OrchidSafari ARCHIVES*

Members present 16:

eml729 - Eddie in Brooklyn
marylois - Lois in NW LA
uncleearl - Earl in N Calif
peterlin -Peter in Texas
marilyninOttawa - speaks for herself
Ellen,Smithtown,NewYork
gaillevy - Gail in Boca Raton FL
Fleur - in Tasmania
bmtorchids Barbara - in N Calif
JCY8S - John in S. Calif
sparkysteve, in from Cancun Mexico!
evlyn - Evie in NW LA
SD90MAC - Bob in Mississippi
Josh - in Iowa
RunnerRick - Rick in N Calif
KB Barrett - Kathy in N Calif
marilyninOttawa
I began growing orchids in the warm, sunny Caribbean in 1970. I, like any novice, looked and dreamed and consulted catalogues and bought, not what would grow best under those conditions but what I thought would grow best - but of course most of those plants couldn't thrive under warm conditions and didn't survive. I learned fast however and so am ready and able to discuss warm-growing orchids as a topic. After all, we all want our 'dreams' to come true!

Ellen,Smithtown,NewYork
Marilyn, do you grow in a greenhouse or under lights?

marilyninOttawa
In Canada, I grow outdoors in the summer and under lights, indoors of course, in the winter. In the Caribbean, I grew everything outdoors in a shadehouse.

Fleur (Tasmania)
What can you grow in the caribbean?

marilyninOttawa
The Barbados, West Indies, climate is decidely like that of parts of North Queensland. Some of most successful orchids I grew in Barbados were Dendrobiums such as the tall cane New Guinea species and hybrids. These are sun-, heat- and even salt-tolerant (D. dicolor). They can be grown in full sun. Of course, many Vandas, Ascocendas, Arandas, and allied vandaceous intergenerics grow well too! One provides shade according to the leaf shape. Strap-leaf types need more shade while terete-leaf types tolerate more sun.

Fleur (Tasmania)
So a good climate for Australasian Orchids. Interesting.

marilyninOttawa
Orchids tolerate heat but even those growing in hot climates benefit from some relief from excessive heat. Relief may be had from dappled shade of high overhead tree branches or from having roots meandering through mossy branches where it is cooler.

Ellen,Smithtown,NewYork
Marilyn, what do you do with the vandas in the winter in Canada?

marilyninOttawa
My strategy for growing Vandas in the North is to choose compact ones such as V. tesselata or hybrids of V. coerulea as the latter tolerate the cooler temps and actually bloom better under cooler conditions. Of course not all hybrids behave the same and some experimentation is needed.

gaillevy ( Boca Raton, Fl)
I have a bunch of terete vandas blooming up a storm right now and we've been breaking heat records every day.

Ellen,Smithtown,NewYork I find they are fine until winter then I must get water in the fans and they lose the bottom leaves.

bmtorchids (Barbara, from No.Calif.)
Ellen, what do you mean by 'get water in the fans'?

Ellen,Smithtown,NewYork
When I water, spray, etc., they must hold water where the leaves attach to the stem. Then I'm in trouble.

marilyninOttawa
Ellen, if you are talking about Vandas then I understand what you mean about water getting trapped. It also happens with Phals and Paphs. I water my plants with a sprayer/hose in winter yet have never had the problem you cite. I wonder if the temperature is a bit too cold for the plant's liking and this is contributing to the disease problem?

Ellen,Smithtown,NewYork
I'm sure you are right because I grow mostly cool orchids because of heating costs. Long Island is the highest in the country.

eml729 (eddie in Brooklyn, NY)
I find I must be extra careful about the time of day when watering in winter.

marylois
Long ago, I read where 1 tsp of Captan in the crown of a vanda in rainy climes will cause it to drip down as it rains and prevent crown rot.

eml729 (eddie in Brooklyn, NY)
Any surfactant should help there, Marylois. Breaks the surface tension of the water so it will flow better.

Fleur (Tasmania)
What is Captan? Soap? marylois Captan is a fungicide. Tenille is a fungus. *G*

bmtorchids (Barbara, from No.Calif.)
What is your weather condition now, Marilyn?

marilyninOttawa
Last week, our weather in the Ottawa area was decidedly hot, over 100F if you considered the Humidex. There were thunderstorms every day, culminating two days ago with one inch hail and pouring rain. Now it is cooler (65F) but should be hotter again tomorrow. I find it actually hotter here than in Barbados at this time of year.

