C. walkeriana fma.Coerulea 'Manhattan Blue'

[Autumn Child]

This is my newest edition to my collection and I need some advice. There is some inconsistency with this plant. C.Walkeriana is supposed to be unifoliate but i see one of the seven pseudobulb is bifoliate. Is this a true walkeriana?

I was expecting the plant to arrive in bark and stones like my other catt but surprisingly it arrive in a soggy sphagnum moss covered with living green moss on the surface. It looks beautiful, but I thought C.Walkeriana needs a good drainage and slightly dryer growth condition?

Has anyone grow this strain before? I need more info and advice about this strain. Thanks.

[catwalker808]

Your flowers do appear to be C walkeriana.

Although the plant looks very healthy (but much too green and, therefore, possibly soft and prone to injury & subsequent disease), I think you're right to have concerns about the plants being in soggy sphagnum ... especially in a plastic pot. It must have taken a very discilined grower to grow in this combination, since it takes forever to dry out. In the juvenile stages, you could probably get away with growing in spagnum in plastic, because the plant & pot are still relatively small. But once a plant reaches your plant's size, I would suggest transplanting to a coarser better drained medium & pot.

C walkeriana roots need good air & drainage ... then the roots are much more forgiving. It is easier to plant in a very airy, well-drained mix and to water more often (every day or every other day when necessary). The roots need frequent moisture but do not appreciate staying soggy wet. The roots also can tolerate drought, but do not thrive in it. So you should water often. The advice about watering once every 8-10 days might hold true for a sphagnum in plastic combination, but I am watering daily these warm days & every 2-3 days when in the 70's. That's in a very well-drained coarse medium.

As for your plant having 2 leaves on one pseudobulb ... As a rule, C walkeriana is unifoliate. However, under certain conditions, I have found that some pbulbs can be bifoliate. First, is is very common for juvenile growths to be bifoliate. As the plant matures, the newer growths are generally unifoliate. Even on a mature plant, sometimes a growth may be bifoliate. But there is usually a reason for this. If a plant receives an excessive or unbalanced dosage of fertilizer, or if there is some major disruption during new shoot development, 2 leaves may sometimes result. However, subsequent growths will revert to a single leaf. In the case of your plant, the bifoliate growth may be one of the juvenile growths.

In addition, the coeruleas are different from the norm in their blooming habit. Normally, C walkeriana produces a specialized flowering growth that starts off looking like a new cane, but eventually develops into a leafless flower spike. This usually emerges from the base of the newest pbulb. However, it is not unusual for coeruleas to bloom either from there or, more often, from a flower spike that emerges from where the leaf comes out of the apex of the pbulb. I can't see in your photo, but your coerulea flower may be blooming out of the apex.

[Autumn Child]

Thanks Catwalker, I was reading up all your last post and was hoping you can reply to my thread.

Growing medium:
After reading your comment I have decided to transfer my plant to S/H. The reason being that I am afraid of the coming monsoon season in Shanghai which can bring humudity close to 100% and from last year's experience my phal in moss medium is sitting on soaking wet moss for over one month without watering. With S/H, I do not have to worry about over watering. I did tought about using bark, but it is a risk for me since I have never used bark before and it will rot quickly in Shanghai's weather (not to mention bugs that just crawled out of the plant when i repoted it). I am trying to minimize risk as this is a very expensive plant in China. I have good success rate witht he set up shown for my oncidium twinkle which grew like crazy in that set up. The water at the bottom contained a very weak fertilizing solution. I was surprised to see very good root system with active growth with very little root rot when I repoted. Do you have any comment on my set up?

Lighting:
You mentioned that the plant is alittle too green and I agree. I am inclined to relocate it to location with longer sun exposure with some direct afternoon light, but I decided to try artificial lighting to suppliment window/balcony light first. Will it be ok if I suppliment it with normal 14watt, warm glow compact fluorescence light? or is the cool day light type better? I cannot get easy access to plant growth light so I have to make do with normal light bulb.

Fertilizing:
You mentioned that abnormal fertilizing can cause bifoliate growth. I checked with the grower and he said he fertilize on the leaves once every week with 20-20-20. This is why there is annoying blue substance on the leave that i cannot get rid of. Is this recomended to grow this plant? What is the best fertilizing regime for c.walkeriana?

Flower:
The flower picture I showed is not this plant's flower. It is the picture given by the grower. The grower said that this plant have not flowered yet. Maybe its due to poor lighting.

Reading and resource:
Do you have any reading materials or website that you can recomend me regarding c.walkeriana? thanks

[Autumn Child]

My c.walkeriana is doing well in the above s/h setup. It has four new root growths and shows no sign of softening. However, I noticed that the older bulbs are more shrivelled. Only the two relatively new pseudo bulb that have not fully mature are not shrivelled. My growing condition should be ideal for this plant (temp 25-20 degree celcius, humidity 50-60%, light 2000-4000 foot candle). I checked and cannot find any root rot or other diseases/pest. Is this normal for catts in s/h?

[isurus79]

Nice looking coerulea! Congrats!

[Autumn Child]

Its been two month since i first posted pictures of my C. Walkeriana. At that time, I wasn't sure if it can survive S/H. Now the answer is clear, It is thriving in S/H with heavy fertilizing regiment. Two new pseudobulb growing and many root growth.

However, I still have question for the cattleya experts in this forum.

1) Root growth: I noticed that over half of the new roots growth is healthy, but it is "hovering" above the medium and grow as aerial roots. I have never seen so many aerial root on Cattleya. My other cattleya hybrid is Blc "triumphal coronation" grown in S/H and did not grow aerial roots. All its new roots are growing deep into the medium. My question - is this root growth normal for C. walkeriana?

2) Fertilizing regiment: SInce that my priority have shifted from making it survive to making it thrive and flower, I want to ask the expert out there about fertilizing regiment for this plant. What kind of fertilizer should I give? I am currently feeding it with balanced fertilizer half the recomended dose, but always present in the water reservoir of the S/H. I have people telling me that cattleya can thrive on just high phosphate, low nitrogen fertilizer. Is this true?

Thanks

[stefpix]

I wonder if it likes the humidity from sitting on top of humid clay pellets but also like having the root dry. Maybe it is like in the tropics. High humidity, clouds, but the roots like to dry after a rainstorm.

[Autumn Child]

That is my hyphothesis too, but i can't prove it without expert's advice. The thing is that some of the new roots actually grow downward towards the water reservoir. The reason i use s/h is also because the weather in shanghai is too hot. It gets to above 35C or above 95F right now. S/H seems to have a cooling effect on the root system.

I am trying out other method to increase airflow for my S/H.

[stefpix]

I wonder if you used a smaller pot... You couls maybe get the same effect with a clay pot filled with LECA and sitting in a saucer with water. maybe the roots would be growing outside around the pot. could be nice looking

[Izzie]

I've had great success with getting new roots to "dig down" into the media instead of being aerial- by putting a sphagnum moss toplayer on. Not to much, and not packed, but enough to make it a moister environment without causing rot.