time to chill Phalaenopsis

[jerrymeola]

Normal blooming season for Phals is winter. You may not realise it since they are available all year. Commercial growers heat their greenhouses during the winter and cool them later when they want to induce flowering. Phals like 45-55 degree night temperatures with 75 degree days in order to set buds.

If you grow them in a warm house, you might get better flowering if you move it to a cool (not cold) entry way, basement etc. Once buds start to form it can be moved back into its normal position.

If the temperature change will be more than 15 degrees move it over a couple of days to let the plant adjust slowly.

[Cynthia, Prescott, AZ]

Jerry, I just got the second volume (Vol.1) of Bakers hardbound book of his culture sheets on 'Pescatorea, Phaius, Phalaenopsis,...' and am reading up on Phalaenopsis. The general recommendation,applying to hybrids, not for warmer growing species, to stimulate spikes is to reduce night temp to 55-62F, and never below 52F, for about 4 weeks, with fertilizer withheld starting only during the fourth week (pots flushed to remove residual fert). Light levels are incresed a little at the beginning of this period. Apparently this is the formula that commercial growers use. What comes next seems to go off the deep end to me. As temps are returned to normal, an Epsom salts solution, 1/4 lb. per 5 gal., is applied for the next 3 to 4 weeks, then the pots are flushed for a week. Looks like higher light and otherwise no fertilizer are maintained for about 3 months. I wonder, in this formula, how important the Epsom salts is.

The caution about the warm growing species bothers me, 'some [warm] species are not healthy with continuous lows of 65F'. 65F???? I keep my bench at 61F during winter, and the plants being hung aren't getting much warmer because there is too much air mixing in my small (8X12) GH with lots of fans going. I think I will hold off on collecting more species Phals until I either get my permanent GHs in or if I can adapt a light stand I have planned for my basement for warmer temps. Cynthia

[jerrymeola]

One thing about commercial growers is that everyone has their favorite way of doing things.

Anyone giving advice tries to give the safe advice. I was somewhat reluctant to put my low at 45 degrees since this is lower than many advise, but I actually leave mine out into the high 30s. One reason is it is just impossible to control temperatures for the "perfect" situation for each orchid. Not all plants survive the lower temperatures. For commercial growing it is a trade off of losing some plants for a practical way of growing them. It also allows only the strongest plants to survive and then we are selling the best plants. I do not find my losses to be more than a few percent. I expect I would lose that many witht eh best care.

Several things are happening when orchids are subjected to lower temperatures. They use much less water. In areas like SW Florida the cool nights produce a lot of condensation. My orchids look like they were soaked with a hose overnight. I have almost stopped watering the shadehouse because the orchids look soaked every morning. Since they are using less water and getting more condensation, even no water may be over watering. They needed to be watched and watching requires experience to recognise changes.

Orchids are very strong and can take a lot of abuse. Actually abused plant often flower better. It is a survival thing. Threatened plants flower to try to reproduce before dying.

Magnesium is probably the most important trace element for any plant. In SW Florida it is a must for all plants, orchids, bushes, trees annuals, everything. Epson salt is Magnesium sulfate a very usual form.

Problems with books is that they generalise on their conditions and the 'accepted' wisdom at the time it is written. Never totally book written over ten years ago. 19th century "expert' recommendations recommended orchids in dark very high water conditions. Botanical greenhouses killed over 99% of everything imorted.

The problem with the epson salt recommendation is that, as its need became apparent, manufacturers started to put magnesium into the basic fertilizer formula. Peters, Miracle Grow and Jack's all may magnesium in the formula. Check the label on the one you use. Adding more is not necessary. But flushing after a couple of weeks prevents any overdose of magnesium to be harmless to the plants. I recommend flushing every plant not just orchids to remove buildup of slats. Our rains in SW Florida flush everything whether we want it or not. Many people still use a magnesium bath with fertilizers that include magnesium. It may help, it may do nothing, it does not seem to kill plants.

The one absolutely correct piece of advice I can give is to never trust any recommendation 100%. Even the most knowledgible experts, with them giving their best advice, may still be wrong for you.

[Cynthia, Prescott, AZ]

Another comment in the book, of note, is that cold water that is well below ambient will cause leaf pitting. This one was a biggy for me. Two winters ago, I had my 65 gal. RO water tank sitting out a ways away from the GH. I had it covered by black plastic and bubble insulation over that. This arrangement did not prevent the water from getting down into the low 40Fs as below freezing weather continued for several weeks. Since my half dozen Phals were being grown warm and cozy with good light, AZ is almost always clear, the plants suffered severe leaf tissue collapse. The plants have been reduced to seedling size and are only now starting to make good progress. I have since moved the tank next to the GH, insulated better and opened the bottom of the separator between the two to allow heating of the tank. I now get down to about 55F, and add some heat below this via a jury rigged hot water heater type heating coil. But I have still had some tissue colapse with this water, so after reading this comment, I have set aside a jug of water and a spray bottle in the GH to have ambient water for my small Phal. collection. Cynthia

[jerrymeola]

An interesting piece of information that sounds reasonable. I do not have that problem in Forida in that my well water all winter is 10-15 degrees warmer than ambient.

