If you found this post, the chance you are struggling with the plant is pretty high. Just like you, I was attracted to the beauty of this plant. I mean, how can you say no to a perfect heart shape, the velvetiness and the paint-stroke venation? Ans just like all of you, I wasn't prepare for all the headaches it brings when caring for this diva. Unlike her easy going cousins, philodendron luxurians needs a lot of hydration. She will not settle with even a bit of dryness. if the leaves or roots feel dry, they will throw tantrums like no tomorrow. You might see crispy edges, leaf wilting, leaf dropping.
Now you might think high humidity or constant watering will solve all the problems. Quite the opposite! When you over water the plant, she will get root rots fast because of her fine delicate root system. When you leave her in a high humidity environment with little air flow like a terrarium, her leaves will melt. It seems like everything you do will piss her off.
Luckily, I have two solutions for you.
First one is very tiny sweet spot where she can be happy. That sweet spot is the combination of high humidity and great airflow. You can leave her in a greenhouse with a lot of air circulate. The key is never let water condense on the leaves for a long time. By long time I mean, 1 or two hours. Also, do not blast her with high light. A medium light will work best for her. Keep the potting medium damp, but not soggy wet. Never let the medium dry. When you fertilize, use the reduced strength. The chemicals in the fertilizer might mess up the ph balance and freak the plant out.
If that seems a lot of work to you, I have the second solution, much less work. Let her die. I am serious. Well, not completely die, but let all the leaf die back if they choose to do so. Let she throws as much tantrums as she want. And when She will finally acclimate to your home environment. Her new leaves will be less sensitive. Her roots will grow stronger and you ended up with a more resilient plant.
I know, the second solution is not everyone's cup of tea, especially when you spend a lot of money for those beautiful leaves. So I have a third solution for you: acclimate her slowly. I have a whole series on how to acclimate finicky plants from high humidity environments to low humidity conditions. You can read more about it here: https://www.instagram.com/leafysoulmates/guide/how-to-acclimate-plants-to-your-home/17960126887436671/