A really explosive week of growth. I pushed PPFD up to 310umols. Dimmers are at 60% which is drawing 224w plus 18w of DRRB. I have alos started Emerson effect ... Another The Emerson effect is triggered by the simultaneous exposure of plants to light in the deep red and far-red spectra Deep Red 660 nm /Far-Red 700 nm . A bit of boring science that explains why you need both far red and deep red in order to trigger Emerson. The effect occurs because photosynthesis is driven by two distinct pigment systems working in series:Photosystem II (PSII): Absorbs energy most efficiently at shorter wavelengths (higher frequencies), like 680 nm (441 THz). Photosystem I (PSI): Absorbs energy most efficiently at longer wavelengths (lower frequencies), specifically 700 nm (428 THz). When you provide only the higher frequency (deep red), PSI becomes a bottleneck. When you provide only the lower frequency (far-red), PSII is not sufficiently excited to provide electrons. Providing both frequencies simultaneously allows both systems to work at peak efficiency, resulting in a rate of photosynthesis that is greater than the sum of the two lights used individually. To understand the Emerson Effect, think of photosynthesis not as a single engine, but as a two-stage assembly line. What is the Emerson Effect? Discovered by Robert Emerson in 1957, this phenomenon shows that plants perform photosynthesis much more efficiently when they are hit by two specific types of light at the same time: Deep Red (660 nm) and Far-Red (700+ nm). If you give a plant only Far-Red light, photosynthesis is very slow. If you give it only Deep Red, it's better but still limited. However, when you give it both at once, the total rate of photosynthesis is significantly higher than if you just added the two results together (1+1=3). What is Happening? (The "Assembly Line") Inside the plant's chloroplasts, there are two "workstations" called Photosystem II (PSII) and Photosystem I (PSI). They work in series, meaning the first one must pass "parts" to the second one. PSII (The First Station): This station is tuned to catch Deep Red light (660 nm). It harvests electrons from water. PSI (The Second Station): This station is tuned to catch Far-Red light (700 nm). It takes the electrons from the first station and uses them to create energy (ATP and NADPH). The Problem: If you only provide Deep Red light, the first station works fast, but the second station can't keep up because it isn't being "powered" efficiently by that specific frequency. This creates a traffic jam of electrons. The Solution: By adding Far-Red light, you power up the second station. It now "pulls" the electrons from the first station much faster, clearing the traffic jam and making the whole assembly line run at full speed. The Benefits for The Grow.. Because i am using the Biotabs water-only method, my plants already have a steady supply of organic nutrients. Implementing the Emerson Effect offers several distinct advantages: Increased Biomass: Because the "engine" is running faster, the plant produces more sugars and carbohydrates, leading to heavier fruits or flowers. Faster Finishing: Plants often reach maturity sooner because they have more surplus energy to complete their life cycle. Better Light Penetration: Far-Red light is very good at passing through the upper leaves. This "wakes up" the lower parts of the plant that would otherwise be shaded, allowing the whole plant to contribute to growth. Enhanced Secondary Metabolites: In many crops, this synergistic light can stimulate the production of terpenes and antioxidants, improving the "quality" (smell, taste, and potency) of the final harvest. The "Sunrise/Sunset" Trick I am using 4x Invisible sun Far red/Deep red bars,they use high-quality Samsung LH351H (660nm Deep Red) and specific Far-Red (730nm) diodes for 10–15 minutes at the start or end of the light cycle. This mimics the natural shift in light at sunrise and sunset, "waking up" the photosystems or signaling the plant to go into "sleep mode" faster, which can further optimize the flowering cycle. Enviromentally i am chasing a VPD of about 1,1kpa. My room seem to sit nicely at lights on at 24c with no real drama and a little help from a 220W greenhouse bar radiator. Its using abot 4kw/h a day atm because my room is attached to the side of my house and its been -5c.. I have had to add some humidity as its also very dry atm. Im aiming for RH of 65% with my 24c but it is more around the 62s.. VPD is crucial and is the focus for this grow for me. The autopots and Biotabs make it so easy ican really just focus on perfect enviroment. A VPD of 1.0–1.2 kPa provides enough "atmospheric pull" to move calcium and magnesium up from the roots, which is critical for the rapid cell division happening now.. Plants will be flipped on Saturday which is their week 5 as im a bit behind.. As this happens i will push PPFD upto 4-500umols. by week 2 of flower. Thats the plan anyway..