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.

[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.

[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.

[K-Sci]

Originally Posted by estación seca

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

I can't address the S/H aspect, but I doubt it is different from non-S/H. My C. dowiana 4N seedlings (qty 64) have been growing continuously in bark without a rest for the last 2 years.

Edit: First year was indoors under lights with indoor conditions people find comfortable. This winter they are in my greenhouse with 75F days, 60F nights. Fertilizer year one was 1/4 tsp/gal Miracid 15-10-10 1 x month. This year it is 1/8 tsp/gal MSU at every watering.

-Keith
---------- Post added at 05:03 AM ---------- Previous post was at 04:56 AM ----------

Originally Posted by Shadeflower

I'm done exposing weak orchids to winters they cannot handle. Before I knew better I'd pop the orchid into its spot next to others that could handle it but only strong healthy orchids can and should handle a winter.

Hey Shadeflower. Could you explain what you mean by "winter" here.
Thanks in advance,

-Keith

[Shadeflower]

cold temps keith...

I grow my orchids either cold, warm or hot.

I just moved a neofinetia from the cold to a warm spot instead.

I am struggling a bit with my neo's

[K-Sci]

Originally Posted by Shadeflower

cold temps keith...

I grow my orchids either cold, warm or hot.

I just moved a neofinetia from the cold to a warm spot instead.

I am struggling a bit with my neo's

I see. What are the temperatures for your cold and warm?

Neofinetia falcata will grow and flower just fine in a very wide range of temperatures. But they're slow growing to start with and growing them cool will result in extremely slow growth.

-Keith

[Shadeflower]

temps have only been going down to like 14 lowest, I think it might have already died. Newest leaf is either black or brown. It's a bit of a mystery but then I think neo's are. Just need to figure out what they need differently, temps are the trigger but can't be the reason.

[mopwr]

Originally Posted by K-Sci

I can't address the S/H aspect, but I doubt it is different from non-S/H. My C. dowiana 4N seedlings (qty 64) have been growing continuously in bark without a rest for the last 2 years.

Edit: First year was indoors under lights with indoor conditions people find comfortable. This winter they are in my greenhouse with 75F days, 60F nights. Fertilizer year one was 1/4 tsp/gal Miracid 15-10-10 1 x month. This year it is 1/8 tsp/gal MSU at every watering.

Thanks for this, that's really interesting being as most of the material out there speaks of no rest (or improper rest) as basically a death sentence.

The only thing I've noticed with all of my orchids is that I basically try to read them in terms of what they are "telling me" so to speak... Very scientific, I know, but basically, if they are starting to grow, I slowly increase fertilizer, as they begin growing faster, increase a little more, as they slow down, decrease, etc., etc. If they stop growing altogether, then I go to the minimum fertilizer (something around 1/8 tsp per gallon sounds about right from what I do) with pure water interspersed - simply because sometimes I don't feel like mixing up more since most plants need less anyways.

An example of where I've seen that work well, is with Maxillaria Tenuifolia. Even though they are super easy to grow, I feel like they follow that example to a "T". For most of the year, they don't seem to like much fertilizer, and I've burned their roots by accident when I was still learning even though I was using fairly dilute amounts... Once they start bulbing up though, they can tolerate - even love - almost double what I give them when they're just starting out and a lot more when they are just sitting there seemingly doing nothing. Following this setup I've seen the bulbs get massive comparatively to what they had done before - this year especially, I'll know come spring if the larger / plumper bulbs correspond to more flowers, but I'm assuming so.

You raise an interesting point with just going slow and steady all the time, though. Assuming that it's dillute enough, the plant will use what it can, and there shouldn't be enough build up to cause any sort of root burn, but while it's growing less, some could possibly accumulate in the medium and sit there available for use when it starts pushing out new growths, etc. It's something interesting to think about though.

[K-Sci]

Originally Posted by mopwr

Thanks for this, that's really interesting being as most of the material out there speaks of no rest (or improper rest) as basically a death sentence.

Seedlings are nowhere near as temperamental. For mature C. dowiana wet and cool can result in stem infections that progress through the plant in a short period of time.

The only thing I've noticed with all of my orchids is that I basically try to read them

I think "reading" the plants as you described is the way to go. If it is in active growth, more fertilizer and water make sense. I have a Rhynocholaelia digbhyana and a couple C. lueddemanniana that are in active growth out of season. The watering can stays on their baskets much longer than those that are not growing. Bulb shriveling is another good indicator. In winter, if bulbs become too shriveled on a plant with good roots, increase water slightly.

...sometimes I don't feel like mixing up more since most plants need less anyways.

Sure. Why not give yourself a bit of a rest too. In the cool of winter the plants take longer to dry out as well.
-Keith

---------- Post added at 10:37 PM ---------- Previous post was at 10:32 PM ----------

Originally Posted by Roberta

I grow my Neos outdoors, so winter temps close to freezing.

Just one additional note, Amami Neos and Neos with Amami ancestry are less cold tolerant than the other small varieties.

-Keith