Uses halogen lights

I recently had extremely good success growing Hawaiian/Cotton Candy under two 500-watt halogen lamps. The yield was 100 grams and the quality was excellent. The lights are much less expensive than HPS lamps. What is the difference between the two?
Lizzie Jane,
Winnipeg, Manitoba, Canada

High pressure sodium lamps emit at least seven times more light than halogen lamps. A garden growing under a 1000-watt HPS lamp is expected to yield one pound or more. Your garden, using the same amount of electricity, yielded one tenth as much.

The initial cost of the halogen bulb is much cheaper than an HPS lamp. However, when the cost of generating light is considered, HPS lamps are much cheaper. For every dollar you spend on electricity for lighting using a halogen bulb, you pay only 14 cents or less using an HPS lamp.

In addition to the cost of electricity, consider the space being used and most importantly your time. You expend essentially the same effort to produce 100 grams rather than 400-500 grams. That alone makes a small harvest considerably more expensive than a large one.

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