Nutrient decency? What am I doing wrong?!

[becky.crm]

One of my phalaenopsis' and oncidium look like they are nitrogen deficient. I fertilize with a 20-20-20 diluted to the recommended 1/4 tsp per gallon everytime I water. I don't know where to go from here. Do I bump up the fertilizer? They have been repoted recently...

Jack's Classic All Purpose 20-20-20 Water Soluble Plant Food (1.5lbs) https://www.amazon.com/dp/B001REA5NK/ref=cm_sw_r_apan_i_YWF7Y2G9JTR7FQ4RZXGX?_encoding= UTF8&psc=1

[estación seca]

Welcome to the Orchid Board!

More information needed. What kind of light are they getting? What temperatures day/night? What kind of humidity are they getting? How are you watering, and how often? How do you decide when to water? Does your water have any calcium in it? When were they last repotted?

The Phal looks as though it might be getting too much light. They prefer no more than 1,000 foot candles though they like long days from spring to fall. Phals do best in medium with large air spaces at the roots, which need air to survive. They prefer going almost but not completely dry between waterings.

The Oncidium has had issues with underwatering in the past. There is a chance it is getting too much light now. The pot is much larger than I would have used. These do need to stay moist, not drying out, but they also need air at their roots.

[claypot]

Just from your images it looks to me that both plants are in extremely wet compact compost so maybe the roots have drowned and could not breathe. The colour of the leaves indicates over watering too. The plants should have a much more open compost which allows the roots to dry out between waterings. It is just a waste of fertilizer if the roots cannot take it up, and my guess would be that if you unpot the plants you will not find any sort oif vibrant root system.

[camille1585]

Welcome to Orchidboard!
Without more information on your growing conditions it can be difficult to pinpoint the cause. Nitrogen deficiencies are rare, expecially when using fertilizer.

Orchids can become light green from too much light. I've had similar coloring on some phals when I forgot to move them away from the window at the end of winter (stronger light and it comes in sideways at that season).

What type of water are you using with your fertilizer? If it's rainwater, or you have very pure tap water, it could be other deficiencies showing up since you are only suppling N-P-K with your fertilizer.