By the way amost 2500 parts per million of dissolved minerals in the well water does not seem to be any problem for orchids.

[Cynthia, Prescott, AZ]

Thanks for the info on your ppm, that is quite surprising, not only that your orchids can take 2500 ppm, but that anybodys well water goes that high. What is the PH of your water? I would have expected this kind of water from some of the alkaline deserts of California. Is your collection mostly Phals and how do you use the water to prevent salt build-up.? I assume you are being extra careful about that. I have been warned that Phrags like very pure water. Cynthia

[jerrymeola]

Ph runs around 7.6-7.8 but the high minerals mean any attempt to lower the ph will revert back in 10-12 hours.

I am a commercial orchid nursery and most of my plants are cats, onc types (used very broadly), dens and miscellaneous plants as they come available.

I have a few Phals in my personal coolmection and about 50 in a test growing situation. So far almost nothing I have tried kills the phals.

I do a lot of Phals for sale in hydropnics and naturally hanging plants. Phals grow naturally with the roots at the top connected to a branch and the plant and flower hanging down frm there. I will post instructions for both as soon as we get photos uploaded to the gallery.

The hanging plants look so good and natural it is easy to see why they do not like pots. when I put seedings on a mount the roots grow right up into the hanger. It appears the roots are genetically engineered to grow up.

[Cynthia, Prescott, AZ]

I have had the opposite problem, Ive killed every Phal I have ever had during the 25 years I had my GH in Calif. And I've gotten a pretty good start on the ones I have here. In Calif. I grew in a one size fits all GH. Everything got Catt light (63% shade year round) and Catt temps. It was either the high light that stressed them, or now that I think of it, maybe they needed warmer temps. At any rate, they gradually went down hill and gave up when the least problem came along. Never had a water temp problem in Calif., as there was never any tissue necrosis. The days of one size fits all are over. My Phals now hang in the shady quarter of my GH. I'm seriously thinking of putting a small electric heater in the eves of my GH, set on low, to pump up the heat near the roof. Right now there is too much air mixing to make it any warmer up there. Cynthia

[Sallyd]

I have never had a problem with the phals. spiking for me and one of the reasons I think is because I keep them outside in the fall. In PA, we have big temp. changes so that takes care of that. I do the same with my cymbidium which is in bloom now. I have 6 phals. in spike. The best thing I found for myself is the semi-hydroponics. I killed many a phal. from overwatering. They just love the s/h. My paphs. and phrags. love it, too.

[Gin]

I have more Phals. than others approx. 70 , I don't do anything special for them .
They do get a night drop in the fall , fed weekly full strength per label directions . Greenhouse Temp. is 62, Rain or RO. water MSU. Fert.
Thats it almost all are in spike some double . I think it is what ever works for you, my species Phals . are in an area closer to the heater . and do well there . Gin

[orchidaddict789]

My home gets a bit cooler during winter (always around 65 degrees at day, probably lower during the night). This sets the phals into spikes. I just noticed a little spike (I think) on one of mine though it's still a little bit early for my phals.

[Claire]

I don't have a problem getting them to spike here either. But I did have a minor hail tragedy that made the collection unhappy enough to not spike.

My Baldan's finally spiked and maybe two months after that I had another one spike. Strange, usually they all spike within the same month.

[Tommyr]

I never had luck reblooming phals so far in the 3 years I've had them. I'll have to try the temp difference thing, it works for xmas cactus for me so....

I have one phal left, got fed up with the 2-3 others that did nothing...

My Den however is budding for me!

Tom

[Cynthia, Prescott, AZ]

Tom, I have just reviewed this thread, and I see that there has been no mention of the other major trigger to blooming, and that is day length. Phals are triggered by a shortenning of day length, as well as temp drop. Have you been keeping your Phals in a room where the lights are kept on to the same time every night? I would definitely do something about the day length if you are going to try to shock this plant into blooming. How about a dark (cool?) closet, with a light on a timer set for 6 hours on? I'm sure you can find something to do. Also, I have been told that almost any stress will trigger blooming, like letting the plants dry out excessively, but be careful not to let the leaves wrinkle, as this will probably be irreversible. Good luck, Cynthia, Prescott, AZ.

[Tommyr]

Originally Posted by Cynthia, Prescott, AZ

Tom, I have just reviewed this thread, and I see that there has been no mention of the other major trigger to blooming, and that is day length. Phals are triggered by a shortenning of day length, as well as temp drop. Have you been keeping your Phals in a room where the lights are kept on to the same time every night? I would definitely do something about the day length if you are going to try to shock this plant into blooming. How about a dark (cool?) closet, with a light on a timer set for 6 hours on? I'm sure you can find something to do. Also, I have been told that almost any stress will trigger blooming, like letting the plants dry out excessively, but be careful not to let the leaves wrinkle, as this will probably be irreversible. Good luck, Cynthia, Prescott, AZ.

Thanks Cynthia, I'll try that. I'll treat it like a poinsettia I guess.

Tom