Dendrobium "frosty dawn" help-blotchy yellow leaves

[Kdykens]

I just bought a "Frosty Dawn" Dendrobium about two weeks ago and somehow I am already killing it. It arrived via mail looking awesome-even blooming a bit. It seemed dry so I watered it, let it drain thoroughly on a paper towel, and put it on the kitchen counter. Three days later the flowers started to wilt. Then leaves at the base of two smaller stalks began to drop off. Now it's the big main stalk as well. Probably six leaves have turned a blotchy yellow with black/brown spots and died. I'm assuming it isn't a deciduous thing as they are not uniformly yellow. It is sunny in my kitchen but I have lots of shade tolerant plants in here with no problem. I would say the temp range is 67-75 degrees. Help me!!!! How did I manage to kill a healthy plant in two weeks?!?! Pic of leaves attached. Rest of plant looks healthy w full stalks and buds forming.

[estación seca]

Welcome to the Orchid Board!

Dendrobium leaves often look like that when they fall off. It is not a sign of fungus infection in the plant.

This kind of Dendrobium normally keeps its leaves for a number of years. Dendrobiums drop leaves like this when the plant doesn't get enough water, or when it is the normal time for them to drop leaves. How many times have you watered it in 2 weeks?

Shipping is sometimes hard on plants. Where do you live? It might have gotten cold during shipping.

What kind of medium is in the pot? Often commercial growers put these into very large chunks of bark. This lets them water frequently without risk of rot. Dendrobiums in this kind of medium need to be watered often, often every 1-3 days. With insufficient water they drop older leaves, and flowers don't last as long. I'm guessing this is your problem, but you need to find out what's in the pot.

If the medium is smaller and has not dried out, I would take the plant out of the pot completely and make sure the roots are healthy. They should be firm and white or medium brown, perhaps with treen tips. They should not be slimy, dark brown or black.

Photos of the whole plant, and the plant base at the top of the pot would help, too.

[Kdykens]

Thanks for your reply! I typically water everyone once a week so I've watered it three times counting yesterday. I usually do a weak fertilizer soln after watering but I haven't done that with this one since it seemed angry. I have attached pics of the whole plant and bark substrate (my fingers are in there to show scale).

Thanks!

[Kdykens]

Do not see pics so I'm trying again. Attached to this hopefully.

[Kdykens]

Pic of whole plant

[estación seca]

Maybe once a week isn't enough. This kind of Dendrobium doesn't like getting completely dry. There is a thread in the Beginners forum (see left menu, above) about using a wooden cooking skewer to check moistness in the pot.

[sara_86]

I am having the same problem with my Den. It's a Dendrobium Hsinying Frostymaree, so the "child" of frosty dawn and a dawn maree. It was shipped at the end of February and it is dropping a leaf. It was actualy behaving quite well until last week so I doubt it had any transport-related issue. However I think it dried out a bit too much last week. I dont know how long it takes for leaf-dropping thing and if a week is enough for it to sense the drying or if it relates from the change in environment but I was getting quite worried earlier.... and after reading this I am a bit reassured now! It's really good to be able to read what more senior people in the field have to say.

[sara_86]

pic attached

[estación seca]

Welcome to the Orchid Board, sara86!

Your lower leaf dropping is what happens when it gets old, or when it's not completely happy. Remember it went from a near-perfect greenhouse environment to your home, which probably isn't as good an environment as it was accustomed to.

[Regelian]

I've little to add to estacion seca's advice, other than repotting into a bark-sphagnum mix. I grow most of the Formosae species and many of the hybrids and they all like moisture with only light drying out, also in Winter. Even mounted. You will notice many are grown in coconut husk, which is excellent under the Taiwan-S.E. Asia growing conditions. Windowsill culture normally needs more moisture. Gravel trays are great and I use clay pots for all. This assures avaiable moisture, but also available air!

I wouldn't worry about the leaf(ves), this is quite typical for newly aquired plants. Do keep an eye out for bacterial spotting, due to water splash, as well as virus! I've been seeing this more often on the mass produced hybrids, such as Dawn Maree and Hysinying Frostymaree. Most plants can live and bloom with virus, but you do not want aphids spreading it through your collection. If you have not seen this infection, it looks like streaking, rather than blotching on the leaves and heavy nitrogen feeding may mask it.

Jamie V.