Each island in the Caribbean has a somewhat different climate. Some islands are drier than others although for someone from a colder climate, it is uniformly hot. Larger islands like Jamaica have mountains where the temperature can be much cooler but without frost. Barbados is moderately hot and humid. Grenada and other islands such as St. Lucia and Martinique are hotter and more humid.

bmtorchids (Barbara, from No.Calif.)
Marilyn, we were in the Caribbean several times for vacation, too bad at that time I didn't know anything about Orchids.

gaillevy ( Boca Raton, Fl)
Marilyn, you must have had to water pretty often in that situation.

How is that area for humidty? Is it similar to our climate in So. Florida?

marilyninOttawa
The trick in very hot weather is to mist/spray frequently rather than to occasionally water. The plants get wet enough. To monitor the temperature of the plants, I hold the leaves as this gives me a good measure of just how hot the plants have become.

bmtorchids (Barbara, from No.Calif.)
Marilyn, I have about 35 Vandas, it's been doing great. Until this winter, or even now, all the rain and cold, Now I lost about 5 of them. Weather is very crucial I think.

JCY8S (John in Arcadia, CA)
Marilyn - have you tried Vanda roeblingiana? It has the most beautiful fringed lip - unfortunately highly recessive. My cross with it showed no fringe at all.

marilyninOttawa
No John, I haven't tried that species or its hybrids. I only grow a few Vanda types up north - space is the problems.

JCY8S (John in Arcadia, CA)
Yes, space would be a problem with Vandas. I mentioned it because it is one of the smaller growing vandas - about 12 -18 inches across and blooms when about 10 inches high. I got an award on one years ago that was only 12 inches high and about the same across the leaves.

marilyninOttawa
I will have to look for it, John.

Fleur (Tasmania)
Marilyn, now that you are in Canada what do you grow? Did you have to do a complete change.

marilyninOttawa
Well Fleur, it was interesting to learn what would and would not grow well when transferred here (to Canada). Some Phals that would never bloom in the Caribbean bloomed here shortly after the move. This could be because of the greater day length differential (16 hours/8 hours - summer/winter in Canada vs 12 hour day/night closer to the equator) or because of the lower night temperature in the Canadian situation (most nights). In Barbados, the night temperature rarely drops below 68F.

Some warmth-loving plants were difficult to maintain in winter. These I gave away before they met their demise. One favorite, a Schombocattleya, does just as well here as in Barbados, even under artificial lighting. I left most of my larger Dendrobiums there. I do not have the space!

bmtorchids (Barbara, from No.Calif.)
I can't imagine the shock of your plants when you moved. From all year around warm to the cold ice.

Fleur (Tasmania)
What would you say had no trouble or enjoyed the move?

marilyninOttawa
100% of the Phals: 50% of the others including Paph. Puddle, various Oncidiums and Brazilian Miltonias. I left some of my favorites there including those established on trees.

The plants were moved in winter, in styrofoam boxes, by air. Of course, they were accompanied by the appropriate documentation. They were first grown indoors where it was reasonably warm (70F). The major shock was humidity or more correctly, lack of humidity. Heated homes are dry in winter. especially when it is very cold outdoors.

Fleur (Tasmania)
Obviously Canada is NOT the frozen waste we see on TV. *grin*

marilyninOttawa
Well, Fleur, if you had been here in January when 6-8 inches of ice coated everything, you might reconsider.

Fleur (Tasmania)
COLD, Brrrrrrrrr

marilyninOttawa
I bought a Renanthera monachica seedling two years ago. This warmth-loving species is a darling and is now in glorious bloom. It is compact and just loves the heat. I think that Renantheras might be a good choice for hot growing areas anywhere.

gaillevy ( Boca Raton, Fl)
Some of my dendrobes are getting so tall, I'm not so sure what to do with them either, they love this humidity and I guess the heat's alright too.

marilyninOttawa
You cannot beat hybrids of Den. discolor or of Den. ostrinoglossum. Just watch that you do not change the stem aspect to the direction of the sun. These plants rely on upper leaves shading lower ones. Also, when leaf pairs are all at different angles, the beautiful plant symmetry is spoiled.

marilyninOttawa
I believe that it is a real challenge to grow orchids where the temperature is high year round, especially if the humidity is high as well. If it is hot and dry one can mist and get considerable evaporative cooling, as much as 20 degrees of cooling at 30 percent Relative Humidity. Humid air is saturated so the cooling effect is diminished. The only hope is to provide shade and air movement and of course, to grow heat-toerant orchids.

