Have you guys never heard of Krusty buckets? Multiple HPS (1000 watters) hung vertically in between 4 or 5 plants in a modified bubbler. Yield close to a pound a plant, if I recall correctly.

In short, yes, hps can be hung vertically. But, as Stinky said, you have to be careful that your specific bulb can be hung that way. Most modern hps bulbs are now universal. MH bulbs you got to be sure.
Perp Reviewed by Perp on . hanging your light downward i just game across a person using thier HPS light hanging down, now i never did think this would be a better way to use your light but now it has me thinking........can you possibly get better light coverage having the light between plant or atleast close to it. look at this pic. its nothing more than a 250watt light attached to a cooltube, that is a amazing grow with such a small light. would do you of this way? Rating: 5