I keep my dragons in my office, where i often have the lights on late b/c i have an online volunteer job that takes up a lot of my evenings. I have found that if i turn the lights off early and close the door, and leave the lights off for about an hour, my dragons will fall asleep and not wake back up even when i turn the lights back on, no matter how long i have them on for. I dont know if its just a fluke and my dragons are weird, but you could try that if the blanket thing is too unweildy for you or whatever. Mine also fall asleep in the evening with their overhead lights on, as long as all the other lights in the room are off. Thier natural bedtime seems to be about 8pm now that the days have gotten shorter, and about 9 -10 pm in the summertime.
Good luck!
Jamie
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Jamie A. Stine and the Gang:
1.1 Bearded Dragons (Lancelot & Guenivere)
0.1 Borneo Short Tailed Python (Ezmerelda)
0.1 Red Tailed Boa (Buffy)
1.1 Cook's Tree Boas (Sharon & Ozzy)
1.0 Short Tailed O'possum (Jethro)
1.2 Guinea Pigs (Bud, Buffy, & Belinda)
1.0 Greyhound (Hank)