Yeah call and talk to the garden staff them selves would be the best suggestion I can give!
The outdoor gardens are open during daylight hours. The museum was closed on the 4th and the hours are posted on the website. parksandrec.cityoftyler.org. 8am to 5 pm weekdays
that I'm not sure of however the best thing to do would be to call the Rose Garden itself and talk to somebody there to see if they are open on Thanksgiving Day which probably won't be but if you get to go it will be a great experience it's a beautiful place
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