Orchids and Temperatures

[monivik]

So I was just wondering if there are any tips and tricks for just the ordinary home-grower on how to deal with extreme situations like a heat wave.

It's extremely hot here right now, I'm talking about +30 degrees C, which is like 86F... yeah and the temperature is rising. Unfortunately I can't afford an air-conditioner and my small apartment is at the moment unbearably hot... I've just got regular fans available.

Now I was just wondering in such extreme heat situations what would you advice on the care of orchids. I've got a number of Phalaenopsis orchids that I've just repotted and they weren't looking too great to start with, they're recovering. I've got three recovering Brassias too, not many roots there.

I've also got a Paphiopedilum (it's green leafed, not motted) which is in bloom right now. I've got an oncidium and an oncidium something hybrid and a Miltoniaopsis in full bloom.

Should I water more often? I keep spraying the Miltoniaopsis for moisture, is this ok?

Also the Brassias I've got them with spaghnum moss around them, as they don't have many roots...for humitidy.

[Ray]

Deep shade to avoid further heating.

Phalaenopsis will LOVE it, miltoniopsis will not. Others will tolerate it.

Plant metabolism increase with temperature, so keep up with the watering without drowning the roots.

[Roberta]

A trick that I have used for orchids that hate heat (like Masdevallias, for instance) - clay pot with spaghnum, kept pretty wet - evaporative cooling of the roots does help. You can even put that clay pot into a larger clay pot, with or without sphaghnum in the space to enhance the effect. (Just remember to remove the extra pot if it turns cold and is staying too wet)

[camille1585]

During last summer's heat wave from hell (I'm also in the Netherlands), I was surprised by how well my orchids coped. All the warm loving plants, like Phals, flourished and were growing like crazy. It helps that we don't get excessively dry heat here. The few orchids I had which prefer cooler temps suffered tremendously since the heat lasted far too long. The clay pot and sphag tip is a good one.

For all orchids, you will have to water more often since they dry out faster, but taking care not to overdo it either.

My apartment gets really really hot during a heat wave (usually it's at least 30C) since all the windows face south. I moved a lot of the more sensitive orchids outside onto the shaded part of the balcony, so that they could at least have cooler nights than they would indoors. Indoors, I moved my orchid shelves away from the windows.

I'm really happy that temps are back to normal today!

[monivik]

Thank you all for your replies. I think it's worth thinking about the clay pot and spaghnum moss for the Miltoniopsis, I heard someone say that once before. However she's in full bloom right now, I'm not sure I want to repot her right now. Her roots look nice and green so far though, the ones that are close to the top. I keep spraying it with water, I also keep checking with a skewer to see when I need to water it.

I'm glad to hear that the temperature is not a problem with the other orchids. I will indeed keep a close eye on when to water. I've got all my Phal's on clear pots with air holes. Most of them (except one) are actually looking good, lots of new roots in the making.

I think keeping them away from the window is a good idea. I've indeed only got windows on two sides, one side the sun shines all morning, the other side it shines from about 4 p.m. until sun-down. So away from the windows for now.

[rbarata]

My orchids have been copping with heat without any problems. By heat I mean everything between 35 and 40ºC, which is the normal range for summer temps around here. Last year we reached 45ºC and none of my orchids had any issues, even those outside. Temps inside were between 28 and 30ºC.
My collection ranges from cymbs, paph (green leaves like yours), Catts, Laelias, Phals, Onc, Bletillas, Stanhopeas, Pleiones, Miltassia, Coelogyne, etc.
As you can, for half of it, these summer temps are out of their range but none of them had any issues.

As sugested, keep them away from the windows, water more frequently and, if possible, get one of those fog machines. Air energy (manifested in the form of temperature) will be spent to evaporate the micro water drops of the fog, cooling the environment. I got one for 20 € and it makes wonders.

[cluelessmidwesterner]

I'm so glad you asked this question. I live in the states and we've had a very cool wet or overcast spring until this weekend when it went from that type of weather to heat plus high humidity (think tropical dew points). Presently for the warm months I've moved my S/H plants from indoors to a screen porch shaded from the West and SW corner by mature maples. The plant's get very late afternoon (after 1700 CST) sun. Is there any else I should do for them?

[rbarata]

The sun at 17:00 is still too strong around here. Iowa latitude is approx. the same as mine so be carefull.