Apart from the junk shops, a number of craft shops sell paint for painting
designs on light bulbs or glass. If you covered the bulb with this green
paint you will have green bulbs. You can often buy painted bulbs at markets,
get the seller to do a couple for you in green only.

Hope this helps,
Peter

"rapdor" wrote in message
...
Thanks for the illuminating lesson.

But I have apparently not made myself clear. We are going to grow the
seedlings in total darkness, ie., we do not want light for plant growth.
We want to exclude all light. But of course need to see what we are
doing.
Green light does not affect plant growth, so that's what we need. Such a
product does exist, I'm positive. But where to find it, that's the
question.