Phal gigantea
 

Hi, my phal has been in semi- hydro since the end of March and it just doesn't look happy. We've had a chilly spring, and it's only now hitting 80 degrees in the house. So I am wondering if the yellowed leaf is most likely;

1. Too cold?

2. Water got in the crown?

3. Illness (bacteria, fungal or virus)

4. Too much light (gets LED blurple light)

5. Other?

Thanks for any opinions and help

Top leaf grew about an inch since I got it, but but it seems like it stopped growing. Note, room was in the high 50's and low 60's dropping to low 50's over those few months before I thought to bring in a heater. I hope this isn't something it can't quickly outgrow??!!

50s-60s is too cold for this species, even more so when potted in S/H, which further cools the root system. Ideally they like temps in the high 80s to low 90s, but grow fairly well at lower temps too (normal intermediate house temps), though will slow their growth. That being said, the plant looks overall quite good, that yellowing leaf could be normal leaf drop, but it's hard to tell from one angle.

Here are some specifics about this species that are good to know, and which you can think about in relation to your plants problems.

• It hates having its roots disturbed, and is known to sulk after repotting. A large, healthy root system is important for this species since it must support many large leaves on an older plant.
• It is prone to crown rot due to its leaves growing tightly together, so should never be watered from above or get water between the leaves. This is why it's most often grown mounted.
• Even more than other Phal species, this species will end up growing sideways if grown potted, and hang over the side of the pot. Trying to keep it upright is a losing battle.
  *Unlike most Phals, this species needs high light. In the wild it grows high up in the canopy, so takes Cattleya level light with good air movement.

It's hard to say anything about the stalled growth being light related, that depends on the output on the lights, duration they are on and distance to the plants. But if your other Phals are fine under those lights, then it's probably not enough light for Phal gigantea. I suspect that the low temperature it had until recently also has to do with it.

Thank you so much, @camille1585 ! I fear I've kind of goofed. I will need to repot him in the future, but will wait on that as I'm sure it would be very bad to disturb him now. I'll wait untill he outgrows this pot and becomes unstable or can't safely pour water in away from the plant. This will require a medium change and transplant shock :(. Hopefully the warmer temps will perk him up and next winter I'll be sure to keep him warm.

That was the worst side of the leaf, it was undoubtedly cold related. Just a little delayed in showing. I actually worry he gets too much light, but aside from light silvery leaves, there has been no sign of burning..? I'll try a spot where the lights are slightly lower and see how he feels :)