Le Jardin de Rabelais is a tomato nursery established in 1989 in the heart of the Loire Valley, France. Owner Pascal Delahaye is from a real horticultural family. This true-blooded Frenchman gained his knowledge about substrate cultivation abroad and then returned to his native soil to set up his own nursery. His nephew Matthieu Serrault also joined the company 5 years ago.
Le Jardin de Rabelais has two production sites. The site in Savigny consists of a traditional Venlo greenhouse (3 ha) and a SuprimAir greenhouse (3 ha) that was built in 2012. The site in Avoine features a traditional Venlo greenhouse (5.5 ha, including 1.6 ha with LED lighting). The most recent greenhouse is suitable for The New Cultivation (TNC), with poly tubes underneath the growing gutters and fresh air intake.
The challenge
Le Jardin de Rabelais deliberately targets the higher-end segment of the market. Both fine vine tomatoes and cherry tomatoes are grown at the nursery. Delahaye decided on the Piccolo variety, which has a superb taste but is not easy to grow. A great deal of attention is paid to the quality of the fruits and to packaging, which is geared to the customer.
For the past few years the grower has had an HPS lighting installation with a capacity of 125 μmol/m2.s for the purpose of extending the growing season. Delahaye says: “We don’t need more tomatoes in summer, but we do in winter. For us, artificial lighting is a step on the path towards year-round uniform production.” The grower opted for the latest development in artificial lighting: LED interlighting. He went to the Netherlands to find out about research results and the initial practical results obtained by his Dutch colleagues.
The solution
“We lowered the existing HPS only because they were too high (at the level of the trellis), to make it possible to install a screen,” says Pascal Delahaye. “The light intensity is still 125 μmol/m2.s. We had to change to wider reflectors because the distance between the crop and the lamp is now smaller, because the lamps are below the trellis. The interlighting in two strands has a total intensity of 110 μmol/m2.s. This means that the total capacity is now 235 μmol/m2.s. Together the lighting systems provide a plant reaction that is equivalent to 285 μmol/m2.s, a huge leap forward”.
Remarkably, the installer performed the entire operation in a greenhouse covering an area of 16,000 m2 that still had crops growing in it. This is because the production site changes crops once a year, with intermediary crops being planted in September. “In fact we never have a break from producing, since we want to serve the market all year round,” explains Delahaye. The LED interlighting system can be hoisted. This mechanism was thought up by Certhon and it means that the interlighting can ‘grow along’ with the crop. The hoisting is done by hand.
Benefits
“Here we have a different climate from the Netherlands. It is always a couple of degrees warmer in both summer and winter. We needed a more heavy-duty lighting installation, but definitely didn’t want the plant temperature to increase by too much,” explains Delahaye. “This is why I was interested in LED lamps, which produce far less heat than HPS lighting. Fitting the system was a lot of work, but we were able to do it using mostly our own staff.”
The grower opted for two strands because this meant that he had better light distribution with plenty of light between the plants. He was able to use the full lighting for the first time in the winter of 2014/15, another step towards achieving uniform year-round production.
For more information
Philips horticulture LED Solutions