"Climate control is driven more by evolving plant requirements than by the external environment"
Source: VFD.com
Burleigh Dodds Science Publishing's Francis Dodds: "Climate control is driven more by evolving plant requirements than by the external environment" The way greenhouse climate control is managed has changed fundamentally over the past two decades, shifting from simple rules-based systems to approaches driven by real-time crop physiology. "And then obviously with developments in computing and other technologies, there's a move to more sophisticated integrated control which balances different variables." © Unsplash | Katrien Van crombrugghe The speaking plant concept The most significant development, according to Dodds, has been the emergence of sensors and models capable of monitoring crop physiology directly, an approach known as the speaking plant concept.
"There's been a move to proactive rather than reactive model predictive control systems," Dodds says, "which, for example, will incorporate weather forecasting data and energy pricing data." Temperature: heating and cooling On heating technologies, Dodds notes that the building envelope itself remains a primary tool, with double-layer greenhouse covers, thermal screens, and curtains. "It's now possible to develop more dynamic, flexible temperature management regimes which allow the air to fluctuate within pre-determined limits while maintaining a target mean over a given period," he says, "and that still optimises plant growth but can lead to energy savings." Tighter temperature management during reproductive growth phases and looser management during vegetative stages becomes a viable operational strategy.
Humidity: from set points to VPD On humidity technologies, Dodds maps a similar landscape across three areas: building-level measures such as double-layer roofing and anti-drip systems; active humidification via sprinklers, fogging, and misting; and active dehumidification through natural and forced ventilation, solid and liquid desiccants, hygroscopic materials, heat pumps, and heat exchangers. "VPD is a measure of actual versus potential moisture in the air, broadly speaking, its drying power," Dodds says, "and extremes in vapour pressure deficit conditions can substantially affect and damage plant growth in areas such as transpiration, photosynthesis, and stomatal opening." "There's been a movement from rigid relative humidity set points to more flexible minimum and maximum ranges, which balance the various challenges," he says.
Why this matters: For operators, this is a water-management story. The useful signal is that direct substrate measurements can help cut drain loss materially without giving up yield or fruit quality, which is exactly the kind of controllable efficiency gain a facility can build on.
Frequently Asked Questions
Why does substrate sensing matter in free-drain strawberry systems?
Because drain percentage tells a grower what already happened, while substrate moisture and EC data show root-zone conditions directly. That makes it easier to cut water loss without guessing.
What is the operator takeaway from this trial?
If the thresholds are understood well enough, growers can reduce drain water materially while protecting yield and fruit quality, which makes sensing an operational tool instead of a reporting tool.
