French cucumber growers tune LEDs for year-round production

Two greenhouses are the latest to tap lights from Signify with brightness levels and frequencies optimized for the vegetable

In another horticultural example of how LEDs can be finely tuned to suit different crops, Signify said that two French cucumber farms have installed greenhouse solid-state lighting (SSL) systems that optimize year-round growth of the popular salad vegetable.

Jardins Réunis and Cheminant, both close to the city of Nantes near the northwest coast, have deployed Signify’s Philips GreenPower LEDs set with a recipe that delivers brightness and frequency levels believed to be ideal for cucumbers. The passively cooled SSL also steers heat away from the crop, which likes temperatures from around 75° to 80°F.

Neither Signify nor the growers would reveal the specific plant recipe.

Both Jardins Réunis and Cheminant grow “high-wire” cucumbers, a technique in which the cucumber vine climbs vertically and then runs horizontally along a wire. Both are using top-lighting above the plants and inter-lighting within them.

“LED lighting will help us to improve energy efficiency and to reduce gaps in production, especially in the more profitable winter period,” said Vincent Olivon, co-owner of Jardins Réunis, which has installed the lights across a 25,000m² (269,000-ft²) greenhouse. “This is critical in sustaining our position in the market year-round.”

Cheminant’s installation is a similar size, at 20,000m² (215,000 ft²).

“LEDs give a better heat-light balance, generating a significant increase in production without the heat that you would get with high-pressure sodium lighting,” said Cheminant co-owner Antoine Cheminant, “As per Signify’s calculations, we’re aiming for 30% more production in our 20,000 m² semi-closed lit greenhouse compared to a traditional non-lit greenhouse."

These cucumber plants at Cheminant will reach for the lights. (Photo credit: Signify.)

Both companies installed the horticultural SSL in November 2018. Signify timed this week’s announcement to coincide with SIVAL, a French trade show in Angers focused on plant production.

Signify — formerly called Philips Lighting — has installed cucumber lighting systems in other countries, including Holland, Russia, Finland, Poland, Latvia, and Canada, among others.

It has also installed a number of Philips-branded lights tuned for tomatoes, such as at Russia-based Agro-Inwest.

MARK HALPER is a contributing editor for LEDs Magazine, and an energy, technology, and business journalist ([email protected]).