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We all talk about heat and how plumies love it..
This is true but, a few factors that influence the plant also come into play when heat is present.
The heat I am talking about is Green House Heat either man-made or Solar Radiation trap in the Green House(GH) during warm or cool daytime temps.
When the outside temps reach 70's to lower 80's the temps in my GH reach 100+ degrees by early morning without any intake and exhaust fans running..
Can it be too hot for plumies? Yes!!!
Heat is a funny thing and more complex then most growers are aware of.
Heat can be measured with temp laser guns or other simple tools like thermometers but, this does not tell us how much heat each object has stored in the GH.
For example a cup of water and a gallon of water may be at the the same temperture, but they do not have the same amount of stored heat!
Are all your plants in your GH in the same size pot? Doubtful!
When talking about heat for our GH's, there are 3 very very important temp ranges to understand.

¤ Optimum Temp - The temperature range at which the plumie's probability to flower and to flower in the shortest amount of time is in this range.
¤ Mini Temp - The temperature at which the plumie will still flower but, at a very slow rate. If the temperature goes below this range the plumie may not flower and overall growth will slow down or stop.
¤ Max Temp - Any temperature above this range and the flowering process will abort/stop or may not occur at all. At the max temp range the flowering process is no longer at it's fastest rate but, will actually decrease thus slowing down with every increase in temp/degree. In another words if the temperature increases above the maximum the flowering process may stop and the inflo will eventually die or become a false inflo.
Example:Daisies the "Opt Temp" range is that temp that permits flowering in the fewest number of days and that temperature is 62-64 F. If you lower the temps to 50 F, the "Mini Temp" range for daisies, the number of days to flower is greater. If you increase the temperture to 80 F, the "Max Temp" range for daisies you also increase the number of days to flower.

.·:*¨¨*:·.Heat and Photosynthesis.·:*¨¨*:·.
In many botany/hydroponics books it is written the rate of photosynthesis is controlled primarily by light and carbon dioxide, but did you know heat has an effect too?
In generic terms over a specific range as temps increase the rate of photosynthesis increases if other factors are not limiting or hindering the process. The increase is linear at lower temps but the rate starts to drop off at higher temps. The effect of temperature is roughly equivalent to the effect of temps on enzyme reactions.
As a general rule the respiration rate is increased as the temperature increases. Photosynthesis is not as closely tied to temperature as is respiration but there is more photosynthesis at higher temperatures. Carbohydrates are made during the warm days but are conserved at night by lowering the temperature thus reducing the respiration rate. The logic is that on cloudy days there will be less photosynthesis than on sunny days so the cloudy day does not have to be as warm as the sunny day.
Photosynthesis is slowed down when a lot of end product builds up in the plant. That is if sugars build up from photosynthesis, the photosynthetic rate will be reduced. There is some good evidence that photosynthesis will occur more rapidly than the carbohydrates can be translocated to other parts of the plant. That means that translocation will continue to occur after photosynthesis has stopped because the sun has set. During the early part of the night, translocation will continue. Certainly by morning everything has been moved so the plant is ready to photosynthize for another day.

.·:*¨¨*:·.Heat and Respiration.·:*¨¨*:·.
The process of the controlled release and utilization of stored energy by the plant. All life needs a source of energy and respiration provides that source of energy. One of the primary factors that controls respiration is temperature. As the temperature increases the rate of respiration also increases.

.·:*¨¨*:·.Heat and the Compensation Point.·:*¨¨*:·.
In biology, the point at which there is just enough light for a plant to survive. At this point all the food produced by photosynthesis is used up by respiration. For aquatic plants, the compensation point is the depth of water at which there is just enough light to sustain life (deeper water = less light = less photosynthesis).
To be exact when it comes to plumies the Compensation Point is the point where photosynthesis equals respiration. There is a net loss of stored carbohydrates when the plumie is below the compensation point because more is being respired than is being produced by photosynthesis. Temperature is a very important factor in controlling the compensation point because of the effect of temperature on respiration.

