Nick,
Congratulations on your better-than-usual conditions!

Given the three factors that you presented, increased sunlight this year should be at the top of your list. Do you have access to comparative data re: light levels from 2008 to other years?

--Stitz--

Probably a combination of all three. I agree with Stitz that the increased light is probably the biggest contributer.

I water my mounted Cattleya types once a day when the temps are in the 90s and mostly twice a day when they are in the 100s. Of course, the humidity has a lot to do with frequency as well. They will get watered more when it is in the 20-30% range than in the 50-60% range.

I thought that might be it. While the rest of the Northern Hemisphere basks in glorious Spring conditions, we in SOCAL are definitely second class citizens. Anywhere near the coast, May and June usually feature a thick, dripping fog which totally obscures sunlight until it burns off. Sunlight may not be more than 5 or 6 hours from 11AM until the fog rolls in again 4PM. This condition disappears by 4th of July out of respect for the holiday.

Since the same plants bloom and grow at the same time every year, the May and June growers could well have been stimulated by the optimal conditions this year. Or by my increased watering!

There is a grower in Los Osos, Los Osos Orchids or another grower with a similar name in the same area, which was reputed to have a Vanda room were automated sprayers, one for each plant, sprayed every plant 5 seconds every 30 minutes. The idea is water, then water again when the roots are dry. My idea of watering as often as 5 times a day on really hot days relies on the same principle but I really don't know if its the changed climate or my increased watering. I kept and still keep the total amount of fertilizer per week constant.

Nick

Nick,

Some of my orchids that are planted bareroot (phalaenopsis, cattleyas and some dendrobiums) are watered like my bareroot vandas: 5-6 times a day in my tropical climate during the dry season (no rain). (Tropical climates only have two seasons:
wet and dry).

My bareroot orchids especially my vandas love the frequent watering probably because it reminds them of home--- the tropical rainforest where it rains several times a day, 365 days a year... No potting medium whatsover that will make their roots rot in this high rainfall/high moisture environment.

I wouldn't recommend however such frequent watering for orchids planted with some medium on their roots. It is the surest and fastest way to kill them. I know. I've killed lots of my dendrobiums this way.

tropical

I tend to agree with you, tropical, I stated in my post that it only applies to bare root plants and I mean just that, absolutely no medium whatsoever. In the past I have not watered this often but this year I did. Other factors have intruded and I'm debating what to attribute the great response to.

Nick

I have a thermostat on mine. When the temperature reaches 90, the fog comes on until it drops below 90. I have three sections in the greenhouse. 1. Daily water and fog cooling. 2. daily watering. 3. Neither, gets hand watered twice a week. All my plants are water loving (sphagnum) or mounted or potted in rock.

A significant portion of my orchids in the greenhouse are mounted bare root or in empty wood baskets.
In the summer, the greenhouse has misters that are hooked up to a timer. 2 minute runs every 30 minutes from 10:00AM to 5:00PM. This cools down the GH and provides humidity to the plants.
This portion of southern California never sees any clouds in spring or summer so we are exposed to maximum daylight and heat.
And I dont think I had to water more frequently than last year. We are still getting the same 110F summer every year :)

Plant growth is limited by the least available factor. Given that your plants already receive sufficient sunlight, air flow and fertilizers, it was probably the additional water that allowed it to push bigger growths than it previously had.
Plants can only synthesize so much from sunlight, air and fertilizers before it runs out of water to "burn" and must be replenished.

This brings up a related question that I've wondered about: How quickly do orchid roots absorb water? I water the mounted orchids in my greenhouse in the morning as temperatures are starting to rise, so that the roots don't dry off for about an hour or so. I vary the time depending on the expected weather conditions for the day. I would guess that watering later in the day when temperatures are much higher would be much less effective, since the roots would have very little time to absorb any before it all evaporated.

Nick, I go with the higher light- it is a great stimulant( I think I am sounding like Howard!). Your plants responded well to 'more sun' and you nourished it with water. I see a whole lot of change in some of my plants after we moved to this house with lot more land space- i.e more space/ super sun light for 'chids. In the last 2 years, some of the catt/Schom and oncidium pbs are 1 1/2 thicker( and a lot more spikes) than what the plants did for 5+ years before that. My plant culture has not changed( including watering/fertlizing- they all get fed at random when I find time during the weekends>)
Infact, the one of the mttsa pbs is so fat, it looks like some other species, lol

The control on this will happen in July to October. During this time there is not a cloud on the sky and the plants growing their new leads at that time will get the same amount of sun as they received during the last number of years. This year they will get more water which will then be the only change. If their bulb size is the same as last year then the sun gets the nod. If despite similar sun they also increase their growth size then maybe water does have something to do with it. I won't know until the fall.

Nick

Interesting post. I believe the answer to your question relates to the overall efficiency of the water delivery system as it relates to a given set of conditions, given good light.

My potted catts under HID light putzed along for years until I moved them to sphagnum. It's not that the roots love sphagnum so much (I believe) but the improvement in the water delivery system given my rather warm, dry conditions. Naturally plants can put on healthier growths when the plant can make maximum use of the light it is receiving via supportive and efficiently delivered moisture. I also experienced a dramatic improvement in quality of growth and the only thing that changed was increased exposure of roots to moisture in a form that suited my other conditions. Sounds like you've hit it too.

John

I too have been thinking about water. Here in Chicago, it hasn't been as humid as usual, but it has been warm, almost California weather. I watered on Sunday three times, since it was almost 85F and unusually low humidity, say 40%. I also recently divided all my plants, and they are requiring even more water. I have a free-hanging vanda (no media) and I got so sick of bringing it to the hose or filling a bucket of water, I literally throw it into the koi pond 2-5 times a day (when I am around) to water it. Now, if my family is home when I am not, watering it is so much easier, they are willing to help. The increased light is helping, some catts are making buds, but the phals are starting to sulk a little.

Richard,

In my next life, I wanna be an orchid in your greenhouse. :)

Whitecat8