flowering light

can i use a 150w HPS bulb to flower my 17in plant

You'll have to keep it pretty close, as long as you can keep the heat down

the light penetration isnt going to be as much, maybe you should try some LST on the plant if possible to get the side and to get the light closer to the plant..have more of a even canopy for that small a light

150W is more then enough for one plant.
You'll do fine, Althought you wont get as much yeild as a 400Watter.
Hoped I Helped.

-Nice Ol' Bud