.·:*¨¨*:·.Heat and Day/Night Temps.·:*¨¨*:·.
Thermoperiodicity - The effect on an organism of the rhythmic fluctuation of temperature, including responses associated with thermal changes accompanying the alternation of day and night.
In the business of growing roses this is the concept where the day temperture is 5-10 F above the night temps and this promotes growth. For roses that are sold by stem length this is very important!
Note:A great deal of plant growth occurs at night for plumeria's, for other plants the night temperature is very critical to crop production and frequently when the temperature requirements for a crop are mentioned it is the night temperature that is being referred to. Night temperature frequently controls the quality of the plant growth.

.·:*¨¨*:·.DNT.·:*¨¨*:·.
DNT - Difference in Temperatures.
When I say that temps affect the plumies growth I don't mean just the temperture but the "difference in temperture between day and night(DNT)" that affect stem length or node elongation. So to put it in numbers a DNT is calculated by subtracting the night from the day temps.Using this simple formula if the day temp is higher than the night temp you have a positive DNT. When the night is higher then you have a negative DNT.

Example: If the night temp is 65 degrees and the daytime temp is 75 degrees then the DNT is a positive 10 DNT because 75 - 65 = 10

One more thing to consider also is the amount of difference between the night and day temperature is important. A positive DNT of 6 will not give as much elongation as a positive DNT of 15.DNT will affect other factors in addition to the plumie height. Seedlings grown in a negative DNT environment are much shorter than if grown under a positive DNT but they are also chlorotic. The leaf yellowing seems to be related to the negative DNT. If the seedlings are taken from the negative DNT environment and moved to a positive DNT environment, the leaves will turn normal green. As a general rule it would not be recommended to grow seedlings under a negative DNT environment. A zero DNT environment would provide an environment where the seedling would not stretch or become too tall and would stay green. The leaf orientation of some plants is affected by the DNT environment. The classic case is the Easter lily. When lilies are grown in a positive DNT environment, the leaf tips point up. When grown under a zero DNT environment the leaves tend to be horizontal. When grown under a negative environment the leaves tend to point down and look as if the plants are wilted. If the leaves have not matured, the orientation can be changed by changing the DNT environment. Once the leaves have matured, then the leaves will stay at the orientation under which they matured. It is also important to note that the DNT response is very rapid. For example changing a lily from a positive to a negative DNT would show up on the plants height and leaf orientation in 1 or 2 days.
When the night temp is higher than the day temp then photosynthesis would be slightly reduced because the day temp is a little lower. Since the night temp is higher the respiration rate is increased.Plants that are grown under conditions of incandescent lighting (low RFR) produce plants that are taller than those that are grown under fluorescent light (high RFR).A light source that has a low RFR like an incandescent light can over come the effect of a negative DNT.It is known that light affects the pigment phytochrome in plumies.
http://en.wikipedia.org/wiki/Phytochrome
Phytochrome is the receptor either red or far-red light. If plants are lighted with night break photoperiodic lighting at night, the plants tend to be taller (hence some of my seedling pictures) than if those plants had been lighted with fluorecent lights. So it appears that a light with a low RFR will promote stem elongation in plumies and other plants.The physiological basis of DNT is believed to be related to the internal gibberellin levels of the plumie and other plants. GA(gibberellic acid)can over come the effect of a negative DNT environment. For example if plumie seeds or cuttings were soaked in GA then grown in a negative DNT environment the plumies were as tall as those that were not grown in a positive DNT environment.
Not only does the amount of DNT affect node elongation, but so does when the DNT is applied. The shortest plants are where the negative DNT can be maintained all day, but if the negative DNT can not be maintained all day because of the warm sunny weather in the spring, keep the morning cool. The plants will almost be as short if the temperature is dropped at sunrise and remains low for 2 to 3 hours. Just the short temperature drop early in the morning will prevent a great deal of elongation. This technique is particularly important for bedding and spring flowering plants because it is not possible to keep the temperature low for the whole day.

If you want short plumies:
1. Keep day temps as close as possible to night temps.
2. If crop is delayed increase day and night temp so that average temperature is higher.
3. If day temps can't be controlled for the entire day, drop temps just at sunrise and this will help to keep plants short.

If you want tall plumies:
1. Have day temps 10-20 F higher than night temps.

