"Don't look at your age, but focus on what you can do for the world, share what you have to benefit mankind, you'll succeed if you'll see others you've helped reap success. Share more to earn more".
Yes, you're right, you've to thin them out, change your soil media and replant them in a new soil rich in organic matter.
When replanting them, place them in a shady area until they are fully establsihed and transfer them to an open place with enough sunlight.
Happy gardening.
Cris
