Cattleya Dehydration and leaf yellowing

[kitanna05]

Hello,

I've lurked for a few months and finally worked up the nerve to post

I'm new to the orchid addic- ,I mean, hobby, and found myself originally drawn in by 2 struggling, mini phals brought home from a market. Severals phals later, I ignorantly decided to expand to a couple of Cattleyas. One "Better-Gro" Rlc Shinfong zlittle Suu Cluster Orange" from Lowes and one "Pot. Orglades Tradition Sunset" purchased and shipped from a nursery 2 months ago.

I repotted earnestly into some clear repotme pots, thinking that's what was responsible to check on roots, etc. as my previous experience with the phals involved lots of ancient moss blocks with dead roots that needed purging. The media is the same across both plants, a medium bark and charcoal mix sent to me by the nursery.

Both plants have put out new roots and seemed okay. "Sunset" had a tiny case of scale that I didn't even realize was happening on the pbulbs until I discovered a white oval on the underside of one of the leaves. I isolated and treated with isopropyl alcohol and from my observation, hasn't been seen again since. Pseudobulbs on both have always seemed on the wrinkly side, not plump.

This past week, I've watched the "Sunset" develop the yellow leaf and have been trying to search whether this is normal leaf drop or a larger problem. Scale again? Hidden scale?

Now I'm thinking my overall treatment of these babies is off, and would love some help. I'm thinking I overpotted "Sunset" (too deep of a pot?) If suggested to move or repot, can that be done safely with the roots she's put out already? Leave her alone? I've read that Catts like to dry out, so my watering was once a week for the larger and twice a week for the smaller but given that the leaves are not looking great, water more??

My stats:
-SW Ohio, growing indoor. Current room temps: Daily highs mid to upper 70s(F), sometimes just hitting 80 if outdoor temps in the upper 80s. Nightly room lows: mid 60s.
- RH: 50% average; overhead room fan on 24/7
-Grown on open Ikea glass/metal shelves with full spectrum T5 LED lights: "Sunset" does end up in closer proximity to the bulbs due to her height/pot setup but I check leaf tips for warmth and nothing.
-started using "Ray's Regimen" about a month ago: KLyte, KelpMax, etc. using the 100ppm N weekly Tx.

I'm getting a lot of "Love is a battlefield vibes" with my orchid hobby and could use some advice from others in this "battle" lol
First photos are of "Sunset" in her 6 inchx 5inch pot and cache pot

Last photos are Orange Cluster in 3x3 inch pot

[rbarata]

The plant shows signs of dehydration I suspect the roots are not in the best condition. But there are new roots so everything will be fine. It's not clear if the yellowing leaf is an old one but, considering its size, probably it isn't.
I think the pot is too large for that plant. I would repot it gently into a smaller pot, carefully to avoid damaging the new roots.

[kitanna05]

Hi Rbarata,

Thank you for your help! Outside of the new roots on both plants, the old root systems were not great which I'm sure isn't helping the dehydration problem.

The yellowing leaf on Sunset is not on what I would assume to be the oldest growth which is why I figured this was not a case of normal leaf drop due to age.

I'll have to do some careful down-sizing then to get them into more appropriately sized pots, although I think the smaller plant is in the smallest pot I have

[Roberta]

The medium looks nice and bit, so if it were my plant, I'd just let that bigger one do its thing. Those new roots are beautiful, the old pseudobulbs with bad (or no) roots can maintain the plant while the new roots develop. The leaves will wither without roots to hydrate them, and they may drop, a way for the plant to conserve water. So the old part of the plant is serving as a reserve. The new part looks great. If the one in the clear plastic pot is the little one, same thing... Ideal would have been a smaller pot but don't risk disturbing it now.

[kitanna05]

Hi Roberta,

Sorry, it is a little confusing from the pictures but both plants are in clear plastic pots, with the larger also having a cache pot in some pictures.

If I leave them in their current pots, would you suggest more frequent watering? I'm nervous to overwater given the large pots, so water the large one weekly, flushing the pot while watering the small pot twice a week, also flushing the pot.

Should I expect the roots to continue developing? They came in really strong (both new growths on the large Catt and on the single growth of the small) but have seemed to stop now or at least less obvious growth than before.

Thanks for all the help, I'm determined!

[Roberta]

Watering frequency is guided by how fast they dry out. Flushing the pot is excellent - pulls air into the root zone. The "pot weight trick" is good for Catts as well as Phals. Water well and drain, then weigh on a postal scale or kitchen scale. Do the same the next day, etc. When the rate of weight loss slows down (not much more water to evaporate) time to water again. Those new roots look great. Just let them do their thing. Any disturbance could damage root tips and cause them to stop growing, so that's my reasoning for not repotting. If that is what is going on, it is clearly the time for these to put out roots, there are likely to be more. The new roots are at the top of the medium, so I don't think there is much danger of overwatering, giving those new roots dampness (along with air) will encourage them. And be patient, orchids don't do anything fast.

[kitanna05]

Thank you very much! I'm going to bust out my kitchen scale to really get a more accurate measure of the weight as it dries.

And yes, I'm also learning that this newfound hobby is going to require me to up my patience-game too

[estación seca]

Welcome!

I agree, both are badly underwatered. I strongly recommend not repotting. This will damage the roots that just formed and make it even harder for the plants to take up water. The time to repot is when new roots nubs are just forming, less than 2-4 millimeters long.

Under a fan and directly under lights they will dry out rapidly. For that medium bark I would expect a healthy plant to be watered about every 3-4 days.

The older parts of the plant might not recover, but new growths should be fine with proper watering.

[kitanna05]

Thank you for the response! I think my fear of overwatering plus all the mainstream "Catts like dry" put me into the watering cycle I was maintaining. Also with the bottom of the larger pot holding on to that last bit of water longer... again, realizing how overpotted these poor ladies are. I had also read that cattleya's are zealous growers yet don't love repotting put me into the large pots I chose.

I've got 1 other that is just now forming root tips, not nearly as advanced as these two, so I will very carefully pot-down. Just trying to find something suitable that's more wide and shallow.

[estación seca]

It's repeated often, but I don't think it's true Catts like to dry out during the growing season, so long as they have plenty of air at the roots. A lot of growing "lore" originates from when people grew in tightly closed greenhouses with excessive humidity and temperatures often too high or too low. In such conditions Catts are less prone to rot if they dry out between watering. But on windowsills I think many people underwater.