Onc. Sharry baby normal or fungal?

[estación seca]

I would just pot up and give good care. Oncidiums tend to make new roots only from new growth.

The green pigment chlorophyll contains magnesium atoms and its formation by the plant requires iron atoms. Depending on what fertilizer you are using, be sure you're supplementing enough calcium, magnesium and iron. Many "complete" fertilizers don't have enough calcium and magnesium. Most do contain iron.

[Xylem]

Originally Posted by estación seca

I would just pot up and give good care. Oncidiums tend to make new roots only from new growth.

The green pigment chlorophyll contains magnesium atoms and its formation by the plant requires iron atoms. Depending on what fertilizer you are using, be sure you're supplementing enough calcium, magnesium and iron. Many "complete" fertilizers don't have enough calcium and magnesium. Most do contain iron.

I live in an area of England with very hard water. 200+ mg/L of Calcium carbonate. I very much doubt Magnesium would be low given they are both alkaline earth metals.

I use tap water with my fertilizer so I don't worry there will be any deficiency.

Thank you for your advice though. I will just leave it quarentined to do its thing.

[Xylem]

Okay just checking in. The nursery I bought it from (Burnham nurseries in the UK) said that the marks were just normal to sharry babys and not to worry.

What is everyone's opinion on this. Is it safe to let this the Onc be with my other orchids? The flower spike is still going strong. New growth growing fast.

Also I have prophylactically treated with castile soap so I don't think there will be pests left now.

[estación seca]

The only spots I normally see on Sharry Baby are small black and brown spots randomly scattered all over the leaves. You seem to have ruled out magnesium or calcium deficiency. I have never seen that kind of chlorophyll variation on an othrwise healthy Oncidium. I almost never suggest here that virus might be the issue, but there's no way to tell without doing a test.