Panic

[Chromophore]

Day 20 of flowering. Like an idiot I left two 25watt UVB cfl lamps on during dark cycle. Didn't notice until the HPS lights came back on. So, 12 hrs of 50 watts of UVB CFL on my budding plants during the dark cycle. Without devolving into a debate about the usefulness of UVB (I'm dismantling them as I type) do any of you have an opinion as to whether the flowering cycle has been disrupted, and if so what should/can I do?

[d00g]

Chrysanthemums are an example whose growth patterns and flowering behaviors have been studied extensively by the greenhouse industry. Researchers found that the largest flowers with the highest total weight are grown when the dark-cycle routine is provided each night. When the plants were in darkness only six nights a week, there was a slight diminution of flower size and total weight. With each additional lost night, flower size and weight dropped.

Without consistent dark periods of sufficient light, cannabis buds elongate and grow looser. Every time the dark period of the flowering cycle is interrupted, there is a slight loss of flowering-growing time and thus of yield. A spate of light interruptions of the dark cycle may also stress the plant to the point that it becomes hermaphroditic.
-- Ed Rosenthal's Marijuana's Grower's Handbook

Going by the quote from this book, it sounds like repeated nights of irregular light is more likely to cause hermies and you should be ok from one error. But I haven't even reached flowering stage in my first grow yet so I don't know from experience. You are very knowledgeable in your other posts so I assume your plants are otherwise unstressed, and I bet and hope they will be fine!

[Hotshot123]

Does that also apply to Auto Flowering plants? The information I have gather on them say that they need more light, and lest dark. Justing wondering.

[OMB]

I think you will be fine Chromophore. I can't imagine a single night interruption is going to do anything. I have a buddy who grows and when he goes out of town for a few day's, he just shuts everything off! No hassles with needing someone to be plant tender while he's gone....He has been doing it for year's with no apparent problems.
Same strain, so he knows it well enough to recognize any issues from that....But that's Just me, and I don't know crap, but I think you are fine brother.

[Shovelhandle]

I think you will be fine Chromophore. I can't imagine a single night interruption is going to do anything. I have a buddy who grows and when he goes out of town for a few day's, he just shuts everything off! No hassles with needing someone to be plant tender while he's gone....He has been doing it for year's with no apparent problems.
Same strain, so he knows it well enough to recognize any issues from that....But that's Just me, and I don't know crap, but I think you are fine brother.

leaving the grow in the dark is different than interrupting the dark cycle. That said, you're correct about one incident not being a concern for Chromo

[Chromophore]

Thanks for all your replies. I feel much better after reading them. I literally had difficulty sleeping last night worrying about what I had done. My main concern was that I had halted the flowering process and essentially ruined the budding. In addition to your posts, I read elsewhere stories of people leaving their plants in the care of roommates who left the lights on for several days with no obvious ill effects. I'm beginning to think that the hermaphrodite formation may be linked to other stresses as well, and seems to be a problem with plants that have such dense canopies that some lowers flower receive insufficient light. I will be watching them carefully to see if anything odd develops.

[Chromophore]

From Ilovegrowingmarijuana.com, FWIW


Dark cycle interrupted

Problem: The lights were left on for one or more days.
Symptoms: If the light is only left on for a single day, you wonâ??t really see much difference. But, if the lights are left on for a few days straight, the plants might start regressing back to vegetative growth during the early stages of flowering. Too much light exposure has less effect as the plants near maturity.
Solution: Get the cycle back to normal as soon as possible. This will prevent the plants from incurring any more damage. If the plants have reverted even a little bit to vegetative growth, the buds will obviously take a little longer to reach full maturity.

Problem: The lights were left off for one or more days.
Symptoms: Buds will ripen faster.
Solution: Simply turn the lights back on an continue the normal flowering schedule until the buds are ripe.

Problem: The lights were turned off and on irregularly.
Symptoms: Youâ??ll find lanky, irregular buds and an increased probability of hermaphroditism. See Hermaphroditism for more information.
Solution: Use a timer to ensure that the light regimen remains consistent and helps the buds grow and gain potency.

[d00g]

Good, hopefully disaster totally averted! Keep us posted if there are any changes.