfect solution for us in terms of the volume of the block and the size of the lettuce we can produce,” says Sebastián, when asked why he chooses to work with Grodan. “But the relationship with our suppliers goes far beyond the product itself; we build long-term relationships with those who share our vision and values as a company.”
“Having technological partners who truly understand our business and are committed to continuous evolution is essential for us, because we’re constantly seeking ways to enhance the efficiency, quality and environmental impact of our processes,” he continues. “Grodan has been an important part of this journey – not only as our main substrate supplier, but also by providing consistent technical and technological support, effective solutions and valuable guidance to help us achieve the best possible results.”
“This level of support – always delivered with professionalism and a collaborative spirit – has fostered trust and formed a strong foundation for our long-standing business relationship,” states the production manager.
Exploring new possibilities
“Today, Grodan is an essential part of our living lettuce production, and we are loyal to stone wool and to Grodan. In fact, we recommend it to the companies who grow lettuces on our behalf and advise them on how to use it – because stone wool requires a different approach to crop management. But once you’ve learned how to work with it, we believe it’s the best option for hydroponic methods.”
“In fact, we envision a future of even closer collaboration with Grodan – not only because we plan to expand by adding a new greenhouse in the next couple of years, but also because we continue to explore new possibilities to innovate with stone wool substrates. For example, we are currently running a production trial that has the potential to significantly boost our winter yields. If that is a success, I will be asking Grodan to develop another block tailored to our needs – and I’m sure they will be willing to share their knowledge, test and learn together with us again,” concludes Sebastián.
