temperature question

[mocropot]

Hi there,

Newbie question: What is the highest temperature paph can tolerate and for how long?? Is it going to affect its blooming ability?

thank you,
Helen

 

[NYEric]

Some paphs come from hot tropical jungles,depends on the species. Welcome from NYC!

 

[goldenrose]

Welcome!!! Where are you from? As Eric indicated, depends on where they're from plus humidity & light.

 

[Leo Schordje]

Actually, plant tissue is not wildly different than animal tissue. In general, if the plant tissue gets up near 105 to 110 F (40 to 43 C) the tissue will begin to die. Definite stress will begin and death sometime after.

Plants have ways to keep cool, transpiration of water can cool leaves, so the local conditions, for instance the amount of air movement, can make a big difference in whether or not a plant can survive at a given temperature.

If one is building a greenhouse, planning for cooling in summer is just as important as planning for heat in the winter. Quite a number of collections have been destroyed by a summertime power outage, where a backup generator or other system was not available.

Obviously cacti and other desert plants have adaptations that keep their tissues a bit cooler than ambient. Those bright silver white spines reflect light, as well as the bluish waxy white powder coatings many cacti have. Also in habitat, it is surprising, but often you find cacti in a spot that gets some shade part of the day.

Hope this helps

 

[mocropot]

Thank you everybody for the respond. I am in FL and a beginner. like you already know. I am trying to set up my grow area. I have an enclosed lanai and WOULD LOVE to grow there, but like I was thinking, the temperature would be a problem, based on your respond. I tried to cool off using fans, but it is only a couple degrees. It can get there really hot (100F), but usually 89-96F during the summer. I also considered an air cooler, but right now it is not an option ( money) and I am not sure how many degrees it will go down. I also tried to open the door to let the cool air from the house . Not working only 2 degrees lower. The roof is getting very hot.
Another option is inside, providing an additional humidity. My understanding is my best bet is to keep them inside during the summer time and then to move it to lanai.
What are you all thinking?

Helen

 

[Eric Muehlbauer]

I would think that for most paphs, the issue would be one of blooming, rather than survival. In other words, assuming that temps are say, in the 90's, and air movement is OK and the proper amount of water is available, the plants should survive, and maybe grow OK, but may not initiate buds. Here in NYC, heat waves occur regularly in summer. My cool growing paphs, all outdoors, including parvi's, insigne-types, complex hybrids, all make it through the summer without problems. Blooms are another story. Very rare is the paph bud that actually blooms in summer. Many buds get set in August, but don't always make it to blooming. (Actually, its the transition to indoor conditions that blast most late summer and early fall buds..they do fine as long as they can remain outdoors). I think you can still grow any type of paph. But for blooming, stick to warmer growers...but, hey...you may be able to have far more luck blooming multifloral paphs like philipinense than I ever will!

 

[SlipperFan]

Hi Mocropot -- welcome to slippertalk.

 

[Rick]

Although the temperature for absolute acute death is in a fairly tight range for the majority of species, there is a wide range of preferences based on metabolic functions that operate optimally at different temps. Species have evolved to the natural temp ranges of the environment they inhabit. Otherwise you would see much larger spatial distribution of species than you do now. Why would the "growing zones" maps be any use at all if temperature were not the primary variable in that system. There are lots of temp growing recommendations in virtually every book and catalog on orchids. These are broad categories for warm, intermediate, and cool. These are broad categories with lots of variables (such as shade levels, airflow, and humidity levels as mentioned), and you will not loose a "cool grower" overnight to a couple of days temps at 100. But a whole summer of that may be to much, and you will probably have a progressively shrinking plant over a couple of years if it survives successive summers with warm conditions.

Until you can get control of your growing conditions, I would stick to plants recommended for the "warm, or warm-intermediate" range.

 

[mocropot]

Eric, are you saying I can grow them in my lanai even the temp can raise up to 100F? I can provide a very good air movement and humidity is not a problem.
Right now I have:
Prince Edward of York
Sanderianum “ Show Shan” X Philippinense
Philippinense var Album “ Charming”
Transdoll
Angel Hair
Lowii

SlipperFan thank you for your welcome.

Helen

 

[Rick]

Eric, are you saying I can grow them in my lanai even the temp can raise up to 100F? I can provide a very good air movement and humidity is not a problem.
Right now I have:
Prince Edward of York
Sanderianum “ Show Shan” X Philippinense
Philippinense var Album “ Charming”
Transdoll
Angel Hair
Lowii

SlipperFan thank you for your welcome.

