Spiritus Sancti mysteriously ailing - help!
I have an approximately 2-year-old Spiritus Sancti that I've had since it was a start. Overall, it has grown well, regularly producing new leaves that are healthy and robust. It was a bit leggy until I dialed in the lighting. I've kept it in a Berg's Potter 4-inch pot until recently transplanting into a 6-inch.
Before I transplanted, its older leaves started showing signs of yellowing. I didn't think much of it, as it hadn't dropped aging leaves in a while, and the yellowing seemed isolated to the bottom half of the plant. However, now most of the plant's lower leaves are yellowing and looking sickly without an obvious cause, and I'm getting more concerned. I have inspected it closely for pests and examined the roots when I transplanted, but haven't seen any issues. It did recently produce a new leaf, and that one appears healthy.
Parameters: bright indirect light by an east-facing window that receives morning sun but is shielded from the afternoon's rays, supplemented in the evening with a grow light. Soil is a special aroid mix. I regularly water when the top couple inches of the soil are dry, with occasional longer intervals to help keep the roots oxygenated. I was fertilizing with a soluble fertilizer before the transplant, but have since stopped given the fresh soil.
Photos shown are NOT where it is typically placed; it is nestled with other plants for humidity (sits usually at around 50-60%), and I pulled it out to get good photos of the leaves. Included are images of both its sicker leaves and a healthy one.
If anyone has experienced this with their Spiritus or another philo and has a solution, I'm all ears.
TIA!
