Cattleya Dowiana - Winter Rest

[mopwr]

Hey guys, been trying out - and doing really well with - semi-hydro for a variety of plants - right now mostly cattleyas. I have a Dowiana seedling that I got with almost no roots that I actually managed to rescue with semi-hydro. It's still tiny, but grew two leads early this season and now it's starting a brand new - looking to be much larger - growth.

I know that Dowiana typically needs a winter rest, but in semi-hydro, plus growing under lights with controlled temps (82F day / 65F night), I'm not sure when that will happen. Also, with it pushing a new growth, I guess I fertilize as normal until it's done maturing?

For the "resting" phase, do I just water with pure water? Let it go a bit drier? Just looking for any experience here with managing the rest periods in semi-hydro. Thanks!

[Shadeflower]

I'm a bit confused by the question because you make it sounds like you are desperate to finish fertilizing once the new lead has finished growing.

I know lots have their theories on the matter but to me it's very simple, plants do what they want to do. You want it to flower? You want it to produce several leads, not your decision. Then some will say ah but you can influence what it does by fertilizing and that is where your question comes in to play.
See I do not believe this. I believe a plant will do what a plant will do and it will only not do so if it lacks fertilizer or is being grown wrong.
There have been endless trials to see if feeding differently during flowering will affect the outcome and the bottom line is no it doesn't. It's the overall care for several months leading up to it flowering.

So the notion to change things drastically from one day to the next doesn't make any sense to me. Maybe someone who does believe this can advise you more.

My belief is that if you fertilize strong during summer then you need to give them a few months rest or a break before you commence it all again.

Can't really advise how that works out long term. I fertilize whenever my orchids are growing, some times a bit less, sometimes a bit more.

I still have to test out if fertilzing too much can inhibit flowering which is a project for next year. Probably does but for a seedling that is of no concern as long as you are not fertilzing so strong to burn root tips.

[estación seca]

I've also wondered about growing this plant in S/H. You're correct to be concerned about watering and fertilizing a dowiana seedling in winter. Adults need to be kept very warm and mostly dry through the winter, which also means no or almost no fertilizer. I agree that with your warm conditions you should continue to water and fertilize while the new shoot is growing.

Ray has written before that for orchids growing in S/H a winter rest primarily means no fertilizer. Watering continues and the reservoir remains filled.

It would be nice to hear from members who have grown dowiana in S/H, especially unbloomed seedlings.

[mopwr]

Originally Posted by Shadeflower

I'm a bit confused by the question because you make it sounds like you are desperate to finish fertilizing once the new lead has finished growing...

So my only concern is not killing the plant. Dowiana was / is considered finicky to grow in non-s/h culture because they have a defined dry rest phase in nature and need to be kept drier and without fertilizer (according to all the sources I've read, and there's many out there). Most people who kill this plant, do so by fertilizing and / or keeping it too wet during it's resting phase... which starts rot that consumes the whole plant.

Traditional culture of this species in bark, scoria, etc., is well documented - what I've not found is what changes (if any) are needed for this rest phase when it's kept in semi-hydro. All of my other semi-hydro plants that don't have a winter rest requirement all get 25ppm nitrogen at each watering year round. I'd heard that for plants requiring a winter rest, you still water the same, but use pure water instead of adding any fertilizers. I was curious if others had experience here they can share with regards to how to manage the "rest period" or if there's any change needed at all - since I know semi hydro culture does flip a few ideas on their head.

For reference, a quote on culture of this species from Sonoma Orchids - a sentiment that is mirrored on many other sites:
"Cattleya dowiana also likes to be kept dry when it is not actively growing and the easiest way to retard its growth or kill it is to overwater it during the cool winter months when it is dormant...

Ignoring C. dowiana’s need to dry out will cause the roots to rot and eventually the pseudobulbs will decay. Unlike black rot of cattleyas, which begins on the youngest, softest growths, C. dowiana pseudobulb rot begins at the base of the oldest pseudobulb and progresses through the rhizome and kills the youngest pseudobulb last. Pseudobulb rot is always fatal, and it is the main reason virtually all of the fine old clones of C. dowiana from the turn of the century are no longer in existence...

After [it's done flowering], do not apply any fertilizer until the plant begins growing again in the spring. Never use a slow-release fertilizer because this may continue to feed during dormancy, which can contribute to pseudobulb rot."

My plant has grown all of it's roots adapted to semi-hydro (it may have had one or two tiny nubs, but it came to me essentially rootless). So the roots are used to being constantly wet. I'm assuming that the "need to dry out" is moot now, but the warning on fertilizing when not growing still feels valid... But that's purely an assumption based on reading about semi-hydro culture and how some have dealt with winter rests; I'm simply curious to hear about others successes or failures in this area.

