What to do about morning dew?
 

I was under the impression that if I kept my orchids dry, it would be okay. I put my orchids out, and immediately I realized that was going to be impossible due to dew, that even if I put them under shade cloth or a tarp, if the temperature drops below the dew point, the leaves are going to get wet. Maybe that doesn't matter much when the temperature is around 45-50 at night right now, but is this going to be a problem when the temperature drops to 37-40?

hey kat, I don't grow outside, you need the advice of a greenhouse grower but could it be the initial temp of the orchid causing the condensation?

Once the orchid is the same temp as the outdoors there will still be dew but not as much as what forms on a warm surface.

The little that does form serves to water the plant which is why outdoor growers love to stop watering completely in winter and let nature do it for them.

Which orchids are we talking about?

There are two conditions that must be met for dew to form:

1) The air must be saturated. I.e., 100% RH.
2) The temperature of the object must be lower than the saturated air, so some of that water will condense.

If the object is warmer, the air immediately around it will be warmer as well, and warmer air can hold more moisture.

I have dew on my deck right now (at dawn), but the concrete patio, which is still warm from yesterday’s sunshine, is perfectly dry.

well spotted Ray.

So then other way round to what I said but the principle remains, outdoor plants get more dew and condensation than indoor plants. Can't help with the question though

I'm with rbarata... first, what orchids? I have quite a few that would not tolerate 37-40F. Many orchids grow where the leaves get wet often, then dry off with wind, etc. I have orchids under misters that get wet leaves three times a day.

So is the theory you're working on, or have read, or been told, is that if the plant is dry it can tolerate a colder temperature?

My wife would kick my ass if my indoor plants got dew on them and dripped all over the floor!!!

Here, living 75 feet from an inland waterway, with the ocean a mile away, we often run into very high humidity early in the morning, so my plants (when outdoors) get dew on them, even when the overnight temperature is in the 60's. Within minutes of sunrise though, when the air warms, they all dry off again.

I imagine there are lots of orchids experiencing dew on a routine basis. Some of the plants that experience a "winter rest" only get their water from dew.

To me, the bottom line is "no problem".

To the original poster.

How long are they wet and do you get frost? To me, dew is not a problem while frost IS.

If they are dry in 20-30 minute after sunrise and then dry and warm all day I think that sounds lovely lol

I'm with Ray.
Our dew here is so heavy this time of year. By 9 PM you can hear it running off the metal room and dripping down the downspouts.
My orchids love it but then we don't go into the 50's let alone the 40's but I still doubt it will hurt them. They may actually love it!

Yes, it matters which plants. Go to Roberta's Web site and look at what she's growing outside. She's probably closer to the ocean than you are. She probably has temperatures like that from time to time.