Mauricio Manotas
Photo courtesy of Ludvig Svensson

Shade curtains are a key part of many greenhouse operations. But growers have to make sure shade curtains are optimized for their facilities and being used correctly. Below, Ludvig Svensson president Mauricio Manotas offers his insight on how to use shade curtains in the fall, how to pick one with the right opacity and more.

Greenhouse Management: How should growers adjust their shade curtain use as they shift into fall production and are dealing with lower light levels?

Mauricio Manotas: Natural light levels will start to drop in the coming weeks, and the shade curtains’ setup needs to be modified accordingly. We strongly recommend growers connect the curtain to a light reader on the greenhouse and have clear set limits on when it needs to be open and closed. That will depend on the greenhouse location and crop. Most climate control stations (Wadsworth, MicroGrow, Priva, Hoogendoorn) have settings depending on the seasons and will be able to operate the curtains based on that. If a grower doesn’t have that type of controller, we recommend that in any case they keep the curtains closed (extended) at all times during the night which is where most of the heat is lost on a greenhouse.

GM: How can growers select the right shade curtain opacity for their operation?

MM: The right curtain will depend 100 percent on the crop and the location. It’s a completely different environment if you’re growing mums or peppers in Florida than if you are in New Jersey. The greenhouse builders and curtain manufacturers should be able to recommend the right product after having a conversation with the grower. It’s important to know the location, the crop, the strategy and the greenhouse type to make sure growers are getting the right product. There is definitely not a solution that works for everybody everywhere.

GM: What are some common mistakes growers make with shade curtains?

MM: First and foremost, you want to make sure you got the right product for your area and for your crop. An energy conservation curtain that is a must in Canada will probably bring only headaches and disappointment in Georgia. I see sometimes folks overshading, sending the plants into a more vegetative state [and] limiting fruits and flowers. This normally happens when they react a little late to pull the shades to lower the temperature. But the most common mistake we see is the lack of seals when using energy conservation curtains. Every gap and hole that we see will be an opening for the heating being applied to escape the greenhouse. The efficiency of an energy curtain will drop dramatically when we don’t take care of that.

GM: For holiday crop production, what are some best practices for shade curtains?

MM: Mums and poinsettias season is around the corner. It is time to check the mechanical systems and curtains to make sure any possible repair is done on time and not during the middle of the season. Timing the crop right is the main success factor for the holiday crop. Let’s make sure seals are checked, wires are replaced, motors are working to have a successful season.