Cattleya with black spots

[jesleo]

Hello, I am pretty new to the orchid world and I am looking for some advice. I bought a Cattleya a couple of weeks ago. I noticed two black spots on the topside of one leaf a few days later and didn't think much of it. Yesterday I noted black spots on the top and bottom of other leaves. The black spots seem to be heavier on the bottomside of the leaves. I removed one of the leaves because it was starting to fall off. I'm thinking it's spider mites. Can anyone confirm? What is the best treatment option? Thanks

[estación seca]

Welcome to the Orchid Board!

In contrast to many other very adaptable Cattleya species and hybrids, Cattleya violacea absolutely requires high humidity and warm temperatures all year. Many people need to grow it in a terrarium for these reasons. The black spots you see can be found on Cattleyas suffering any kind of damage: Low humidity, high temperatures, scraping or crushing, sun damage, previous spider mite attack.

What are your relative humidity, and typical day/night temperatures?

[jesleo]

You are probably right about the humidity and temperature. It has been awfully dry here and we keep the house at about 68 F. I've already put it in my terrarium. I looked up what orchids were the easiest to take care of and Cattleya was one of the top orchids. I guess I should have done more research into the different species of Cattleya. Thank you so much for your help.

[estación seca]

There are people here on the Orchid Board who have shown us beautiful photos of their Cattleya violaceas. If you click Search in the top maroon menu and enter the plant name you will get a list of threads mentioning this plant.

[dounoharm]

the trick is, to keep up the humidity around the plant without impeding the drainage and drying out of the roots! this seems at odds, but what I speak of is the roots...the roots need to be firmly potted in a very large and hard bark. I see you have moss on top of your media. this is a definite no no! the base of the plant and the roots, while they require a copious watering once a week or so, must be allowed to DRAIN FREELY! no moss or restriction of drainage. I also do not like seeing the pot sit on a saucer. the bottom of the pot needs AIR! so, sit the pot on GRAVEL in a large very large saucer. while you only need to water the roots once a week maybe longer, you can put water in the gravel every couple days, but do not let it touch the bottom of the pot! this allows for drainage, and humidity! are you thoroughly confused? excellent! enjoy growing!

[SouthPark]

Originally Posted by dounoharm

I also do not like seeing the pot sit on a saucer. the bottom of the pot needs AIR! so, sit the pot on GRAVEL in a large very large saucer. while you only need to water the roots once a week maybe longer, you can put water in the gravel every couple days, but do not let it touch the bottom of the pot!

A couple of years late here. Nice recommendation you gave!

Is it ok to keep the environment humid all of the time, as long as there is some air circulation? Or could it be an issue for night time when fungus etc could start to grow?

What I've been doing for a while is to have a sand base for my planter area, with small hardware-store plastic drainage grates placed on the surface of the sand, that keeps my orchid pots away from the soil. I water the pots, and the water goes through the pots into the sand. I avoid making the sand too wet - ie. not saturated. Some kind of humidity is maintained - until the water all evaporates out from the sand. Sometimes, I spray the sand and areas between the pots with copper-spray and fungicide. I just do this occasionally - every once in a while.