Ellen,Smithtown,NewYork
Marilyn, which warm orchids can tolerate cooler conditions? The Angraceums seem to do just fine. Are there others? Even the Arandas do better than the vandas or ascocendas. I have a semi-terete that blooms 4 times a year with a night temp. of 57. How cool can nights be for vandas and ascocendas?

marilyninOttawa
Ellen, I think that you should be satisfied with that blooming record. I wouldn't advise pushing the night temperature much lower, especially with hybrids having a good dose of V. sanderiana in the parentage. This is a plant of the hot, humid lowlands. My V. tesselata has been hit by frost once when I was out of town. This freak autumn event caused the plant to lose a few top leaves but the rest of the plant survived without noticable damage although it must have been chilled to within a few degrees of freezing. Growing plants cold night and day will cause them to stop growing and make them potentially more susceptible to disease.

marylois
Amen, Marilyn - in hot and humid we still use the evapcooler - generally an entire cool wall...beats nothing at all.

Evlyn
Since it was 103 here today.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Marilyn, I cannot believe that you say that low humidity and high temps can be good. Yes, you are right the swamp cooler works well but, the need to humidify challenges the best of us. You will see when you come here next week. The climate that you have described is the SF bay area inland. Orchids can take heat better with high humidity. Is that different from what you have learned?

marilyninOttawa
Rick. I didn't say that high temps and low humidity are best for orchids, I said that one could get better evaporative cooling under low relative humidity conditions.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Ah, thank you for the clarification. Yes, under those conditions the evaporative cooler does work well but, as I've learned, it really doesn't keep things as cool as the orchids would like. Proper humidification of the air without wetting he orchids in a small greenhouse is quite a challenge!

bmtorchids (Barbara, from No.Calif.)
Rick, you need to get a bigger cooler, my GH is bigger then yours, I have a big cooler the temp. inside never goes higher then 85.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Barbara, you are probably right. A bigger cooler would be better. Actually a wet wall would be the best but my greenhouse is too small for that. Right now, I think that I've got about the right formula... that is, it seems to work and the plants are relatively happy.

kb barrett (Kathy in N Calif)
Marilyn, when you speak of high temps you're speaking of high summer temps, and when speaking of cool, you're speaking of cool winter temps, or are you speaking of all time temps? ie don't let cool growers get over 75 in summer, etc?

marilyninOttawa
Kathy. We have different scenarios. 80-100 degrees year round as in the Caribbean; high temperature during one season and cool temperature during another season as in parts of Africa, the Himalayas, parts of North America; and cool (40-60 degrees) year round as in Columbia. Each of these environments will be suitable to a particular set of orchids grown outdoors.

Ellen,Smithtown,NewYork
Marilyn, when the plants get leggy, do you cut the top and repot?

marilyninOttawa
Ellen, make a Vanda top cutting having two or three good roots. Keep the lower stem which may develop keikis.

kb barrett (Kathy in N Calif)
As long as we're talking temps, I'm considering getting a Cytrochilum macranthum. Native to the Andes in Ecuador??? Columbia??? One of them. They were profiled in the January 'Orchids' as cool growers, but a fellow grows them outdoors in San Diego (inland - not on the beach) so I was tempted to try it, If I keep the thing misted in the summer (evap cooling) it should be able to grow outside here (38-40F lowest in winter). Or at least that's what I hope.

marilyninOttawa
Keep us posted Kathy. I do not have any experience with that orchid.

Tex1 Dan (Dan from Wharton,Texas)
I'm trying to finish my last couple of purchases for my greenhouse. Ed's talked me in to buying a water softener and use KCL...Can anybody recommend a brand a type. Also....I'm wondering what types of heaters can be used. Are there any different ones beside the Modine style heater?

kb barrett (Kathy in N Calif)
Marilyn, does airlayering work on Vandaceous plants? I'm trying it on 2 that I almost killed. They dehydrated, went limp, lost their roots. Now I'm trying air layering for new roots.

Evlyn
I've heard that hanging a vanda upside down might help Kathy--never tried it myself.

Fleur (Tasmania)
Evlyn, not sure about Vandas but some of my sarks [sarcochilus --kb] are mounted upside down and are doing well.

kb barrett (Kathy in N Calif)
That's right, Evie! I forgot about that trick, tho' I did try it once with no good luck. Barbara has tried it, but I can't recall how it turned out for her.

bmtorchids (Barbara, from No.Calif.)
Evlyn, that doesn't work, unless you have soak it in the 10% bleach like Ed said.

SD90MAC (Bob-Ms.)
Would you believe that my Ascda. that was awarded in 1982, froze in 1994, has come BACK from the DEAD. It is actually blooming!!!!!!

marilyninOttawa
Kathy, you might try removing the dead leaf bases to the stem to expose dormant axillary buds then apply rooting hormone to stimulate root development. One of the lanolin base pastes is good. Another alternative is to place the plant with a little damp moss in a clear plastic bag. Hang in a shady area out of direct sun. Open the bag daily. Rooting will be possible in 4-6 weeks.

