This is our first year to grow Freedom Red poinsettia, only half the crop has great color. I separated them so I could turn down the heat on the ones in color and keep the others that need to color up. We have had very cloudy weather with low light levels I think that is why they stopped gaining color, so I bought some high preasure sodium lamps and now have about 7000 lux for light. Will this help me to bring them color? About 4500 lux is my natural light. Every table in the greenhouse has its own hot water heat so I am keeping these tables at about 71 or 72 day and night. Can you help me? If I can get them to color up I'm sure we can sell them even up to Jan 1, 2008. I will send pictures once I figure out how to do it.
Thank so much. Matthew

Matthew, thank you for detailing the program you are currently using to get your plants into bloom. There are several things that might cause them not to flower properly, so please check to see which of these might apply. First, we have to assume that unless the plants had different conditions (temperatures / light / etc.) that would be the cause of them not flowering uniformly there must be other factors involved. These might include:
1. Plant growth regulators applied late into the development stage or at rates that are too high could be responsible for some not blooming, especially if you applied these to the roots.
2. Low levels of root rot disease (not enough to kill the plant but enough to cause some root loss) can cause a significant delay of plants.
The use of lights to help bring plants along is good, at this stage you should be able to run these lights for about 14 hours to push the plants along. Also, keep the soil a bit dry (not enough to cause wilting), this will help. Keep us posted on response. Jack