Black Spots & Yellow New Growth on Catt

[realoldbeachbum]

Originally Posted by Roberta

No moss... medium bark (since it is a small plant, when bigger go to large) Catts need to dry out between waterings. Perhaps Ray can advise on fungicide, I lean toward "tincture of fresh air". Fungi don't like "dry" and so letting the plant get nearly dry before watering again will do a lot to keep roots healthy and encourage new ones. (Mine grow best after they escape the pot and send roots all over the outside.) It helps to visualize the environment in which the Cattleya group evolved - branches and trunks of trees, where they get rained on and then quickly dry out. (To quote Fred Clarke of Sunset Valley Orchids, "How well drained is the side of a tree??")

Thanks, Roberta! I will stay away from spag moss when I repot. One more question please: What do you think about weak worm tea for orchids?

[Roberta]

Originally Posted by realoldbeachbum

One more question please: What do you think about weak worm tea for orchids?

This one is for Ray. He knows a lot more than I do about plant nutrition. My hesitation on that is you really don't know what (too much? too little?) you are providing in the way of nutrients. One can be much more precise with fertilizers of known Nitrogen content. Orchids don't need much at all, since they grow slowly.