Philips

High Pressure Sodium lamp with clear tubular outer bulb, high output and long reliable lifetime

High Pressure Sodium lights produce an orange/red spectrum and is best for flowering plants.

The orange-red light stimulates plant hormones and encourages it to flower.

The best way to light your grow room is with a combination of blue and red/orange light, to keep plants compact and flowering happily.

This is best done by using a Halide then changing to a Son T style HPS or by using a multi-spectrum lamp.

Plant growth (photosynthesis) is not then determined by lux or energy, but by the photons from the blue to red (400–700 nm) part of the spectrum.

This is called growth light! For horticulture, natural daylight (global radiation) is in most cases measured in terms of energy (J or W) with a solar meter.

This meter is generally positioned on top of the greenhouse.

The value of global radiation is important for climate and humidity control in the greenhouse.

Extremely high quality sodium bulbs that produce slightly more lumens than standard models and last much better than the competition.