It's at least 8 months old...probably closer to a year! The shell looks like it was started out dry. Your substrate is a good choice...just make sure the humidity is in the 90-100% range...and soak him/her at least an hour twice a day...don't wanna see that pyramiding on the carapace continue! Planting seeds in the enclosure is a waste...they'll draw bugs and he'll gobble 'em up as soon as they sprout! Lose the greens...do this instead!
https://tortoiseforum.org/threads/to...4/#post-176333