OK to switch to gritty mix?
I have several potted ficus lyrata that are growing relatively well in traditional soil but each have several leaves that are browning at the edges. I'm itching to try Al's gritty mix and was wondering if now is an OK time to switch. I repotted them into slightly larger containers when I first bought them in May but that was right back into traditional soil. I've never fertilized them (forgive me, I'm new to this) and I'm off to pick up some Foliage Pro this afternoon. I'm just eager to try some of the great tips that I've learned on this forum but don't want to do too much too soon and stress my trees.
Any thoughts? I appreciate any and all input :)