Old bark mix

[rbarata]

I would even consider to put it under full sun (gradually) while keep monitoring it for sunburn signals.

[Jasonmc89]

It is pretty much in full sun most of the time!

South facing bedroom window with no shading what so ever. I have a net curtain that I put up towards the end of summer when it's getting really hot but I could leave the plant fully exposed to the sun all year?

---------- Post added at 01:47 PM ---------- Previous post was at 01:27 PM ----------

If it was a light issue would is still be growing as vigourously as it it?

It puts out about 6+ new p-bulbs a year and they all grow to a full healthy size. The leaves even have purple spots on so I thought the light was okay! That's why I mentioned the old potting mix.

If I'm honest, I think it's a combination of over fertilising and lack of light in the winter because it really does grow fast and it's getting big!

[rbarata]

Well, in that case I would think about reducing watering in late autumn/winter. In their habitat, during 4-5 month (dry season) they only get water from heavy dew. Maybe you could, instead of watering, mist only the top layers of the medium and water only if you notice that the pbulbs are shrinking.
Also, I would cut all the fertilizer during that period. The excessive growth you mention in consistent with high level of nitrogen. So you need to cut it during the rest period because it might be inhibiting the flowering.

[Sharon's Sheepdogs]

I agree with the previous posts suggesting over-fertilization is the most likely cause of the plant's failure to bloom. As previously stated, you do not need to use a bloom booster. Bloom boosters were used in the past because it was thought an increase in phosphorus helped the orchid bloom. However, it has been determined that it is not an increase in phosphorous but a decrease in nitrogen which initiates blooming.

You should begin fertilizing your orchid "weakly weekly." To do this, as was also previously suggested, reduce your orchid fertilizer to 1/4 of the amount recommended and add it to each watering instead of using a full dose once a month. Then, at least once a month, flush with clear water to remove excess fertilizer salts from the media.

When the days become shorter and the temperatures begin to cool, you should significantly reduce watering and stop all fertilizing since this species requires a dry winter rest. Water only if the pseudobulbs begin to shrivel. This will give you the drop in nitrogen you need to induce flowering when you stop fertilizing.

In the future, it is best not to combine fertilizers. When an orchid receives too much of one nutrient, it can prevent other nutrients from being absorbed. Or, it can allow a single nutrient to become absorbed in excess leading to toxicity. Always add supplements separate from your fertilizer.

It can be difficult to grow species orchids due to the specific growing conditions they require.The only other thing I can think of that might be affecting the orchid's ability to bloom would be photoperiodism. You should research this possibility. I included a link in my previous post which an experienced grower of Cattle Walkeriana provided recommendations on the conditions that need to be provided to initiate blooming. Did you have a chance to read it yet?

Finally, you really should repot your orchid if it's been three years since it was last repotted. Good luck!

[estación seca]

There is an extensive explanation here on Orchid Board. Search on the term walkeriana and the username catwalker808. I'm going to guess people are not watering them enough during warm weather and plants in England need supplemental lighting.

[katrina]

Originally Posted by estación seca

and plants in England need supplemental lighting.

Exactly! The sun is much stronger in the native habitat and a South facing window in England simply isn't enough.

If a plant is growing well but not blooming...i always look at light intensity first. And FWIW, walkeriana does not need a hard dry rest in the winter. It does better with some water but light needs to be just as intense in the winter and sun through a window in the northern hemisphere is not only not bright enough but it's also not a long enough period of time each day.

Your pbulbs look smooth so I don't think there is a problem with lack of water.

Definitely check the roots and repot if the medium is looking iffy.

[Jasonmc89]

Okay so I gently cracked the pot with a hammer and removed it today and the orchid is very, VERY root bound, but looks extremely healthy! The whole pot was full of white roots with big healthy growing tips all over the place.

I managed to remove the pot with little to no disturbance to the roots so I've sat the orchid in a pot of the same dimensions for tonight as I ran out of time.

Going to have one hell of a job removing that old bark mix though! How brutal can you be when chopping roots!?

[rbarata]

Put it in water, it will make roots more flexible.

[Jasonmc89]

Thought I'd give everyone an update.

I've got buds!!!

When I repotted, I put it in a big unglazed terracotta bowl (like 10 inches in diameter) with medium and large bark chips and it took pretty fast. Its pretty much filled the bowl with new growths already! The biggest change I've made and the one that I think enabled the orchid to bloom is that I've barely fertilised since I originally posted this thread! I stick to more of a weakly/monthly schedulal now! Growths and vigor is just as impressive as before though, so to me that shows it was receiving way more fert than it needed.

I'll attach a photo too.


Thanks for everyone's help!

[Roberta]

Congratulations - that's one happy plant!