Dendrobium Kingianum buds not opening, going brown

[humphret]

I have a well looked after and well established Dendrobium Kingianum I bought from a nursery 3 years ago. The problem is that there are many buds, but they never get further than the buds before they go brown and never open. One even got as far as a stem and the flower never developed.

It is in a light place and looks healthy otherwise. I water it once a week. I am not sure what I am doing wrong.

I am trying to attach photos, but having a nightmare!!

[Roberta]

First, Welcome!
I moved this post to the Beginner Discussion forum where it will get more attention.

While supposedly one needs 5 posts before attaching photos, I have seen them from newer members so I don't know if the "feature" is working. You definitely can include a link to an external storage site such as Flickr. In general, you can attach photos by clicking the Go Advanced button below the Quick Reply dialog box, then scroll down to Manage Attachments... you'll get a pop-up. Browse to your photo and select it, then click Upload and when you post, it should be there.

Can you tell us more about your growing conditions (light, growing medium, temperature)?

[humphret]

I have very good light as it grows in a conservatory. At moment, it is winter in the UK and so the temperatures at night are around 7C or 44F. It is still in the medium that I bought it in which is moss and bark. It has many new leaves, which are shiny and healthy.

[Roberta]

It is still possible to bloom this season... mine are just now starting to bloom, and I am further south - and have also had some warm days. It is hard to compare from my experience since I can grow them outdoors where I live, a very different environment. I don't give them any particular special treatment but others have suggested that they need a somewhat drier winter...

A thought... if you purchased it three years ago, and it is still in the same medium, repotting may be in order. If you are seeing new growth (which will also bring new roots) it would be a good time to do it.

[humphret]

Do you think I should repot it now? What is the best medium to use?

[Roberta]

I just use medium bark. The goal is a well-drained medium. Remember that new bark won't hold as much water as the old, so more frequent watering may be in order, especially as the plant enters its spring growing cycle. (In general, it will want to be a little drier in winter when it isn't growing much)

[humphret]

thank you for your advice!

[estación seca]

Welcome to the Orchid Board!

A tiny arthropod called thrips (thrips singular, thrips plural) can damage developing orchid flower stems. Look up photos of thrips damage. If you have that, it can be prevented by spraying the spike as it develops with a househould aerosol insecticide weekly.

I would not repot your Dendrobium until it is just beginning to form new roots.

[humphret]

How do I see the photos?

---------- Post added at 12:30 PM ---------- Previous post was at 12:29 PM ----------

I also don't have any white fur on the plant, would I be able to see tiny arthropod called thrips?

[Roberta]

Do an internet search on "thrips" to see what ES is describing.