.·:*¨¨*:·.Soil & Plant Age Temps.·:*¨¨*:·.
It seems that the optimum temperature changes with plant age. As plants get older the optimum temperture decreases. The normal sequence of events would be for the crop, when it is young, to start out at a relatively warm tempertures. This temperature would be maintained throughout the early vegetative growth and perhaps the begining of the reproductive stage. As the crop is begining to flower the temperature would be lowered. When the crop was in full flower, the temperture could be lowered again.
Maintaining warm soil temps generally will result in increased growth. If the soil is not heated and there is a low soil temperature, water and nutrient uptake is restricted and it is possible to see nutrient deficiencies. These deficiencies are actually induced by the cool soil temps. If the soil is not heated directly, then the soil temp is controlled by several factors. Air temperature will have a very large influence on soil temperature. Solar radiation will also affect soil temperature depending on how much of the soil is exposed to the sun. The temperature of the irrigation water will influence the soil temperature at least for a period of time. If the soil is heated, the location of the heating coils will affect the soil temperature as well as the distribution or uniformity of the heat. Generally there is an optimum temperature for roots. For roses, for example, the top growth increased as the root temps went from 56 to 64. Above 64 the top growth decreassed. In general warm roots are beneficial for young plants and cool roots are beneficial for mature plants.

~Lopaka~

Robert, I just want to thank you so much for posting this. The next time that I update the FAQ's Sticky Thread, I will include this link so it can be referred to easily. I've only a few minutes here this morning so I don't have time to read it as carefully as I want to so I will be back later tonight to read it and will comment on it. Thanks again for posting this.

I want to thank you too. Just have a little plumie collection, but my experience seems to be consistent with facts you have explained here. My seedlings seem to thrive when I sit them in the driveway, full sun. The older ones like the shade relief provided by my patio eave.

Very interesting thread, Robert. My greenhouse temps are around 110 with the front door open during the day, and at night, temps are in the mid-50's. So I guess I have a positive 55-60 DNT;-) I have yet to find a max temp for my greenhouse plumies, but the humidity is high, and the plants are very well-watered. I have so many inflo's forming that it should be an exciting year.

I am thinking about keeping one or more of the greenhouses up for the summer. Summer daytime temps will be around 130 in the greenhouse with it open. I can probably open it further by creating some cross ventilation and opening the rear door as well. I have a friend who has the same greenhouse that I had for two years -- the one from Harbor Freight Tools -- and she left hers up throughout the summer last summer and found that she had so many more inflo's than she had ever had so I thought I would follow suit with one and see what happens.

I do know that some people in Australia experience a maximum heat temp, but they have water and rain limitations, at least in certain areas, so lack of irrigation plus might be adding to the slowing down or stopping of blooms in that case. Gordon visited Costa Rica and found plumerias thriving in areas of extreme high heat, and his own rooftop measures 145F, I believe he said. Of course, this is not man-made greenhouse heat as your article refers specifically to.

I do wonder about genetics when attempting to control or manipulate growth rate and growth habit. If a certain variety is known to be a tall-grower, for example, can it really be manipulated to be a short grower using temperature? Thanks again for posting this food for thought.

Glad you like it..
Clare does the same plumie that grows tall continue to grow in winter when they are dormant?
I say no because Photosynthesis has slow down so if heat can control Photosynthesis then it can control
that tall plumie.
In my post GA3 nulls and voids all this just like other products i use from time to time..
Plumies are Phototropic:
http://en.wikipedia.org/wiki/Phototropism
So we as growers can control their growth height by controlling the amount of light they get...
Plumies will always reach for the nearest light source so if your light source seems bright to you it may not be
bright enough to the plumie so it will reach for it as fast as possible and become tall and lean in the process!
Since heat dictacts how those plumies use this energy they are gathering then it is important to keep them warm when they get this light..

Basically i see plumies like my solar lights in my walkway..
The leaves are like solar panels and the rest of the plant are its batteries which store the energy it gets..
On a cloudy day the lights don't stay on very long or are very dim..
So plumies on a cloudy don't get the energy they normally get on a clear day so what happens is the plumie is using up more energy then it is getting and Photosynthesis comes to a halt no matter what the temps are.
:0

This is a very interesting thread, thanks for posting, Lopaka.

