Phragmipedium Cahaba Glow old growth looks poor

[magmachamber]

I have a Phragmipedium Cahaba Glow which is blooming for the third year. Every time the new growth matures, the old growth turns yellow and gets spots.

It is about to go into bloom now, and I will repot after it finishes.

It receives 13 hours of light at about 5000 lux. I water it thoroughly 4 times a week. The room it is has good air movement and kept at about 55% RH.

Any suggestions? Is this normal?

Thank you.

[Roberta]

Force of nature... Old growths do tend to die back once new ones mature. Once a growth has bloomed, its value to the plant is only a reserve source of energy and nutrients. So the plant draws on the old growth for the energy to make new ones. Since Phrags (and Paphs) don't have pseudobulbs, it's the old leaves that serve that function. So this is completely normal.

[magmachamber]

Thanks for your helpful response, Roberta!