Ideal temps for slippers

[terryros]

Forget how you would do it (or what it would cost). What would you dial in for ideal min/max temps for the major groups of Paphs and Phrags through out the year? I know they can do well in a range, but you experienced experts must have some ideal targets for growth and flower induction.

 

[SlipperFan]

I think you might need to be a little more specific. There are groups within each genus, especially Paphs, that have differing temperature ranges. I find the slipper orchid website very valuable for this information:
http://slipperorchids.info/paphdatasheets/index.html
http://slipperorchids.info/phragdatasheets/index.html

 

[SlipperKing]

I have a "mixed" collection of Paphs, Phrags, species and hybrids. With that I keep my heater set on 52*F for winter min night or day. Rarely is the day temo this low. My exhaust fans are always set at 78 and 80*F all year. It can get stuffy in the GH during the winter months so I like for the fans to clear out the GH. The max summer temp can get as high as 94*F but it's hovering a round 100 or more outside the GH.
I don't own a besseae or a kovachii but I do have some of their hybrids with mixed bloomings.
I'm in Houston, TX. Hope this helps

 

[Brian Monk]

I grow in S. Florida. For me, the temps aren't as important as the day-night temperature differential. Ideally, I would keep this at 20 degrees year round. BUt generally I get this only in the fall through late winter.

 

[Bolero]

It varies greatly. For example you can't compare micranthum to phillipinense..........you need to look at each species and hyrbid separately and see what their individual needs will be. I grow some cold and I grow some intermediate.

 

[emydura]

I guess the question is more what would be an ideal minimum temperature to keep a wide range of Paphs. My answer would be around 16oC. Not to cool for the multi's etc but not to warm that you can't grow a lot of the cooler growers. My limiting factor is the maximum temps in winter. They often don't get much warmer than the minimum temps. I think a 10oC increase would be ideal.

David

 

[Bolero]

I think 16C is way to warm for micranthum, armeniacum, hangianum, complex hybrids, delenatii, malipoense, tigrinum and others and I don't think you would get the cool temps for blooming by keeping that as a minimum. Sorry David but I disagree with you this time. Yes probably most Paphs will be okay with 16C as a minimum but it still depends on the plant.

I know you said it would be not to warm that you could grow a lot of cooler plants but I believe some plants need to be cooler than that to bloom and a number of professional and experienced growers I know believe you need the cooler temps for those plants and hybrids.

Note: That majority of my plants are grown outside all year round down to 34F and I flower them as well as anyone else I have seen.

I think the key still is to check the environment for every plant you grow and try and grow closely to those temps. Don't try and use a one size fits all approach. Grow according to your conditions and you will get the best from your plants.

 

[labskaus]

I second what David wrote. Phili has different needs from insigne. That makes growing them all on 9 squaremeters so challenging.
I wonder if absolute numbers tell us the whole thruth as well. I have the feeling that it might not be sufficient to read my Mini/Max thermometer once a day and find a min of 16°C at some stage and a max of 22°C at some stage. You may have an average temperature of 16,1°C or at 21,9° over the last 24 hours. What I'll do soon is to use temperature loggers from work and write temperature curves over 24 hours in different corners of my GH.
In the tropics, there may be a deep step down in temperature at night, but it warms up soon after sunrise. Where I live, it warms up after lunch, essentially. So, while I ultimally may reach an optimal temperature of 24°C, I won't reach it for the length of time the slippers receive it in their natural habitat. Hence, my slippers get optimal growth conditions for 6 hours a day, not 12.
The same is true for my night temps. Optimally, I would let it cool down to 16°C only for a couple of hours and not the whole night.

 

[Shiva]

If you want to grow cool and warm species, you need two zones of culture. I tried figuring out niche culture in my greenhouse and it doesn't work for the most demanding cold or warm requiring plants. Most phrags and paphs will tolerate very low temperatures in my g/h but they won't grow because of the low temperature and lower light in winter. And if I raise night and day temps, the orchids that need a cooler rest won't flower in spring. Now I keep most phrags and paphs in the house under growing lights, while everything else requiring cold is left in the g/h. And that make sense in energy cost. Having a warm room for orchids inside the house contributes to the heating of the house while keeping the g/h cold in winter helps lower the cost of heating the g/h.

 

[Bolero]

That's fine, I will just keep growing my plants successfully the way I already do.

;-)

 

[Ernie]

I grow in S. Florida. For me, the temps aren't as important as the day-night temperature differential. Ideally, I would keep this at 20 degrees year round. BUt generally I get this only in the fall through late winter.

Hey, 73 nights and 93 days is a 20 degree swing! That's about what we get in central FL in summer.

Anyway, we shoot for about a 55 F minimum winter low. One or two nights at 45 aren't detrimental to most as long as they're not wet and cold. We try to keep Barbata types warmer than 55 as well as all the multiflorals (coryos, cochlos, and pardalos). Barchys and parvis are pretty tolerant of forties and fifties as long as you let them rest a bit. Same with charlesworthii, fairrieanum, etc. For the species, there are lots of resources that will tell you their preferences. Utilize the microclimates in your grow range to make them as happy as possible. Plants raised from seed, especially hybrids, are generally more tolerant to grower extremes than jungle plants.