I have never heard the term "DNT." I have always known DNT as "DIF." I wrote a thread on DIF and internodal stretch on the GH forum last year, but it generated little interest. :-( http://davesgarden.com/forums/t/573322/

Practically speaking, negative DIF/DNT is difficult or impossible for most of us to attain. My understanding is that negative DIF/DNT is mostly a reasearch tool.

A couple of questions...

So what are the Opti temp, Min temp, and Max temp for Plumerias?

And what are the optimal soil temps for mature Plumerias? I am familiar with the "absolute zero" soil temp of 54*F for citrus...the temp below which no uptake of water or nutrients will occur...do Plumeria have an "absolute zero" soil temp?

Thanks,
SB (owner of just four rooted cuttings, now actively growing in the GH!)

Thanks, Robert. You are quite right that there is no growth during dormancy for the ones that are outside the greenhouse. The ones inside do grow but perhaps at a slightly slower rate than the summer. New branches form around the inflo's as they bloom and develop, and the progressing of inflo's and blooming continues during the winter. I added a grow light to one of the greenhouses for a short while, but it broke, and I didn't replace it. I was surprised to see so many plumerias blooming in the greenhouse without it.

I agree with SB about negative DNT. It was interesting information but not practical for most of us as there are few, if any, areas with nighttime temps which are warmer than daytime temps. It would take a lot of electricity, heat, and temperature control, I would think, in a greenhouse to create warmer nights than warmer days. The information about warm soil is gold, and I'm glad you included that in your article.

SB, I will read your thread tonight. Thanks for posting it.

my plumeria continued to "grow" while in the gh during summer. they did not push out any leaves. however, the diameter of the branches near the tips expanded (see pic). they show evidence of photosynthesis throughout winter.

clare - i will be leaving my gh up during the summer, too. we'll have to compare notes. the humidity in my gh is stays above 75% when i don't vent it. i will have a misting system in there this summer since it will be too hot to leave it closed. let's compare notes.

dete

Welcome Clare..
Thanks stressbaby for the link..

Negative DNF or DIF can be achieve with no problems i done it many times...
All i have to do is open up a window and let the house cool it off because of my design of the GH..
I only did it to see if the there is a difference..
The nurseries down here publish many such tests and DNF as they called it are also published but i believe they call it DIF also..
The DIF or DNF whichever is the correct name is nothing new to Florida nurseries and the reasons for the test is to save energy in the greenhouse and control crops/flowering..
This doesn't applied to the little guys so much as to the large farmers who run the spilt times at night to save energy..
I also run the brix test and check the sugar levels..
As far as the negative tests is concern..
You are both right and as i publish this post i was going to leave it out but because i took research data and applied it to plumies i added it so peeps here would see the whole picture..

=============================================
To answer your question stressbaby..
The plumeria is very different then many plants and it seems no 2 are alike when it comes to the DIF/DNF or Brix tests..
I could give you numbers on the plants i tested but they may be wrong with your varieties..
The brix test drives me crazy as i been trying to come up with a general number for the sugar levels..
Example:
The Magnum Opus has a Brix level of 15 in full bloom while a nassau is 10 in full bloom.
The DIF/DNF results for me are as follows:
I run a positve 25 based on day temps @ 100 degrees and night temps @ 75 degrees.
All my plumeria's are not only growing fast but have hugh healthy leaves and not just blooms..
http://farm1.static.flickr.com/151/392771174_1c61af4e73_o.jpg
http://farm1.static.flickr.com/158/392771254_6184556a67_o.jpg
Having alot of blooms is nice but if you do not have the full set of leaves to go with it you are robbing yourself
the full color spectrum of what the flowers should be and you don't get the pungent fragrance from the varieties that should smell..
The leaves carry the sugar that is tranported to the flowers and this is what gives you the larger and more robust flowers that are seen in many pics..
Plumies will bloom in low light conditions/winter because it is their will to survive and the only way to do this is to drop all their leaves so no transpiring will occur which equals to no more energy loss and thus all her saved energy goes to flowering which is nature's way of creating offspring to carry on..

As far as i know i am the only one that is running Brix or DIF/DNF test on plumies so i have no baseline to go by but i am force to create one as i go along..
This is a daunting task and i could never do it alone, because of time and because of all the varieties out there...

