Horticultural COB LED: The Game-Changing Concentrated Lighting

Horticultural COB LEDs (Chip-on-Board) are revolutionizing indoor grow lighting with their technology of multiple chips mounted on a single substrate. Unlike classic dispersed LEDs, COBs concentrate impressive light intensity over a reduced surface, creating an ultra-powerful light point perfect for precisely targeting your grow areas. This concentration allows for high PPFDs with fewer light sources.

Why choose a horticultural COB LED

COB technology offers exceptional light density that far surpasses traditional LED panels. With wattages ranging from 50W to 200W per COB, you get the equivalent of several dozen classic LEDs concentrated in a single point. The spectrum is generally optimized between 380nm and 780nm with peaks in deep red (660nm) and royal blue (450nm). Thermal management is crucial: each COB generates significant heat that requires an appropriate heatsink, often made of aluminum with fins for efficient dissipation. The beam angle varies between 60° and 120° depending on the model, allowing for precise directional lighting.

How to choose your horticultural COB LED

The wattage depends directly on your grow area. For a 60x60cm tent, count on 100-150W actual COB power. An 80x80cm will require 200-300W, and a 120x120cm will need a minimum of 400-600W. Always check the actual power consumed, not the advertised equivalent power. The full-spectrum with added far-red (730nm) boosts flowering. COBs with lenses concentrate light more but reduce the covered area – perfect for tall, dense plants. Without a lens, the spread is wider but less intense. The heatsink should be at least 3 times the size of the COB for efficient passive cooling.

Frequently Asked Questions

What wattage of horticultural COB LED should I choose for a 60x60 cm tent?

For a 0.36m² surface, aim for 100 to 150W actual horticultural COB LED power. This wattage will give you a PPFD between 400 and 600 µmol/m²/s, ideal for growth and flowering. Avoid COBs over 200W for this surface as you risk burning your plants and wasting energy. A single well-positioned 100W COB will be more effective than several small, dispersed COBs.

What distance should I maintain between my horticultural COB LED and the plants?

Maintain 30 to 50cm between your COB and the top of the plants, depending on the wattage. For a 100W COB, 40cm is sufficient. A 200W requires a minimum of 50-60cm. Monitor for signs of light stress: leaves turning white, browning edges, or stunted growth. Use a lux meter to precisely measure the intensity received by your plants. Adjust the height according to the phases: higher during growth, closer during flowering.

Are horticultural COB LEDs with lenses better for light penetration?

Lenses do indeed concentrate light and improve penetration into dense canopies, changing the angle from approximately 120° to 60°. They are perfect for tall plants with a lot of foliage. However, they reduce the illuminated surface and create more pronounced shaded areas. Without a lens, you cover a wider surface better but with less intensity in the center. The choice depends on your growing style: dense SOG or voluminous individual plants.

How to install a horticultural COB LED with its heatsink?

First, attach the COB to the heatsink with thermal paste to ensure heat transfer. Tighten the mounting screws in a cross pattern for even distribution. Connect the wires respecting polarity (red = +, black = -) and use a driver adapted to the voltage and current of your COB. Mount the assembly on an adjustable support and ensure that air circulates freely around the heatsink. A 12V fan can be added for active cooling if necessary.

How to maintain a horticultural COB LED for long-lasting performance?

Regularly clean the heatsink fins with a dry brush to prevent dust accumulation, which reduces thermal dissipation. Check electrical connections every 6 months for oxidation. Avoid thermal shock by allowing it to cool before complete shutdown. Monitor the heatsink temperature: it should never exceed 80°C to the touch. A well-cooled COB can operate for 50,000 hours, which is more than 5 years of 12h/day use. Replace the driver if you notice flickering or a decrease in intensity.