Helen

The parentage of these are primarily in the warm end of the range. 100 for peak days is no big deal to these guys as long as its 100 in the shade and not bright sunlight. With sunny exposures the leaf temps can go up 10 or more degrees above the ambient temperature. Watch for yellowing of the leaves. If they start tending towards yellow, they are too bright/warm so increase shade and airflow.

 

[mocropot]

Thank you guys for sharing your knowledge and experience. It is very helpful, but I think I did not explain my point clear enough. I am not talking about “100 for peak days” or “and you will not loose a "cool grower" overnight to a couple of days temps at 100”, I am taking about 100 almost every other day. Do you still thinking it is Ok to grow under such condition?

Thank you,
Helen

 

[Eric Muehlbauer]

I think you can get away with the plants you mentioned, even if the temps get to 100 every other day...but, what is the drop at night? If its 100 in the day, and 95 at night, that will be a problem...but if it drops 15-20 degrees routinely, those plants should be OK. Take care, Eric

 

[mocropot]

Eric, the night temp is 80 and of cause, if the day temp is lower then the night is lower accordingly. Thank you so much for your help.

Helen

 

[cnycharles]

that sounds pretty warm, but if you have lots of air movement with moist air and you can get some shade cloth or keep the light down quite a bit so that there really isn't any light rays hitting the plant (radiant head from sunlight adding to the already high temps) AND you are growing plants that require hot conditions then you should be okay. If you have moist air always blowing across the plants and it is hot, then that can help keep the plants cooler. if the plants require a good night drop and that temp needs to be in the low 70's, then you would need quite a bit of moist air blowing across to let the plant cool off. with very high temps it is very important to keep the sun to a minimum to keep the leaf temperatures from getting any higher, unless it is a required 'hot grower' again. I had for a few months a plant that was supposed to grow on top of rocks in full african sun; i'm sure that plant was a 'hot' grower! was tough but I dried it out.....

 

[NYEric]

Yes it's warm but you'll get used to it! :evil:

 

[Potterychef]

Hi Helen, I'm a bit late to this thread , but here is my two cents. I grow paphs in Houston - temps are well into the mid to high 90s through most of the summer. I keep the plants well shaded and plenty of air movement. I have found I can grow most succesfully except a few species that enjoy the cooler end of the spectrum i.e. fairreanum and tigrinum are a couple that come to mind that I have not had luck with. The multi floral species and hybrids have thrived. I also have a good temperature differential at night - which is key. This opposed to when I lived in Dallas and there can be long stretches where there is little temperature drop at night - the paphs did not like this! I currently have lots in blooms and a good number of new buds.Good luck. Doug

 

[DavidH]

Helen,

I'll add my two cents as well since I'm also late to the discussion. I've got a friend who grows paphs in Thailand. Obviously, most of the paphs are grown up in the mountains, but his nursery is down in the valley. 100 degrees is standard during the day. The key is heavy shade and high humidity. Watering during the day can help reduce temperatures in the root ball and on the leaves for a short period of time, but overall they'll be okay.

Usually (talking to a major paph grower on the west coast who's a horticulturist), paphs tend to shut off their photosynthesis around 85 degrees or slightly higher, so growth will be limited during these times but if there's heavy shade they can still absorb small amounts of sunlight.

The worst case is getting high temps with a dry environment or high sunlight without the humidity. My housesitter didn't think it important to tell me that my sunshade came off my greenhouse two weeks prior to my return from a 3 month trip. Paphs DO NOT like 5000 foot candles.

However, I am very surprised to note that roths seem to be the most light tolerant of the paph species. Although my roths were pure yellow, their leaves were not sunburned or crispy like the rest of the greenhouse and the green is slowly coming back into their leaves. So check the culture of the paphs you grow because some will be more tolerant of heat and sunlight than others.

 

[Rick]

Helen,
Paphs DO NOT like 5000 foot candles.

However, I am very surprised to note that roths seem to be the most light tolerant of the paph species. Although my roths were pure yellow, their leaves were not sunburned or crispy like the rest of the greenhouse and the green is slowly coming back into their leaves. So check the culture of the paphs you grow because some will be more tolerant of heat and sunlight than others.

My roths also like bright light, but my druryii, exul, and philipinnense take it brighter and hotter. Sometimes mine do get some time at 5000 fc, but as you also said the airflow and humidity (at least 70%) is critical.

Sometimes when people ask me about growing druryii I joke about giving them "cactus" conditions.