Thanks again for the link and thanks Clare for the feedback.


This message was edited Mar 25, 2007 2:18 PM

Thanks Dete sorry you posted while i was editing my post..
Yes photosynthesis does occur thru the stem walls it is the plumies way of storing energy..
I see the stretch marks from the cells expanding within her..
Please both of you compare your notes on the forum so we may all see the results..
BTW
Hows the weather Dete over there??

Thanks, Lopaka.

Here is the link from my thread, the best discussion of DIF/DNT I have found: http://www.for.gov.bc.ca/nursery/fnabc/Proceedings/TempAndIntegratedControl.htm

SB

hi robert,

the weather is starting to get cooler here. actually, it's returning to seasonable norms. night are heading toward the low 40s. brrrr... of course, now all of the plants will freak out. oh well, what can you do. the plumeria in the gh are having fun! only one new inflo. i thought there would be more. sheesh! sometimes i just wanna reduce my collection to one - aztec gold. waiting to see what comes back from the ground that was damaged in the freeze. other than that just anxiously awaiting the 100+ degree summer weather. haha!

Ouch Dete that stinks..
My hats off to you for really being dedicated to grow these wonderful plants in those adverse conditions..

Dete and Robert, yes, we will compare notes about our plumies in our greenhouses this summer. Dete, your sprinkler system sounds neat.

Robert, thanks for including all the information for us to read and learn from. You put in a lot of work here, and your dedication to these plants is undeniable. You are greatly appreciated for your friendship and for the information that you freely share.

hi clare,

right now it's 97.5 degrees and 80% humidity in the gh. the humidity drops drastically once i vent the gh. that's when i will run into trouble because now the plants will have dry air around them. the misting system will actually help to not only keep the humidity up but also lower the temp. i'm not sure by how much at this time.

not all the plumeria will stay in the gh during the summer. i don't have enough space. i have to pick and choose which ones get cast outside into the harsh heat and dry air. bummer! LOL

i look forward to seeing your results. i think i will have to buy another hygrometer to be placed outside of the gh.

dete

Dete, I just opened mine up as the sun just came out. It was overcast until now. It's 102.9 in there now. I don't know what the humidity is, but it seems high. The humidity drops when I vent them too, but keeping the soil constantly moist helps. I bet your plumerias will thrive being misted. Can you set up a misting system in your yard too? I think I want to put some seedlings in mine. Maybe that will help them to bloom sooner. We are still having temps in the low 40's at night on occasion here. Many of my plumies outside still have no leaves, but some are sending up inflo's. I look forward to your results also.

clare - i just opened mine, too. LOL i want to see how fast the humidity drops. i guess i should figure out what is acceptable.

robert - what are your summers like in terms of humidity and temp?

dete

Clare thank you for your kind words nothing puts a smile on my face when others learn from my mistakes..
The more growers that learn from all of us in here the more peeps WILL BUY PLUMIES! [hear that sellers!]
Of course for me it is personal as i am not a seller but if more peeps grow plumies the more new varieties will get born!
:)

Dete summers are scorchy to say the least..
Average temps are in the 90's with the humidity in the upper 80's to 90's.
When the temps and humidity are near each other the flowers will display radical colors and the smell of them will increase big time..

Dete since you are in a dry place may i suggest something?
First lay rocks down on the floor then..
Lay wood in the GH like 2x4 or bigger on the floor make sure it is pressure treated at least..
Use a plastic covering inside if possible and..
Setup a small sprinkler system to divert the water on the floor only and not the plants..
The wood will hold the water longer and generate more humidity inside..
I have a wooden pool deck as my floor and just 2 mins of spraying the floor with my hose my humidity in winter went from 32% to 85% in 5 mins and stay that way for a very long time and slowly slowly bled down to 50% overnight!
Wood (fir bark) is what all the reptile owners use to lay down in their cages down here because wood/fir bark generates heat and humidity..
Why do you think it is in all the orchid mixes?
:)

This message was edited Mar 25, 2007 11:37 PM

Lopaka, are those numbers from inside the greenhouse? Because as outdoor climate numbers they don't make any sense.

An average temp of 90 with RH of 90% gives a dew point temp of 87F. This is way higher than the average August dew point temp for Key West (highest average in the continental US) of 75F.

