nope, you do not need cool temps for flowers

[Mr.Fakename]

You seem very opinionated and quick to take offense.

Why not settle this argument by showing us your Phal, so we can all be amazed and start following your ways?

[SouthPark]

Maybe the best thing to do is ------ just state own beliefs, and state which beliefs we disagree with.

And just go with own belief ------ unless there are scientific groups that have carried out extensive studies on the kind of orchid(s) being discussed ....... such as a major long term study (if any) on phals of the same kind --- with controlled and significant temperature drops over a long enough period of time, and without significant temperature drops over a long enough period of time.

And even if somebody out there that wrote a book might be wrong ------ and if we disagree with their view, then we should really disagree or disprove in some nice humble way and respectful way. This is when their view actually doesn't harm or hurt orchids or anybody - unlike those people that started teaching people to use 3% hydrogen peroxide on everything (roots and all) etc.

[katsucats]

I'm not sure that a temperature reduction is not necessary to initiate blooms, but I think it's safe to say that consistent diurnal ranges (e.g. over an entire season) are probably not necessary.

[Ray]

Several years ago I tracked min and max temperatures.

Of the 365 days logged, 222 had diurnal ranges of 15degrees or more, occurring in every month. It was not until late October, however, that the 14-day running average was reduced by that much, and sure enough to, spiking started about 6 weeks later.

[jldriessnack]

Mine flower all the time, any time.

[Clawhammer]

The temperature on my windowsill changes throughout the year, especially at night.

[Dorchid]

Originally Posted by Clawhammer

The temperature on my windowsill changes throughout the year, especially at night.

This

[jldriessnack]

So then, if my phal flowers in the summer when nights are over 70 for me and day is just below 85, and in winter when everything is 10 degrees cooler, how would you explain that?

[Clawhammer]

Originally Posted by jldriessnack

So then, if my phal flowers in the summer when nights are over 70 for me and day is just below 85, and in winter when everything is 10 degrees cooler, how would you explain that?

Genetics. Some species flower in the spring/summer, some in the fall/winter

It is undeniable that a temp drop will trigger a bloom spike in most if not all phals. Growers do this en masse to prepare inventory for retail sale. It open common practice.

Is temp drop necessary in most windowsill conditions? Probably not for most complex hybrids.

These two concepts are not mutually exclusive.

[WaterWitchin]

Originally Posted by jldriessnack

So then, if my phal flowers in the summer when nights are over 70 for me and day is just below 85, and in winter when everything is 10 degrees cooler, how would you explain that?

Ummmm... A temperature drop?

Maybe I qualify for your very first explanation, where you qualify it's only about windowsill growing. I've done that, and do that with some phals. But then you try to compare your theory to everything from Asia to Borneo, which I presume means species. Which aren't hybrids.

If we compare a phal to a phal, regardless of species or hybrid, in windowsill growing most likely they will bloom somewhere along the line. Unless the temperature stays too high year 'round, or there's no diurnal curve. In a windowsill grower, there is likely a temperature change and a diurnal change as well over a year's growth.

Regardless, unless it's a species with more specific requirements, phals are tough and bloom regularly regardless of a ten to fifteen degree click of the thermometer. Because it's happening. It's why hybrids are the go-to for the common marketplace. It makes live easier for those who just want a phal around they can play with and successfully bloom.

For a beginner, who comes here and says their phal isn't blooming, the first suggestion is a 10-15F drop between day and night. Because it works. That's what commercial growers do to have tons of hybrid phals available at a certain time, regardless of the occasion.

Other than saying you think a requirement of a drop in temperature isn't necessary, in your culture and environment, making a broad statement that it doesn't matter, period, is more than a stretch. You can expound away... but I think your theory is flawed for many reasons.

Spoken by a grower, not a moderator.