Why my orchid leaves are yellowing?

[KC Kam]

Greetings all,

I need some advice...

I have an cattleya orchid that was under my care for 2 years and has been blooming twice too. The 2nd time bloom was after i moved it to a new location..practically just 2 feet away. However, recently it leaves turn yellow. Orchid leaves usually turn yellow from the oldest bulb but in my case it is not. Not only it didnt drop leaves from oldest bulb but few pseudobulb leaves turn yellow and dropped.

Do you think is due to watering or some fungi / bacteria attack?

Please help to advice

Thanks.

[Chris in Hamilton]

Are you fertilizing KC? Is the wood it is mounted on still sound or rotting?

[KC Kam]

Hi Chris,

Yup, I am fertilizing twice a week with weak dosage. The wood is mounted and is still good and solid.
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[raybark]

What fertilizer formula, and concentration are you using? What is your water supply?

Is there a difference in light intensity between the two locations?

[KC Kam]

Hi Ray,

I applied NPK 21-21-21 (0.5 gram per liter, twice a week). Water are filtered water. Light intensity in new location is lower but it still flowers with smaller flower.


Anyway, is too late...the orchid is dying. As shown in the picture, the pseudobulbs were turning yellow+brown and it is getting soft when i press it. I guess has some bacteria infection. I have to cut those that looks healthy ones out...

One of the pseudobulb has i believed infected eyes...so i have to cut that out too.

I dont know what happen and how to prevent it in the future...kind of lost....

[daenna]

It could a fungal problem which happened to my cattleya before. It occurred because of overwatering and not letting it dry out.