SB

Good recommendation there, Robert. I heard pumice increases humidity too.

SB, yes, I believe Robert was referring to greenhouse growing when he mentioned those numbers.

lopaka-I read your post with interest-thanks! The thing that caught my eye was that you said that it was so easy to attain a negative DIF in your grhouse just by opening a window and I wondered if you could elaborate? Opening a window at night or during the day? How big is your grhouse? I am not familiar with the average nighttime temps in your area, or whether you use a heater in the dead of the winter, but I know that here in zone 7b, the only way that I could ever achieve a neg DIF is in the dead of the winter on a cold. cloudy day, where I shut the heater off and let the temps go down below 60 degrees ( which it would do-but not by much). It would be a very hit or miss situation. Any day that there is sun, forget it-the fan comes on by 10 am-in the winter. In the spring and early summer sometimes the fan comes on by 8:30 am. I set the thermostat for the heater at 60 at night and 75 during the day, and that is about as close as I can get the two temps.

SB yes i meant outdoor temps not GH..
That is South Florida for ya..
Key West is a Island and is always cooler then us..
In fact Ft Lauderdale (davie) always post the hottest temps in florida..
It seems no matter what time of the year it is, the temps and humidity seem close to each other..
I just took this snapshot @ 3:00am on a weather site..
http://img92.imageshack.us/img92/2117/snapshotxp9.gif

Tiger here is a snapshot of my GH:
http://farm1.static.flickr.com/164/353641745_e2556dab5c_o.jpg
I have 2 windows inside of it that are attach to my house..
I just have to open both and the ac cools my gh bigtime..
At night all i have to do is close them and the temps are in the upper 70's low 80's without any heat from me but i can heat it up real quick at night with my propane heaters..

Lopaka, I'll wager you a Plumeria that "temps are in the 90's with the humidity in the upper 80's to 90's" are the very rare exception, rather than the rule. ;-)

At 90F and 90% humidity the air holds so much water vapor that when it cools at night, all that water vapor condenses and comes right back out of the air.

At 93F, 90% RH, you have a dew point temp of 90F. This is the highest dew point temp that have ever occured in the US, and then only a handful of times (in Florida and Louisiana).

Southern Florida (not Key West) has average dew point temps in August of 74F. At 90F this translates to a RH of 60%. At 95F this translates to a RH of 51%.

SB

SB save your plumies i don't need them but may i suggest you give one to someone here who could use more in their collection..
:)

Last year we went from winter to summer with no spring..
In this post alone it is title "Rain Rain go away blah blah.."
If you read this post i talk about it raining for weeks non-stop that i don't have too many blooms..
Anyways i am busy at the moment off to work but just a quick search on the history of zipcode 33314
which is shared by Hollywood,Davie,and Ft Lauderdale tells you everything you want to know..
Scroll down to the bottom of page to "Observations" and look at the High Temps and the High Humidity readings..
Here is April thru Sept of last year also look all the way to the right and see how much it did RAIN!
http://www.wunderground.com/history/airport/KHWO/2006/4/1/CustomHistory.html?dayend=31&monthend=9&yearend=2006&req_city=NA&req_state=NA&req_statename=NA

I have a question do you live here or ever lived here??
Heat and Humidity is the norm down here and those charts are the actual readings..
Lol i never had to prove to someone about South Florida humidity and heat factors..
;=)
One more note..
They said on the news today that South Florida weather is going to be hotter and the winters are going to be warmer as the years go by and now they want to move South Florida to Zone 11.
Let me know SB if you need more info it is not a problem i am just busy working and post when i can..
Cya!

This message was edited Mar 27, 2007 5:12 PM

OK, maybe we're talking apples and oranges here. :P

I'll agree that in a given 24 hour period you may often have 90F and 90% RH. But my point is that they don't happen at the same time.

The point during the day when you hit the high temp is not the same point when the highest humidity is recorded. Your link shows this quite nicely! Look at 8/7/06. Maximum dew point temp was 79F, very uncomfortable. The high temp was 91F. The highest RH during the day was 85%. But this could not have occured when it was 91F, because at 91F, with a dew point temp peaking a 79F, the RH is only 68%. How about the previous day, 8/6/06: the high temp was 91F, maximum dew point temp of 76F. On this day the RH at the time the temp peaked was no higher than 61%. The 94% maximum humidity recorded on the chart occured late at night or early in the morning, I suspect.

