Most commercial greenhouses are growing vegetables on vertical high-wires these days, and the demand for artificial lighting has been increasing for years. To help greenhouse growers grow their crops even more efficiently, Philips lighting is always searching for the most effective solution. Ten years ago, we introduced a new type of lighting called interlighting, followed recently by a high-output version. By now, this way of applying light to plants has proved itself numerous times, and we’d like to share what we’ve learned along the way.
Many high-wire crops like cucumbers and tomatoes are grown using traditional HPS (high pressure sodium) grow lights above the crop. But with the arrival of LED interlighting in 2008, Philips lighting began researching the effects of placing LED lighting within the canopy of high-wire plants to improve crop yield and quality. These trials showed that placing LED interlighting within the canopy of high-wire plants allows you to focus growth-stimulating light on parts of the crop that are normally darker, so that the leaves have an even greater impact on fruit production. This can significantly improve the quality and yields of crops.
Back in 2010, Dutch tomato grower Jami and his growers' cooperative were closely involved in these trials, and the positive results convinced them that intercanopy lighting was the way to go. In 2012, growers cooperative Van Nature (where Jami is one of the members) invested in a Philips hybrid lighting system, combining HPS lights with a double line of LED interlighting which was installed in Jami's greenhouse. Their greenhouse was too low to accommodate sufficient HPS lighting to support year-round production. That meant that this hybrid lighting solution was the best option for them. At that time, it was a 'forced choice'. Ask them now, and based on their experience and results with LED, they wouldn't want anything else.