I have a question regarding dark period interruption. I am growing 3 small females in my backyard and they started flowering about 4 weeks ago. I have a small backyard and when I go out at night or let my dogs out I turn on the back porch light (standard 60w bulb) that is about 10-15' away from my plants. Will having this light off/on throughout the first 3-5 hours of my dark period have any ill effects on my bloom? Will this amount of light prevent my flowers from fully developing? Thanks.
If you didn't want to seem suspicious for having an odd colored bulb, is there any way you could put up some kind of light diffusing screen or a trellis between the plants and the light source to diminish the light? Colored bulbs don't offer a 100 percent guarantee against hermi or poor growth pattern, some plants are more sensitive than others and a majority will show some amount of ill effect from frequent dark interruption. A colored bulb will also give you slightly less visibility than a white or clear bulb. They do make 15 watt bulbs, but it depends how much visibility you want; enough to 'see', or just enough to take a few steps out, turn around, and have a small night-light so you can tell where the house is. If you could get by with that, using a 15 watt would be your best bet. The smaller the light, and any barrier you can put between it and the plant, the better your chances of success are.
Wait you're growing outdoors? If you're growing outdoors I wouldn't think this would be a problem. No outdoor plant gets 12 hours of complete darkness. The moon and stars cancels that out. The 12 hours of complete darkness is for indoor growers because they force the plant to veg/flower, etc... manipulating everything. Outdoors I wouldn't think you'd have a problem. I could be wrong. Indoor grower.
The plant doesn't know if it's indoors or out, it is responding to external stimuli that trigger hormonal responses. One of those external stimuli is the amount of dark and the amount of light, so the key is to make sure you stay under that. Even a full moon gives off very little light -- it looks "bright" to our eyes because of the contrast against the night sky, but we perceive light rather than experience it directly. I don't think a single 60w incandescent from 10-15' away will affect the plant, just too little light for it to respond to, but I can't say for sure so to be safe I agree with trying a green bulb and/or blocking the light from the plants somehow. I don't think that a green light bulb is suspicious in and of itself, but keep in mind that the light from a green light bulb may look all green to our eyes but may not be all green -- since it is not green from the source but is a white light filtering through colored glass there still could be other color spectra mixed in there that we don't see.
Thanks guys. I wasn't too sure on this, and although I'm still not, I can try to incorporate some of these ideas. The light-bulb is in an enclosure that can be moved in directions as to where you want your light source focused, so it is shining away from the plants, but I just wasn't sure if the indirect light source would be enough to alter my flowering cycle. Like I said, these girls started flowering about 4 wks ago and so far they look great! I had considered moving my pots to a darker area every evening and back to their sun spot in the morning, but I could see that becoming a hassle.
I'm kinda interested in this some more as I"m growing a sativa that can get 20' outdoors. If Cali passes the law, I plan on planting it outdoors and just seeing how high it gets. I thought outdoor grows were much like autoflowers, as in, outdoors they know naturally when they should be harvested, and light cycles were not an issue.
The light cycle first, then temperature, are both very important aspects of the environment that control when a plant is in veg, and when a plant begins to bloom (except of course in the case of autos), what we do is try to mimic the same cycle indoors that the plants experience outside. If the town or city installs a street light too near your grow during bloom (and with powerful street lights 'too close' is further away than you'd think), they'll either hermy, or attempt to revert back into a vegetative state. If the light is already present during the onset of flower, the plants may slowly 'flower' but never fully mature with that light present during their dark period. I've known a few growers who had pounds and pounds ruined this way.. one of the benefits of growing outside, but still within buckets, is that if this or anything else happens you can move your plants to a healthier safer location.