 

[Ernie]

That's fine, I will just keep growing my plants successfully the way I already do.

;-)

Well said. If it works, it works. All of our conditions here are different. Being slaves to our plants, we do the best we can and hope they perform. If they don't, well, we just buy more plants.

 

[terryros]

Let me make a more specific question:

For optimal growth phase (not flower induction), what would you pick as a target maximum day temperature in an indoor plant room to try and deal with a mixed collection of Paphs and Phrags?

Then, what would you target for a cooler flower induction temperature to accommodate those types that need such a thing?

We will assume at least a 10 degree F difference between night and day and appropriate variation in total plant illumination so I am only looking for your estimate of target maximum day temp for optimal growth and then flower induction.

 

[emydura]

I think 16C is way to warm for micranthum, armeniacum, hangianum, complex hybrids, delenatii, malipoense, tigrinum and others and I don't think you would get the cool temps for blooming by keeping that as a minimum. Sorry David but I disagree with you this time. Yes probably most Paphs will be okay with 16C as a minimum but it still depends on the plant.

I know you said it would be not to warm that you could grow a lot of cooler plants but I believe some plants need to be cooler than that to bloom and a number of professional and experienced growers I know believe you need the cooler temps for those plants and hybrids.

Note: That majority of my plants are grown outside all year round down to 34F and I flower them as well as anyone else I have seen.

I think the key still is to check the environment for every plant you grow and try and grow closely to those temps. Don't try and use a one size fits all approach. Grow according to your conditions and you will get the best from your plants.

I wasn't saying you could grow and flower every single Paph at that temperature. Just that you could grow a wide range of Paphs. Most of us can't afford to have a whole series of glasshouses setup for the different Paph groups. We just choose an optimum temperature and work within these boundaries. If you had your glasshouse temps set up for some of the Parvi's you included, there would be very few Paphs you could grow. At 34oF you are seriously limited to a small group of Paphs. I find you can still flower a lot of the cooler growing paphs at 16oC. Paph delanatii flowers easily for me. All the parvi hybrids flower easily. Even insigne still flowers in my glasshouse at those temps. But I can also grow warmer Paphs such as the multi-florals annd the Barbata species.

David

 

[SlipperKing]

Well, JMP(?) puts the temperture therory to shame with his basket full of armeniacum grown in a window from his house. Surely he doesn't let the temps approch freezing!

 

[Brian Monk]

Hey, 73 nights and 93 days is a 20 degree swing! That's about what we get in central FL in summer.

Yeah, but around Okeechobee we only see temps in the low 80s during summer nights. We still get the 90+ degree days, though.

 

[Rick]

Most green houses also have a range of temperatures higher and lower than what most thermometers are set at based on distance from the wet pads, amount of shade....

There are 3 components to the temperature issue:
1) the general ambient air temp, which is often fairly homogeneous in GH with lots of air flow.

2) The local plant (tissue) and pot temperature differences from evapotranspiration , which is related to humidity and air flow.

3) The local plant (tissue) temperatures due to infrared light conduction.

So even in a relatively small GH you can still manage a mixed collection of variable needs plants by varying the light levels, humidity, and airflow in different parts of the GH.

For instance put high elevation subgenera barbatas and paphiopedilum in the shadiest areas closer to the wet pad. Put lower elevation multis and paphios in sunny areas away from the wet pad.

I put some small temp probes in contact with leaf surfaces, and found that in sunny spots the plant tissue could be several degrees higher than the air temp, and in general the coolest leaf temps are right next to the wet pad in the shade (cooler than the ambient mixed air by several degrees).

I will agree that there is a lot of overlap of preferences in paphs in general (but don't expect the same with Draculas!!). And a lot of adaptation is possible (which varies by species I think).

Also the taxonomic groups have little bearing on temp preferences but look more at latitude and elevation. Within subgenera paphiopedilum you can find high elevation and latitude plants (like tigrinum, or hirsutisimum) and low elevation and latitude plants (like exul). Taxonomicaly these species are pretty close, but I doubt if most growers are getting equal success out of these species if they are sitting next to each other on the bench. My exul grows like a weed in the brightest hottest corner of my GH (where I've measured max leaf temps close to 100), while I get equally good results for hirsutisimum in the opposite corner in the shade near the wet pad (where I've measured max leaf temps at 85). The ambient air temp would be in the low 90's with the above max leaf temps.

 

[Rick]

For more examples I've killed sanderianums and supardii in the same spots that I get ideal growth out of roths, philis, and stonei. But I do have spots (shady near the wet pad), where my sanderianums and supardii thrive. All of these are Coryopetalums, and all found on Borneo for that matter, but at different elevation and exposure regimes.

Going back to general GH temps, I try to max out the summer high under 95 (I would prefer high 80's), and night lows are usually in the mid 70's during the summer. In winter I try to not let things get below 58 at night, but if its cloudy (and often is during Tennessee winters) I'm lucky to get mid 60's on cold cloudy winter days.

I used to let it dip occasionally in the low 50's and haven't really noticed that much of a flowering difference in the parvis since I've gone a bit warmer.

Leo grows lots of parvi's successfully indoors, and doesn't get near the normal lows for these species in his basement.