Dendrobium "frosty dawn" help-blotchy yellow leaves

[sara_86]

So I have received the Dendrobium in coconut and it should be repotted in May, they said. I honestly dont like this coconut potting as I can't see the roots and I dont understand if what I am doing is ok for the Den or not... I normally water it once a week by soaking it for 20 mins or so, so it doesnt get water splashes - or at least I try to be quite careful with that.

Great to find finally someone that grows these plants! Do you have any suggestions for fertiliser? I have used the orchid focus grow once, but the plant doesnt actually seem to be growing at all, could it be in the dormant phase?

Also, do these plants need drops in temperature for flowering?

Thanks for the precious advice!

[Regelian]

I use a balanced fertilizer for non-to low bark mixes, but full bark or bark-stone mixes need more nitrogen (bacteria breaking down the bark use the NO3). Always look for one with added minerals. I currently use the liquid from Schwerter, here in Germany, but any 10-10-10+ will do the job. Also, when I make my potting mix, which is about 40% bark, 40% long sphagnum and 20% other items (charcoal, perlite, gravel, which I vary for certain plants), I add a handfull of Animalin (a dried animal waste product) to about 10L of media. It helps provide trace elements.
You are water correctly, but may need to do it more often. This group of Denrobium resents long dry periods. They do go somewhat dormant in Winter, when you can cut-back, but don't let them go bone dry. I find they need a few months to catch on to our northern European weather and they often do nothing until adjusted. As with any orchid, you have to let them communicate and not force them to do something they don't want to. Most of mine are currently just starting new growths and a few are in bud or blooming. Here is a shot of D. sanderae avr. major, which has been flowering for 3 weeks, now.

J.

[sara_86]

I very much hope that my beauty will grow and bloom as wonderful as that!

Thanks so much for listening and for the tips, I'm grateful

[Kdykens]

Thanks for the help everyone! So far I have been watering much more often based on the wood stick approach and it seems a lot happier. I also moved it to a slightly less bright location. No more leaf loss as of now.

[sara_86]

Hello - I need your help again with this Dendrobium... it really is not happy, I have repotted it as it was infested with ants but because it was potted in husk I damaged the rooting system. I have now potted it in bark and sphagnum although the ant infestation has not left (I somehow think there is something that ants love about my Dendrobium...)

So it's been probably a month from the repotting and many more leaves started falling off (life 4!) and yellowing.. but now, after the yellowing they also developed black spots. Should I worry?! It really doesnt look ANY good....

[sara_86]

PS: the weather has been quite funny here recently, loads of sunlight on some days and very cold on others, I dont know how this affects the growths and hormonal systems of the plant.
Damn UK...

[estación seca]

That is how older leaves dry up and fall off. It may be their time to go, or the plant may still be adapting to your environment.

I think it should have begun new growth by now. Are there any green shoots from the base, not seen on the photo?

Is this the pot it came in? I first wrote it was larger than I would use for a Dendrobium, but now that I look at your other photos again I see it isn't as large as I first thought. This kind does like plentiful water in the growing season, but it also likes a lot of air at the roots. Too large a pot can have constantly-wet medium with inadequate aeration. Old, broken-down medium can also cause no-air zones in the pot. If you recently bought the plant and it is in old medium I would consider repotting soon - when it begins new roots. If the medium is soft and mushy I would repot right away, into the same size pot, or even one a little smaller.

[sara_86]

I have just repotted it a month ago or so, I have put sphagnum moss around the roots and a mix of bark and seramis... I am afraid this will stop some air going through but I thought it was good to keep it more moist. It had started growing a keiki on one of the canes but I took it off as I didnt want that to kill the plant. There's a tiny tiny new growth coming out of what looks like the younger cane (see pic).

I wonder if the keiki was coming up because I was fertilising it too much? I was using the "orchid focus growth" as fertiliser but stopped after repotting.

In pics also how big the plant is and the pot with the best perpective I could take..

[sara_86]

Also when I repotted the roots did look rather healthy!

[estación seca]

Don't take off new growths. The old growths get to a certain size and stop growing. They make new growths from the base that should grow to at least the size of the current growths. If you take off new growth the plant won't get bigger and won't bloom more.