Evlyn
Another option would be water culture, Kathy.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Evlyn, I've tried it and it does work - very well. I nearly lost a big renanthera and it is now nearly all back with LOTS of roots.

marilyninOttawa
Wetting the orchids in a breezy environment causes evaporative cooling of the orchid plant. We found a profound effect when we tested the process in the lab, using a sensor inserted into the succulent leaf tissue. 10 F cooling was possible in a matter of minutes!

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Marilyn, it may cause cooling but it also causes leaf spots. There are better ways and I know that you are not saying just to wet down the orchids in the heat. You are right, misting will help a lot!

Ellen,Smithtown,NewYork
Do warm orchids need more fertilizer because of the higher temp. and light?

marilyninOttawa
If orchids are exposed to more light than they can use or to higher temperatures than they can physiologically manage, more fertilizer is not necessary. In fact, orchids may stop growing under such conditions so fertilizer application should be discontinued. During our recent hot spell when temps were up to 100F in the greenhouse, I discontinued fertilizer application and concentrated on getting the temperature down. Humidity was high so evaporative cooling was a challenge. Still, I could achieve about a 10 degree drop. My cool growing orchids were taken out of the house and placed in deeper shade. They were supplied lots of rainwater so that they could replace what might be lost by transpiration. Masdevallias and Disas cool themselves this way. Succulent orchids hunker down by day and will not absorb or lose significant amounts of water.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
I think that if serious cooling is needed, with preservation of humidity, then heat transfer is the only way by spraying the air with fairly heavy droplets of cool water. The heat transfer will provide the effect needed. Evlyn
Heavy droplets???----not a good thing.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Evlyn, the best place to have the heavy droplets is in a box of some sort. The idea is to have a fan blow the air through a box that has an exit filter that traps water droplets. Inside the box is a set of sprayers that spray cold water into the air. This will cool the air and output no water.

kb barrett (Kathy in Calif)
Rick, wouldn't an evaporative cooler be almost the same thing? Of course the box would be cheaper.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Kathy, yes, that is an evaporative cooler with a slight twist. The evaporative cooler works when the ambient humidity is low so that the incoming air will supply the 440 calories of heat per gram of water to evaporate it. When inside and the humidity is high, that won't happen so we have to go to the 1 calorie per gram per degree cooling that cold water brings --- but we spray a lot more cold water.

marylois (Northwest Louisiana)
Where does one get cold water in a heat wave?

kb barrett (Kathy in N Calif)
Rick, so the cold water cools the air and the big drops don't escape the box to cause leaf spots, got it.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Lois, the idea that I had for cold water was to put a tank in the ground. The ground tends to stay pretty cool - about 55 degrees F. That might work.

marylois (Northwest Louisiana)
Yes, Rick - might. Would have to go mighty deep here...my water is like bathtub water...no matter how long I let it run. They don't go down very deep here cause no worry about frostline...get down a foot or two, and they are okay.

kb barrett (Kathy in N Calif)
Rick, Probably would help in heating in the winter too, keep it 55 instead of 38.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Lois, I would have to re-engineer the idea for your location. This design is what I came up with for my greenhouse and ... it worked.

RunnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Kathy, that would be true. City water could be a backup for a down heater in an emergency in the winter as the temp here tends to stay fairly constant in winter - as long as the water has been in the ground. Once out in the air, it is as cold as the air.

marilyninOttawa
Those of us having cool/cold seasons will have access to cool water but those in warmer climes will not.

kb barrett (Kathy in N Calif)
One of the guys here has a couple of humidistats and timers linked together. It works that the humidistat senses the low humidity and turns on the misters for 7 seconds. Then if the humidity is still low it will turn the misters on for 7 seconds again. He says that keeps the leaves from getting soaked/spotted. Works for him...

marylois (Northwest Louisiana)
I poured and fired a porcelain pot - about 10" sq (oval), but flat - you know, boat-shape opening....attached an Epc Vienna Woods...has taken forever for it to really get going, but it is flourishing! You keep pot filled with water and you get cooling through to the roots on the outside - attached it as a wee seedling. Pictorial Description

Fleur (Tasmania)
What a wonderful idea.

marylois (Northwest Louisiana)

Really quite neat - cut four holes at top, threaded thru nylon roping - looks good hanging up there. Gonna make a few more for those Paraphal babies in a shared flask at this time.

