A recent Horti Daily article discussed the problems with limited venting experienced by many greenhouses in the Leamington, Ontario area. Venting limits are imposed by local municipalities to address light pollution concerns. Venting is a strategy used by greenhouses to remove warm air from the greenhouse as temperatures rise, especially in the warmer months. Venting limits make it difficult for greenhouses to remove warm air and maintain optimal temperatures in greenhouses. An unintended consequence with artificial lights is that opening greenhouse side walls and roofs allows light escaping, causing light pollution to the neighboring area outside.

Greenhouse growers are constantly juggling and adjusting growth parameters like light, temperature, and CO2 to create an optimal growth environment for their plants. Choosing to vent or not is always a double-edged sword. On the one hand, venting is an inexpensive way to manage air exchange in order to keep temperatures cooler in the warm months from spring through fall. On the other hand, venting with artificial lights on results in light pollution. Venting also makes it impractical to supplement the greenhouse grow area with CO2 by atmospheric enrichment (also known as CO2 gassing) since the CO2 gas quickly escapes outside.

The problem with venting is not usually an issue for Leamington greenhouses in the colder months when the vents are closed, thereby enabling CO2 gassing as the facility is sealed and reduces artificial light pollution. CO2 gas levels in the grow rooms can be maintained at 1200 parts per million (ppm) to optimize growth. However, in the warmer months when venting occurs, it is very difficult to maintain 400 ppm (the level of natural CO2 in the air) even if CO2 gas is pumped into the grow area since nearly all of it escapes outside during venting.

CO2 Delivery Solutions™ can help Leamington greenhouse growers solve the CO2 supplementing problem when venting.

CO2 Delivery Solutions™ enables Leamington greenhouses to provide their plants with added CO2 which enhances growth and yields. This capability is achieved by misting an aqueous CO2 solution directly on to the plants, with or without venting. This technology allows CO2 to be controlled independently, rather than its delivery being co-dependent on the control of other growth parameters like light and temperature. This enhances a grower’s ability to optimize environments in a simpler and more effective manner. While CO2 Delivery Solutions™ cannot solve the artificial light pollution problem when Leamington greenhouses need to vent, it can certainly solve the lack of optimal CO2 problem during those months and help tip the balance towards more optimal yields year-round.

Visit co2delivery.ca for more information.