If you're looking for under-canopy grow lights to supplement your main lighting (like the Luxx 645 LED Pro), you’ll want low-profile, efficient LEDs that provide targeted spectrum and intensity to lower branches. Here are some top options:

Best Under-Canopy Grow Lights

1. LED Light Bars (Low-Intensity, Full Spectrum)

• Spider Farmer SF Series (SF600, SF1000)

• Slim design, daisy-chainable.

• Full spectrum with Samsung LM301B diodes.

• Good for side-lighting or lower canopy penetration.

• HLG Saber (100W or 200W)

• High-efficiency, waterproof (IP65).

• Ideal for vertical racks or tight spaces.

2. Far-Red & Deep Red Boosters (For Flowering)

• PhotonTek 300W Far Red LED

• Enhances flowering & Emerson effect (better bud development).

• Best used last 10-15 mins of light cycle.

• Growers Choice ROI-E420 Far Red Bar

• 730nm far-red for stretch control & ripening.

3. Flexible LED Strips (DIY or Modular)

• Bridgelux EB Gen 3 Strips

• Can be wired under shelves or around stems.

• Tunable spectrum (3000K-5000K).

• Horticulture Lighting Group (HLG) Quantum Boards

• Thin, powerful, and dimmable.

4. Clip-On LED Grow Lights (Small Plants)

• Mars Hydro FC-3000 (Mini Version)

• Adjustable arms for precision lighting.

• ViparSpectra P600

• Budget-friendly, low-heat option.

Key Considerations for Under-Canopy Lighting

Spectrum:

• Blue (450nm) for bushier growth (veg).

• Red (660nm) + Far-Red (730nm) for flowering.

Placement:

• 12-24 inches from lower branches (adjust for heat).

• Avoid light burn—use dimmers if needed.

Power & Coverage:

• 50-150W per 2-3 sq ft (depends on crop).

• PPFD 100-300 µmol/m²/s (supplemental range).

Heat Management:

• Passive cooling (fanless) is best for tight spaces.

Best Use Cases

• Cannabis: Boosts lower bud sites (lollipopping technique).

• Tomatoes/Peppers: Prevents shade-induced yield loss.

• Vertical Farming: Fills light gaps in multi-tier setups.

Final Recommendation

For high-intensity crops (like cannabis) under a Luxx 645 LED Pro, pair with:

1. Far-red bars (PhotonTek/Growers Choice) for flowering.

2. Slim LED bars (Spider Farmer/HLG Saber) for side lighting.

For moderate needs (herbs, leafy greens), Bridgelux strips or clip-on LEDs work well.

Would you like a specific PPFD layout for your grow space?