Light Pollution in Greenhouse

[BBB]

Hi everyone
I have a variety of plants growing in the greenhouse. The thing is, my greenhouse is overlooked by two HPS streetlights which never go out. The upshot of this is that my greenhouse is never completely dark.
Is this going to prevent my plants flowering? Does anybody have any similar experince? Any ideas for a solution?
I hope somebody can help.
BBB

[MikePike]

Hi there
This will almost certainly make a difference to your plants. I have had plants that would not flower effectively because their dark cycle was broken. It could even cause your plants to hermie. Is there any way you could black out the greenhouse with something during the autumn to prevent this light getting in?

[GreanyMeany]

Your plants will not be able to flower properly without a good stretch of complete darkness. Like Mike says, you're really going to need to black them out somehow. If not you may need to move them to the proper outdoors for flowering. Or bring them indoors at night time. How many and how big are they? Are they too big to move?

[Dang ol Stoner]

How big is your greenhouse? If it isn't too big, you could probably get away with throwing a large tarp over the roof and letting the ends drape over the sides. If it's a big greenhouse, consider building blackout boxes and placing your plants in them at nighttime. That way you can just leave them in the greenhouse and not have to haul them back and forth!
If all else fails...you could always take your Red Ryder and shoot out the lights!