|MadSci Network: Botany|
Hi: You asked a broad question. The length of exposure time to light, blue light, red light and far-red light indeed play very important role in regulation of plant growth and flower development, but the effects are relative to the affecting time of lights. For example, cocklebue flowers only when dark time exceeds 8.5 hours per day, but many wheat can only flower when a critical day length has been reached. For some plants, far-red light can promote flower while in other plants it will inhibit. Since I do not know what kind of plants you are growing, I can not simplely "yes" or "no". However, I think the soft white floresent bulb your are using is enough for most kinds of plants, at least in my case ( I grow Arabidopsis) it is sufficient.
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