New growth is a great sign of health, Alex.
Always keep in mind that fiddle leaf ficus plants are trees and not your "typical" houseplant. In the subtropics and tropics they grow outside in full sun. After having my fiddle for 25+ yr., constantly trimming her to keep her no more than 7' tall (so that I could get her through doors in the fall and in the spring), mine has now been acclimated to full sun (this took 4 mo.) and she's now in the ground. She's grown a foot in the last 3 mo. after she was "planted". My fiddle has 11 vertical stems, aka trunks.
Alex, if your plant is healthy and the growing conditions are favorable, she'll grow a foot each year. My plant grew a minimum of two feet each year. That growth is going to really challenge your ability to grow her under lights.
The photo is the same plant, just different lighting. The photo was taken in November and she was a little over 7' tall then. She was trimmed back to 6' in March, so that I could box her up for the move to Vero Beach.