Now, I expect nobody will believe me on this, because I'm from Missouri and I don't live in Florida. However, some years ago I mentioned that we occasionally had a 90F/90% day here in Missouri. I was corrected on this from a chap in Australia! I researched it diligently in an unsuccessful effort to prove my point. Oh well, I learned something!

So, Lopaka, you have plenty of Plumerias...OK, then show me where more than a couple of times a year you have 90F/90%RH at the same time, and I'll send you a nice Cyrtostachys renda. :-)

SB (also a Robert)

Thanks, Robert and Robert, for this interesting discussion, which is way over my little head! LOL! But, please, don't explain it to me. Ignorance is bliss sometimes:-)

Actually, someday, when I have to move out of this lovely warm paradise to the frozen tundra of Colorado, I'll need more advice about greenhouse growing, and I know where to find it.

lopaka-I have been laughing at myself all day after seeing your grhouse! Ever since I read where you said that you could easily achieve a neg DIF, I was wracking my brain to figure how-and as well, why. It never occurred to me that you had your grhouse attached to your house! Now I get the "window" . I was referring to a grhouse that was out in full sun all day-away from a house or trees ( as mine are), and most commercial grhouses are. Here is a picture of one of mine, and I think you can see how hard it would be to attain a neg DIF. This grhouse is 100' long, but in the picture it looks shorter, doesn't it? Don't know why that is-a photographer I am not! lol
Thats Buddy, the cat-he loves to lay in the flats when I work!

..takes a deep breath
SB you are missing my whole point here and you are stuck on the numbers too much that you failed to consider other things!
It would help you to read my post "Chill Out" to see what i am talking about..
Lend me your ear for a minute..
When it comes to RH we all know @ 100% the dew point is equal to the temp..
Ok this is fine and dandy for classroom stuff but let's just say the humdity is in the 80's and 90's as it is almost every morning in the summer time down here..
The temps in the morning in the summer time down here range from the 80's to the 90's alot..
For the sake of pounding a dead horse lets say the temp is 82-85 degrees @ 10:00am and the humidity is 75% to 80%.
Given these reasonable numbers you as a grower walk thru your garden water your wonderful plumie collection that most likely are in black plastic nursery pots and most likely those same pots are either on concrete or the typical black nursery weed blocker film..
Now you as the grower had just watered your plumies or a rain shower blew thru 30 mins ago and your out checking your plumies to make sure all is ok..
I don't want to bore anyone but what are the typical conditions of most growers in Hot and Humid places like Florida and other places??
NOT what is reported on any weather site i assure you that!
This all boils down to microclimates and the typical nursery conditions or the normal backyard grower conditions..
Black Nusery pots generate and hold alot of heat, much more then the ambient temps reported and what about the black weed blocker on the ground and take it one step more like what i use and that is Silver Mulch and Mylar.
Since it is the morning many nurseries and backyard growers water their plants..
What did i do to the humidity levels in my garden?
With morning temps in the 80's do you think the plumie feels that when her feet are soaking in 100+ degrees of recycle plastic?
The weed blocker and Silver Mulch hold and reflect Solar Radiation back up to the plumies underside all day long and even thru the night..
If it just rain, like it does alot in summer or when i water my plants in the morning what did i do to the ground surrounding my plants and even the soil in the hot pots?
This is what i mean by my statement,this is what we have to go by as growers because this is what the plumie feels and not what is reported by weaver the weatherman!
I see your point and it is valid one, but like you said it's apples and oranges..
Can we move on to something else?
;=)

Tiger lol sorry about that but i am used to just posting and assuming everyone has read past posts..
Very nice GH you have there and kool cat..
I wish i had one that size for sure lol i think Brad has a big one too..
To tell you the truth i would rather have the 100 feet of more yard then the GH..
;)

Terry, that is such a cool greenhouse! I love it! My cat 'Buddy' kind of looks like your cat 'Buddy'!

Here he is being a jungle cat!

