LED Grow Light Bars & Bar Arrays for Indoor Growing
LED bar array grow lights - fixtures consisting of multiple individual LED bars distributed across a frame rather than consolidated in a single panel - have become the dominant format in commercial indoor growing over the past several years. Bar arrays outperform equivalent-wattage panel LEDs on canopy uniformity by distributing light across the full width and length of the canopy footprint, reducing the center-to-edge PPFD gradient that single-source panels produce over large growing areas. For serious hobby grows and commercial operations targeting consistent yields across the full canopy, bar arrays represent the current state of the art in LED grow light design.
Why Bar Arrays Outperform Panels for Larger Canopies
In a single-source LED panel or COB fixture, all photons originate from one point and spread outward - producing a PPFD map that is highest directly below the fixture and tapers toward the canopy edges. Over a 4x4 canopy, a quality panel might produce 1,100 umol/m2/s at the center and 700 umol/m2/s at the corners - a 37% gradient. A six-bar LED array distributing the same total photon output across the full 4x4 footprint produces 1,000 umol/m2/s at center and 900 umol/m2/s at corners - a 10% gradient. The more uniform PPFD distribution produces more even plant development, more consistent canopy quality, and reduces the need to rotate containers to equalize light exposure. For 4x4 canopies and above, bar arrays consistently outperform panels on uniformity; below 3x3, the difference is less significant. Use our PPFD & Light Coverage Calculator to compare specific fixtures.
Commercial LED Bar Brands
The commercial LED bar array category is covered by a range of qualified brands at Hydrobuilder. Gavita (Pro 1700e LED and higher wattage models) is the most widely deployed commercial bar array in North America with the EL2 Master Controller ecosystem. Growers Choice (ROI-E series) delivers competitive photometric performance at lower price points. Faven Lighting offers commercial bar arrays with under-canopy supplemental bar options. HLG (Scorpion and 650R bar arrays) provides quantum board bar options from hobby to commercial scale. All are available individually or through our commercial accounts program for volume configurations. Expert support available.
LED Grow Light Bars FAQ
What is the difference between LED bar lights and LED panels?
LED bar arrays distribute multiple individual LED bars across a wide frame, spreading photon output evenly across the canopy footprint and reducing center-to-edge PPFD gradients. LED panels concentrate output from one integrated board or COB source, producing higher center PPFD that tapers toward edges. For canopies 4x4 ft and above, bar arrays produce measurably better uniformity - consistent PPFD across the full canopy area produces more even plant development and eliminates the need to rotate plants. For smaller canopies (2x2 to 3x3 ft), quality panels perform comparably to bar arrays and are typically more cost-effective at the same output level.
How many LED bars do commercial grow light fixtures typically use?
Most commercial LED bar arrays for 4x4 to 5x5 ft canopy coverage use 5-8 individual LED bars per fixture. Gavita's Pro 1700e uses six bars. Growers Choice ROI-E720 uses eight bars. HLG's 650R uses six bars. More bars with narrower spacing produce better uniformity across the covered footprint; fewer wider bars save cost but can produce more visible PPFD variation between bars. For commercial applications where canopy uniformity directly affects harvest consistency, higher bar count fixtures from premium brands justify the cost premium over lower-bar-count alternatives.
Can LED bars be dimmed?
Yes - all commercial-grade LED bar arrays from qualified brands (Gavita, Growers Choice, Faven, HLG Scorpion/650R) accept 0-10V analog dimming input, enabling automated dimming via compatible controllers like TrolMaster Hydro-X. Dimming capability allows growers to reduce intensity during vegetative growth (lower PPFD requirement, less heat, less electricity), ramp up to full power at flower initiation, and reduce output automatically when canopy temperature exceeds a setpoint. Gavita fixtures additionally support the EL2 Master Controller protocol for up to 80-fixture coordinated management. Confirm your specific model's dimming input specifications before purchasing a controller.
