Yellow greenish spots on newly bought Maxillaria Tenuifolia

[iLoveOrchids101]

I received two new Maxillaria Tenuifolia orchids from Carmela yesterday. The packaging was great. But I am seeing dust like yellow greenish spots on leaves and pseudobulbs. Is that any insect damage or any fungus issue? Appreciate any help.

[estación seca]

I can't see the photos well enough on my phone. Does that rub off? Might be dried algae growing on the leaves. Carmela's is in a very wet area and Maxillarias like being very wet.

[iLoveOrchids101]

No it does not rub off. So if it is dried algae no need to worry?

[estación seca]

If it's algae you don't need to worry. But I'm not sure what it is. Get it wet and see what happens.

[estación seca]

Now that I see the photos on a large monitor, I think that is dried algae. That lets you know what this plant likes.

[iLoveOrchids101]

Thank you so much for your quick responses. I did wipe off the algae with wet paper and it came off. Sheldon also confirmed it was algae they missed to wipe off.

As you said it shows this plant likes lot of water. A newbie question. I have been watering my cattleyas, Oncidiums etc...once a week. I watered Maxillarias on two days back when I received them. They have moss in the potting medium. When I touch it, it still feels moist. So should I be waiting for that moss to feel dry and then water? Or water every 2-3 days since it likes lot of water? BTW I am growing these in house south facing window still in zone 6B.

[estación seca]

Cattleyas, Oncidiums and Maxillarias have different watering needs.

This particular Maxillaria likes being wet. Many people grow it outside in the summer in dappled shade to full sun, depending on their temperatures. They often stand the pot in a dish of water so the medium stays very wet. Most orchids don't want to be that wet.

What is the potting medium for your Cattleyas and Oncidiums?

[greyblackfish]

Originally Posted by estación seca

Cattleyas, Oncidiums and Maxillarias have different watering needs.

This particular Maxillaria likes being wet. Many people grow it outside in the summer in dappled shade to full sun, depending on their temperatures. They often stand the pot in a dish of water so the medium stays very wet. Most orchids don't want to be that wet.

What is the potting medium for your Cattleyas and Oncidiums?

I’ve got one of these doobers sitting in a clay pot with a bit of moss and mainly bark. Pretty much like how I have my hard canes dendrobiums. I’ve been reading such mixed information about this one. Some people have said they need lots of drainage and some say they even use a humidity tray. But I’ve heard the humidity tray idea is ineffective. Mine u sed to be potted in sphagnum moss for me but it didn’t show that much progress. It seems to be doing okay currently. Maybe sunlight is a factor.

[iLoveOrchids101]

Originally Posted by estación seca

Cattleyas, Oncidiums and Maxillarias have different watering needs.

This particular Maxillaria likes being wet. Many people grow it outside in the summer in dappled shade to full sun, depending on their temperatures. They often stand the pot in a dish of water so the medium stays very wet. Most orchids don't want to be that wet.

What is the potting medium for your Cattleyas and Oncidiums?

I am very new to Orchids. I have bought these orchids 2-3 months back. I have not repotted them since. Cattleyas seem to be in bark chip (as shown in photo). Oncidiums seems to be moss covered bark chips. Since I can not see under moss hard to say if those are bark chips or something else. My Phalonopsis seems to be in moss and stay wet for the longest. Therefore, I am watering Phalonopsis every two weeks.

[estación seca]

You are correct about each potting medium. All three are ready to be repotted at the next proper time. I would repot them into whatever medium you wish to use. But read on.

With the Cattleya wait until it is making new roots, and they are just one or two millimeters long. Use a pot with enough extra space for two or three new growths. Bark chips the same size as those are fine. Remove it from the pot, shake off what old bark comes easily and don't cut off roots. Don't be meticulous about removing old medium or you will damage roots. Put it into the new pot with the oldest part against the edge, and fill in your new medium. Be sure the horizontal stem, called the rhizome, is at the surface, not buried. Stake the plant so it can't wobble, or use a rhizome clip.

Oncidiums need to stay moist. It probably came from a grower in a very wet part of Hawaii, so they used large bark because it rains so often. In a home an Oncidium in large bark should be watered every day or two. Repot when new growths begin, because new roots will form soon after that. Many people use small to fine bark for these. Again, use a new pot big enough for 2-3 new growths. Shake off the old medium but do not be meticulous about removing it. You don't want to damage the fine roots any more than necessary. Repot at the same level, with the oldest part against one edge.

The Phalaenopsis is in very old, broken down moss. I would repot as soon as you can get the materials. Phals. can be repotted at any time. You could use medium to large bark, or new sphagnum moss, depending on how often you wish to repot. Use the smallest pot into which you can wind the roots. Unpot the plant, put it into a bowl of water and gently tease out the old moss. If using bark, twist the roots into the pot, and backfill with new bark. Have the bottom leaves at the bark surface.

If using moss, get it damp, then squeese out as much water as you can. Holding it in one hand, put some moss between the roots and wind them around it. Wrap more moss around the roots until you have a largish ball. Wedge it tightly into the pot. If it isn't very tight, take it out and wrap more moss around the roots. It should be so tightly potted you can pick it up by the plant and not have the pot fall off.

Water new bark every few days. Watering in moss is different. Never soak Phals. in moss. Let the top get crisp dry. Run water over the top for only one second. It will diffuse through the moss, leaving it just moist but well aerated.