Thanks Clare-your Buddy is beautiful-I love the brown in him. My Buddy loves to go in the grhouse when I am there, he loves to run down the middle top shelf and follow you as you walk down the aisle, but now that all the grhouses are so full, he doesn't have the freedom to follow and you can hear him down the grhouse meowing away like he is mad! He scares the workers when they are bent over working and he jumps on their backs to lay down on them! Everyone loves Buddy. My dogs come in the grhouse too. I have one dog that lays in front of the heater when it is on-its a big heater and a lot of hot air in Bear's face but he loves it. Here is Bear and Bill

Well, I just love Buddy, Bear, and Bill! Great names too! You've got a great family there. That is hilarious that your Buddy jumps on people's backs and wants to hang out there. I just love it when my kids, as I call them, follow me around the garden. My Duchess died a couple of years ago, but Duke still wants to be with me, when I'm outside, even though he can't get around like he used to anymore.

Here is Duchess with the plumerias:-) I still miss her so.

Well-he is a handsome guy! You are right-they just want to be where you are-all the time. Except at noon, when they eat again. You can set your watch by when they get up and go to the door! It is amazing how they know when it is time, and you are still outside working. lol

She looks like she had Great Dane in her? I love big dogs myself. There is not much harder to bear than when you lose a pet-esp if they are family-as ours are. It usually takes me about 3 yrs to get over the death of one before I can replace them. Thats why I keep one younger and one older.

Thanks, Terry. You are so right that they surely know the time of day! Duke is a handsome guy, isn't he? He is an old man now and needs help getting up every time he lays down so that is my job all day long, but I don't mind. Anything he wants, he gets. My pets are family too. Duke is 13 now and even bigger than Duchess was. Duke is about 150 pounds and is on a diet. Duchess was indeed a Blue Merle Great Dane and an angel sent from heaven. She died at nine years old in January, 2005, so I see that I have at least another year of mourning. That sounds about right. We haven't replaced her with another dog because Duke is so jealous of other dogs when they come around me and so protective, and he is so old that we feel he would have a hard time adjusting. When he goes, we will adopt two more, I'm sure. I cannot see my life without dogs and cats in it. Their company is one of my greatest joys in life. I love the big dogs too, but it is cruel that their lives are often shorter because of their size.

Edited to add: Sorry, Robert, that I changed the subject of your original thread!

This message was edited Mar 28, 2007 2:02 PM

Clare and tiger wonderful pets you have.. i love it!
Clare never say sorry to me i don't mind if anyone joins in any of my threads..
I do this for the love and to help others if anyone here wants to use any of my threads to say hi to each other or just post pics i am honor that they did..

I just want the thread to keep moving and i like when peeps like SB bring up valid points but i want to make sure we don't bore anyone at the same time..
:=)

Keep posting peeps i really enjoy reading them when i get off work..
It's getting busy for me with work and all the plumies coming in from thailand as of late but i will keep making time for daves..
In fact i am going to grab some peeps from other places and tell them to get their arse's over here..

BTW
More seeds went out today!!!
5 more peeps will be getting them soon..

Thanks, Robert! Don't work too hard!

Wow, you all have great looking cats! I have to type here with mine on my lap or she gets mad. I don't think wood is a good idea to put on the ground here in Arizona, We have termites. Last year I discovered they were eating a table my husband had made for me for the green house. A far smaller one than what you all have I must say. For the last month my poor husband has been rebuilding our one deck because the termites were chewing on it.
Mickey

Mickey...
That is why i say pressure treated wood which has rat poison in it that kills termites..
Boric acid powder mix with water is the perfect termite killer..
If you spray it on the wood not only will it preserve the wood but will kill any termite and most bugs that comes in contact with it..
Boric Acid is oderless and this is why it kills many bugs..
Florida is one of the worst places for termites,we have some that eat thru concrete and steel so if they are not issue for me then you should be ok..
Remember termites like wet wood so if you live in a dry area and have wet wood laying around or even wet rocks, or wet mulch then you will attract them..

Get yourself some "BoraCare" awesome stuff!!
http://www.doyourownpestcontrol.com/spec/pick-boracare1.htm
DON"T GET IT ON YOUR PLANTS!!!!


This message was edited Mar 30, 2007 6:25 AM