# Dew indoors????

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Iv just made the Strangest observation during an experiment Im conducting that Has nothing to do with what Iv seen.

Look at the very Tips of the plants in these pics:

now I can Assure everyone that these have Never been outside, it doesnt rain in the lab and the Relative Humidity is that of any other ordinary indoor room ~40-60% and the temp hasnt been below 18c.

these plants are Wheat in one beaker and Barley in the other.

can Anyone explain these liquid droplets on the tips of the blades?

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Well I know that dew is due to transpiration (the release of water in form of steam)!

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well Im calling it "Dew" because thats what it resembles, the sort you get on the tips of grass 1st thing on a spring morning.

The PH tests perfectly neutral and its quite clear as a liquid and not as all viscous.

but Im Fairly sure "Dew" cannot or doesnt occur indoors (I think).

it seems I could be Wrong???

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My mother runs a store where she sells flowers and other beautiful plants. I just ran to ask her if there has ever been a case when you could see dew to the flowers (indoors), and she said yes (several times), but not often though.

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I wonder how that works then?

I can honestly say there have been NO wild or rapid temperature fluctuations in here since these were planted 4 days ago, and Iv done nothing strange to them yet either.

they are in ordinary potting compost with a 1cm layer of silver sand at the bottom of the beaker.

theres no excess water, and their light source (other than ambient) is a 20W Halogen bulb, they get 8 hours "sleep" in total dark at night.

and I thought I could understand it at 1st when the shoots were in the Hollow straw stage, but this is on open and flas blades now and sometimes on the back of the blades, so that rules out capillary action.

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Well honestly I don't know how it works, but I'll do some research and if I find something I'll get back.

Cheers,

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well Iv just put in a .5mm SC hypodermic needle in there as well as a 50 micron glass fiber in there, maybe the same thing will happen on the tips of these?

also, I did an evaporation test and it leaves no residue, so I tasted it and it seems to be plain water.

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I didn't really really understand this, but there's something about "dew temperature" and the whole stuff is about indoors. Maybe there's something that might explain what you have noticed.

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BINGO! found it!

or Rather my Friend Glyn found it for me (hes my neighbor at the gardens and also an ex-Chem teacher).

its called "guttation"

most notably it says at the bottom of the article: "Guttation is not to be confused with dew, which condenses from the atmosphere onto the plant surface."

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You can get dew (water condensing on a surface) indoors — it happens a lot if you run the shower; relative humidity and dewpoint temperature are related to each other. And when the surface has a high heat conductivity and heat capacity, you can remove the latent heat quite readily.

But that doesn't mean that's what is going on here. It probably isn't.

The presence of water at the tips but not the rest of the stalk suggests it's not dew (or not entirely dew). I suspect it's biology and not physics.

AHA!: Guttation

http://en.wikipedia.org/wiki/Guttation

http://sparkleberrysprings.com/v-web/b2/?p=526

Learned something new!

(technically there is some physics going on with the capillary action drawing the water up, etc. but it's still biology overall)

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neat! mystery Solved, Thanks everyone!

I shall now return to the Previously scheduled Program and carry on with my Experiment (a new Plant-food formula Iv made).

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Ah yes, the hydrothodes. Cool.

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