Ushio HiLux Gro CMH Lamp 315W 4200K | 520 µmol/s, CRI >95 Veg

Ushio HiLux Gro CMH lamp 315W 4200K for the veg side of the room

Ushio built this one for the part of the room where clones turn into plants. It is the cool-spectrum HiLux Gro ceramic metal halide lamp, model CMH-315W/942/AGRO, product number 5002537. Ushio rates it at 32,000 lumens after 100 hours and 100 lm/W, with colour rendering above CRI 95. Its brochure lists 520 µmol/s of PPF, about a sixth less than the warm lamp in the same line. That gap is the cost of a bluer spectrum. Electrically it matches its sibling, running at 100V and 3.15A with a 4.7A starting current and a 4 to 5 kV strike. It sits on a PGZX18 base in a clear, double-envelope T12 bulb, 193 mm overall. Ushio rates it for open or enclosed fixtures and any angle from base-up to horizontal. Rated life is 15,000 hours on ten-hour starts, and a hot restart takes 6 to 8 minutes. It wants an ANSI C182/O-rated ballast or an electronic CMH ballast.

A 4200K lamp for the vegetative stage and full-cycle tents

At this colour temperature the lamp sits on the line between transitional and vegetative light. That is why growers run it in veg rooms and in single-lamp tents that carry plants from start to finish. The blue-rich output tends to keep internodes tight and stems thick under a young canopy. Its high colour rendering also makes it the easier lamp to scout under, because leaf colour looks close to daylight. Hang it higher over fresh clones, then bring it down as roots take hold and new leaves harden off. In our own ten-lamp CMH comparison it placed ninth on summed PAR, and its UV reading landed in the lower half of the group. So it is not the lamp to pick for maximum photons in flower. Switch to the warm HiLux Gro at flip if you want more output and more UV, or run one of each to mix spectra. Drive it with a low-frequency CMH ballast, since standard HPS and MH ballasts will not run it. It is sold as a lamp only, with the socket, reflector and ballast sourced separately.

Key Features

• CRI >95 Daylight Rendering: Leaf colour reads true under the lamp, which makes deficiencies and pests easier to spot.
• 520 µmol/s PPF: Ushio's published photon output keeps a veg canopy growing at a steady pace.
• 4200K Veg and Full-Cycle Spectrum: Blue-rich light supports compact structure through vegetative growth.
• 15,000-Hour Rated Life: Long rated life on ten-hour starts carries many veg cycles before replacement.
• PGZX18, Open or Enclosed: The standard single-ended 315W base fits common CMH reflectors either way.
• Matched 3000K Sibling: The warm HiLux Gro lamp uses the same base and ballast for an easy swap at flip.

Technical Specifications