Bulb HPS/MH

Our HPS and MH bulb range

Indoor growers have relied on HPS and MH bulbs for decades, and for good reason: no other lighting technology delivers this much usable light energy at such a low cost per harvest. At Plant & Flower, your Belgian grow shop since 2011, we stock the full range. Browse our 150/250W bulbs, 400W models and 600W bulbs to find what suits your space.

HPS and MH: proven indoor lighting that delivers

High Intensity Discharge lighting remains the backbone of productive indoor gardens worldwide. Metal Halide (MH) bulbs emit a cool blue-white spectrum that mimics spring sunlight, driving compact vegetative growth with tight internodal spacing. High Pressure Sodium (HPS) bulbs produce a warm red-orange spectrum similar to autumn light, triggering intense flowering and fruit production. Together they form a complete lighting solution covering the entire plant life cycle. Plants primarily absorb blue wavelengths (400-500 nm) during vegetative growth and red wavelengths (600-700 nm) during flowering.

Technical specifications that matter

• E40 base: universal standard, compatible with virtually all reflectors on the market
• MH spectrum: 6000-6500 K, blue-dominant, ideal for vegetative growth
• HPS spectrum: 2000-2200 K, red-orange dominant, optimised for flowering
• Efficiency: 100-150 lumens per watt depending on model (Philips GreenPower hits 150+ lm/W)
• Lifespan: 10,000-15,000 hours, but spectral degradation justifies replacement every 3-5 cycles
• Ballast pairing: ballast with matching wattage required (400W bulb = 400W ballast)

Popular models and wattage selection

For small tents 60 × 60 to 80 × 80 cm, the Sylvania Grolux 250W or the Lumatek HPS 250W cover the requirements with manageable heat. For 100 × 100 to 120 × 120 cm, the Lumatek HPS 400W offers an excellent balance between power and thermal management. The professional reference remains the Philips GreenPower 600W for 120 × 120 to 150 × 150 cm, delivering the best lumen-per-watt efficiency on the market. For vegetative growth in larger tents, the Lumatek MH 600W provides vigorous growth, and the Sylvania Grolux 600W delivers an HPS spectrum optimised for flowering.

Installation and maintenance

Always handle bulbs with a clean cloth — fingerprints create hot spots on the glass that weaken the arc tube. Hang the bulb 40-50 cm above the canopy for 400-600W models (verify with the hand rule: if the heat is uncomfortably intense, the bulb hangs too close). Discharge bulbs gradually lose their spectral quality even when they still ignite — replace every 3-5 cycles depending on usage intensity. A clean reflector also optimises light distribution throughout the entire space.

FAQ - Frequently asked questions about HPS and MH bulbs

Browse our complete range of HPS and MH bulbs at Plant & Flower, with fast delivery throughout Belgium. Our team gladly advises on choosing the right wattage and spectrum for your tent and grow phase.