How FR Lights Can Influence Strawberry

Especially since the effect of far-red light on strawberries is not very well-documented yet, there are some data on its effect on tomatoes, but strawberries are a completely different crop. For example, in strawberries, you have short-day varieties – they need short days and long nights to initiate flowers and grow best – whereas tomatoes are day-neutral; they need about 6 hours of darkness, but theoretically they can be lit the rest of the time. Furthermore, strawberries, especially the Junebearers, have one flush, and then it’s over, but you can harvest tomatoes year-round as they have a constant plant load. Because the crops are so different, they also have different needs when it comes to light.”

A research report proved that FR red has good effect on strawberry. For example, that plants were more open because of the far-red light. This is beneficial not only because the plant can intercept more light in that way, but also because air ventilation in the crop becomes more effective. On top of that, labor becomes easier as well, as fruits are easier to reach and pick because of the truss elongation caused by far-red. We also saw positive effects in yields, and Brix values were higher, too.

With the current energy crisis, sustainability and energy efficiency are critical to consider for lit cultivation. However, Leo and Haris are convinced LED is the best way to go. “When you look at lit strawberry crops, most of it is under HPS. However, because of the higher efficiency and efficacy of LED lighting, we expect that a switch from HPS to LED might go fast, especially with the energy crisis. Investments in lighting and research are not just for the short term – they are for the next 5+ years. Such a switch might be a big investment, but it will massively save costs in the end,” Haris states.

Leo agrees that LED is the most viable option for lit strawberry cultivation, especially as strawberries prefer lower temperatures and because we expect to move toward higher light intensities in coming years. “If growers using HPS will increase light intensity, temperatures in the greenhouse will also rise. As strawberries are not the biggest fan of higher temperatures, you will not win much by increasing light intensity under HPS. With LED, however, increasing light intensity does not equal increasing temperature – or, well, that increase is so small that it can easily be managed – making it much better suited for lit strawberry cultivation.”