Fleur (Tasmania)
It would be great for some of the sarcs that like to ramble. I wet the floor to increase humidity, works well.

Evlyn
Got a picture of what you are describing Lois--I'm not getting it.

marilyninOttawa
In the tropics, we grow Vandas and other tall growing Vandaceous intergenerics mounted on pieces of clay drainage tile. The bottoms are sealed and the centers filled with water. The roots love the damp., cool surface and the plants thrive.

kb barrett (Kathy in N Calif)
Fleur, does damping down the floor reduce temps in addition to increasing humidity?

Fleur (Tasmania)
It reduces the temp by quite a bit in summer, even in a shadehouse.

marylois (Northwest Louisiana)
I'll take pictures soon as I get a new battery for the DC-40. Fleur - been thinking of attaching Den. kingianum to one.

marylois (Northwest Louisiana)
That's exactly why I made the porcelain pots, Marilyn - same concept...unglazed porcelain ceramic. kb barrett (Kathy in N Calif)
I know American Indians used very tightly woven baskets to carry their water, the evaoration through the weave kept the water cool...

Fleur (Tasmania)
Kathy, a similar system is still used here in the outback, a canvas bag of water is hung from the front of the jeep, water is kept cool.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Marilyn, that sounds like a great idea! Drainage tiles ie: small clay tile pipe that is somewhat porous... this could be an idea...

Fleur (Tasmania)
Not sure about the Kingianum Lois, they keep their roots in the mix. But would look stunning if it worked. runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Lois, was that porcelain just bisque fired or was it vitreous?

marylois (Northwest Louisiana)
Thought I'd make a sphagnum padding tied on with filament thread first - then a kingianum keiki - worth the experiment. Now! Just find the time to get back to the ceramic shop...and hope they still have that mold.

It was porcelain bisque - fired, but not glazed. I had some pipe - but most of it is asbestos, so I dumped it...the pipe looks fantastic with Chinese cyms in it though. Just afraid of it.

Fleur (Tasmania)
You can buy clay pipes here, diameter about 8 inches length about three feet.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
I'm sorry, Lois. Not all asbestos was bad, just the kind that shed particulates . Oh well.

marylois (Northwest Louisiana)
Should work, fleur - just be sure they aren't lined with asbestos. Plants might not mind, but you would.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Fleur, be sure that the pipe is semi-permeable at least. Vitreous clay is of no use as it is entirely waterproof. Fleur (Tasmania)
No asbestos Lois, just terracotta pipes.

runnerRick (Rick in Concord, CA. Diablo View OS, AOS)
Lois, did you do your own firing on that dish?

marylois (Northwest Louisiana)
That old asbestos pipe sure looked like a shedder.

kb barrett (Kathy in N Calif)
Sounds like a source of income for Lois! I suggest the tradename 'Marylois Mania'

marilyninOttawa
The clay must be unglazed. This works well with certain Masdevallias. the clay pots are always cooler.

marylois (Northwest Louisiana)
Fired at the base ceramic shop at porcelain temps...walls are only 1/8" thick.

Fleur (Tasmania) The pipes I am talking about are made the same as the terracotta pots.

marylois (Northwest Louisiana)
Should work, Fleur - figure out a way to seal the bottom...AND when algae builds up in pot, it flows over plant roots when you water - I make sure I add lots of water with each watering to prevent to great a buildup.

kb barrett (Kathy in N Calif)
Marilyn, why place only the cool growers outside in deep shade? Why not all orchids, after all the ambient temp was 100, probably hotter and closer in the basement than outside under a tree.

marilyninOttawa
Exactly, Fleur.

Fleur (Tasmania)
I will give it a go in summer/spring when I start re-potting.

marilyninOttawa
Actually Kathy, I do move some trays to lower shelves but moving the entire collection is just too much. Our hot, humid spells last a few days and then it is a week of cool rain, and then maybe hot and dry. I understand about leaf spots, particularly on Phals and Catasetums so these I grow elsewhere. My Cymbidiums are in full sun in the herb garden, the Oncidium and Cattleyas are in the upper levels of the greenhouse while the Sarcos and masdevallias are near the damp floor.

kb barrett (Kathy in N Calif)
Marilyn, got ya.

marilyninOttawa
Well, the Canada Day fireworks are underway and so I am going to go and take a peek. What I can see from my window is spectacular! Twas a pleasure chatting with you all this evening. See some of you soon. Until the next session - any suggestions??

Fleur
Thank you, Marilyn, for a good session.

marylois (Northwest Louisiana)
Yes - as always, Marilyn - maybe the minis next time?

marilyninOttawa
Those adorable minis it is - Lois!