Uvb

[Chad C]

Do I need uvb light for a 9year old Hermanns tortoise while indoors for the winter?

 

[Alex and the Redfoot]

Hello!
I guess, you plan to keep him awake through the winter? Then yes, I would add a UVB lamp.

Even if brumate (hibernate) him and I can trust Wikipedia on climate data, your tortoise will spend about 6 months indoors and UV index is comparably low most time of the year. So indoor UVB source and occasional calcium with D3 supplement would be nice to have, anyways.