1000W Metal Halide in Small Greenhouse: Heat, Placement, and Fixture Concerns

A grower installed a 1000W metal halide in an 8×6 ft greenhouse for plants from our nursery. Concerns: heat, light intensity, bulb selection.

Major Concerns

• Heat/UV intensity: Plants must be 5-6 feet from bulb to avoid burning. In an 8×6 ft house, 1000W is likely too large.
• Better alternative: One or two 400W bulbs strategically placed for even coverage. We use three 400W fixtures in our greenhouses.
• If keeping 1000W: Install moving track to sweep fixture across house (we do this in sundew house, 8 ft/minute).

Fixture Rating Critical

Standard workshop fixtures aren't rated for damp environments. Water splash on hot bulb causes explosion. Water only when lights are off, or use horticultural-rated fixtures.

Resource

Metal halide info: homeharvest.com. Upcoming podcast on this topic.

Right-size your lighting; 1000W in small space is hazardous.