Tangent: I also have a Cattleya Rex and if I can grow it successfully enough / big enough to one day divide, I'd like to experiment with putting one division in semi-hydro, but not until I'm sure I can manage through it's winter rest phase - as losing that plant would be devastating.

[My Green Pets]

If I were going to try one of these difficult Cattleyas in S/H, I would simply let the reservoir dry out in late October and not fill it again until new growth has started and pushed out about 3-5 cm. If I felt the plant absolutely needed water, I would perhaps mist the top of the LECA a bit with just enough water that would dry within a day. I would also be mindful to keep that dowiana temperature range of 18C/65F to 29C/85F.

[Shadeflower]

when you are the only person not receiving a like on your reply it might tell you that your opinion is not welcome.

I'm sorry to hear that mop. It is true I don't have any pure dowiana's. Plenty of dowiana hybrids but when it comes to growing Catts I did also throw the manual out the window and was pleasantly surprised they actualy grow better that way.

But maybe the dowiana which has been used for most catt hybrids since is really tricky to grow. I will carry on blissfully speculating people just like to make out it is so when they get it to flower it is even more of an accomplishement.

It must have been picked as the mother of all hybrids for a reason though.

Each to their own mop. I know it will do well either way so then all you have to ask yourself is do you need to follow the strict guidelines to a T if someone else doesn't and gets great results too.

But yes fine I do not grow a dowiana as such so my opinion is just that. Still eeven someone who has grown a dowiana seeling specifically won't have much more experience on the subject yet, not unless he has tried a) not watering and b) watering and fertilizng throughout winter and compared the results.

It's all a bit of speculation and assumptions and of course previous growers experience helps but what I found was that all the advice given was specifically for orchids grown non-hydroponically.

In hydroponics it all changes. I don't use S/H but I grow excusively in hydroponics. Or self watering pots. The traditional advice is no good anymore.

So be it.

[Jeff214]

I've been growing a couple of dowiana seedlings in bark and sphagnum moss for a few years. I've been following the no growth, no fertilizer thing. It seems to need copious amounts of water when in growth but likes to be dry and misted when in resting or in cooler temps.

The only one I killed (so far?) was the one I fertilized just when the new growth started. It may have been still waking up from its rest period? I dunno. May have been a combination of other reasons. The whole thing suddenly turned black in a few days... very sad.

[isurus79]

A friend of mine on Oahu took care of an adult dowiana when I moved from Hawaii to Texas in 2010. He was an expert grower with many decades of experience under his belt. The rainy winter with temps no lower than 60 killed the plant under his care from rot. Just goes to show how quickly this species can die with winter water over a long enough duration (remember, they still need some water in winter). I think I would follow William Green’s advice with an adult plant.

Of interest is that seedlings Cattleyas can often be pushed to grow through a dormant period by continuing to water. You might be able to make this happen with your plant, especially in the warm conditions you described.

[thefish1337]

People are growing this plant in semi-hydro:

Cattleya Dowiana var. aurea - Magnificent Orchid Species - YouTube

As long as you avoid watering with cold tap water and try to keep your night temps in the 60s at night you will be fine with your plant in semi hydro.

[Shadeflower]

I actually saw that Mygreenpets has lots of Dowiana seedlings at the moment.. He does stop watering in winter he says but also adds he doesn't know if it's the right thing to do. I don't either but I like seeing what others do.

I know this next video is unrelated to dowiana but it shows how someone can claim to have the answer yet get it so wrong at the same time.
Thoughout this video I was just thinking "noooooo" and "omg" and "is that even an orchid?" "where is the greenness?"

So don't get me wrong, I love watching nija's video's but everyone gets some things wrong at times.

I know lots will watch that video and think what's he on about, that's what I was told to do and have done also.

Did you do it in lecca though? All her plants are grown in lecca (or bareroot) and omg seeing her plants sent off warning bells for me. Those plants look in a precarious position to be entering winter and there she is saying now is the time to stop caring for them completely while the cold arrives! Well I'm not surprised she lost a lot more orchids than me this year.

She seems to have poisened her plants with copper fungicide but seriously look at the cattleya at the 8 minute mark and tell me, does that catt look healthy and able to handle temps going lower?

I'd be really surprised if that makes it with the temp drop looking so depleted as it is.

SIX TIPS when NOT to FERTILIZE your ORCHIDS and WHY | Orchid Care for Beginners & Pros - YouTube