Vapor Pressure Deficit and Indoor Growing: Part 3: Different Stages of VPD

Written by Mike Steffes – Quest Dehumidifiers VPD Range Now that we’ve established the importance of transpiration and have some idea of how it happens, it should not be a stretch to accept that plant transpiration is driven by a vapor pressure difference of water: The partial pressure of water within the leaf vs. the […]

See full article


Vapor Pressure Deficit and Indoor Growing: Part 2: Why is VPD Important?

Written by Mike Steffes – Quest Dehumidifiers Why Vapor Pressure Deficit is Important Plants survive and grow using sunlight, carbon dioxide, and water plus a number of inorganic elements (N, P, K, Ca, Mg, etc.). Plant metabolism runs off of two major classes of reactions: Light dependent reactions- these use water and produce oxygen as […]

See full article


Vapor Pressure Deficit and Indoor Growing: Part 1: What is VPD?

Written by Mike Steffes – Quest Dehumidifiers Why is Vapor Pressure Deficit Important? VPD helps a grower identify healthy air moisture conditions over the full range of growing temperatures. Vapor pressure deficit correlates directly to plant transpiration rates. Using VPD to fine tune water flow through the plant gives the grower another “control knob” in […]

See full article


Basalt Mineral Wool: The Key to Perfect Irrigation in Your Grow Room

Commercial growers use basalt (or basaltic) mineral wool in their hydroponic growrooms, and you should consider using it, too. What is mineral wool? Also known as “stone wool,” mineral wool is manmade fiber spun out of rock. Although it can be spun out of a variety of rock types, mineral wool spun out of basaltic […]

See full article


Dissolved Oxygen for Better Growth: Part II: Effects of Root Oxygen Starvation, Methods of DO Production, and Effective Aeration and Nutrient Delivery

Plants grown in a hydroponic system need dissolved oxygen (DO) in their water to thrive and provide optimal yields; in hydroponic systems, most oxygen absorbed by plant roots comes from the nutrient solution you provide.   Going beneath the surface: The root system, or “rhizosphere”   Plants receive nutrition via two different conduits: The aerial […]

See full article