Yellow Spot on Phalaepnosis

[OrchidMan101]

I previously made a post about a newly purchased Phalaepnosis and how it had some yellow spots on its leaves after a few days/a week of keeping an eye on the orchid it seemed to be good, no new spots. But as of today, which is probably more than 2/3 weeks after I made that post, I found 2 more small spots. So I’m currently under the opinion that the orchid has some type of virus/ infection. Thoughts?

[Shadeflower]

A spot like that would not make me think virus.

What I would be checking is the ph and the runoff salts coming out of the pot after flushing.

So I need to ask what is the ph of the water you are watering with?
How much are you fertilizing?

It might not be related to your water quality but I'd start my investigation there.

Do you notice the crack in the leaf? Yes it is mechanical damage but it's a sign of an underlying issue, a healthy leaf should not be that brittle for it to crack.

[estación seca]

What is the potting medium? What are your temperatures day/night? Humidity? What kind of light is it getting? How are you watering?

Phal leaves cracking down the middle are usually caused by insufficient water.

[OrchidMan101]

The ph of the water I’m watering with is around 7.5 and since it was was planted in pure sphagnum moss I haven’t been watering and fertilizing much. I fertilize around every 2-3 weeks.

---------- Post added at 08:07 AM ---------- Previous post was at 08:01 AM ----------

It was potted in pure sphagnum moss, daytime temp is somewhere in the 70’s and nighttime temp is around 65, it gets light from a north east window, and since it’s in pure sphagnum moss and I don’t want to overwater, I’ve been watering every 4-6 days with enough water so the roots turn green but not enough so the whole pot is drenched and water runs out the bottom.

[tmoney]

well, we don’t grow in all sphagnum, but in that, watering every 4-6 days seems like a lot. our phals are in super airy bark and we only water every 7 days, even going to 8 now that the temp is a bit lower.

probly has nothing to do with the spots, but it just seemed like a lot. do you just dribble a tiny bit of water on the top when you water, or do you full on soak it? just curious, thanks, and good luck with the spots!

[OrchidMan101]

Just a dribble

[estación seca]

It sounds like you're watering properly. They won't grow much at lower temperatures like that, so you probably don't need to fertilize more than monthly.

I don't know what the yellow spots are. I would consider using a heating mat to warm it a little. Phals survive and grow much better with warmer temperatures.

[Shadeflower]

you need to fertilize with an overall concentration of 800ppm if fertilziing monthly. 200ppm if fertilizing weekly and 400 ppm if you are fertilizing every 2 weeks.

7.5 ph is too high. It should be between 5.8 and 6.5 so if you can adjust it, that will improve things a lot.

I am suspecting you are fertilizing too little/flushing too much.

Get a tds meter. Aim for a concentration of 400-600ppm if feeding every 2 weeks. That is quite strong in fertilizer terms but it has to be compared to someone who fertilizes on every watering. They need to receive a basic amount in a year and if fertilzing as little as every 3 weeks it needs to be 3 times as strong otherwise "fertlzing little" will result in a spot turning into a yellow leaf over time.

To give a comparrison where the nutrient concentrations fit in:

algae and aqautic plants: 20ppm
Orchids: 120-200ppm
Orchids fed monthly: 800ppm
Tomatoes: 1000-1200ppm

[estación seca]

Phal growing is not complicated. Don't be frightened away. Warm temperatures, tap water and small amounts of plant food are adequate for nice Phal growth and flowering.