I would think the dew helps but it is not sufficient to make up for the lack of rain. If your plants wilt, you will know that they need more water.

well, the dew eventually drips off onto the ground around the plants. I always turn my irrigation system off around the begginning of November and I don't turn it back on until April or May. Natives and near-natives (plants from areas with similar climates) can survive with what nature gives them. Take into consideration though, that i live in the San Joaquin Valley and we get a lot of overcast and foggy days during the winter season. When we get fog, we get dew dripping from all of the plants all day long, and the ground remains moist. Here's a photo from a couple of weeks ago. Look at how green everything is! (forgive the poor quality, it was taken with my phone)

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I think if you've had a good, soaking rain, and the temps. have remained coolish (60 or below), then the dew would coat plants with moisture, drip into the ground, and be the first moisture to evaporate on a sunny day, keeping the moisture in the lower levels...if that makes any sense...and that would mean, that, yes, the dew is making a difference.

wanda

The coast redwood forests along the California coast get about 10 inches of moisture from the summertime fogs we all complain about. In the winter when we go for days with no rain but a humidity of 95% there is very little evaporation to remove what moisture we have. Al

I did a little research and it appears the wheel I proposed has already been invented.

Here is a link that might be useful: Dew harvesting in India

Plants in Chile's Atacama Desert depend upon fog and dew for survival. There is virtually no rainfall there, the driest area on the planet.

RB

Many native California plants subsist on fog and dew for moisture. The dew collects on the leaves and drips to the ground. Furthermore, many native species usually go dormant during the summer or don't like summer watering (only if if gets too dry, do you water.) But your tropicals and moisture loving plants will have a hard time this summer if we don't get rain, and if there will be mandatory water rationing. I live in Long Beach and we have mandatory water rationing. The dog day of summer, I let my lawn go brown. Right now it's green (Bermuda grass) because of our last rain. But in the backyard, I pulled out much of the lawn and used ther area for planting more drought tolerant native plants.

I guess I wasn't clear in my question. It should of read can most plants absorb and utilize water directly through their leaves from dew? I am not talking about water from dew that drips off the leaves onto the ground and is then absorbed through the roots like rain would.
I guess the answer is yes since foliar feeding applies the liquid fertilizer directly to the leaves, so dew should also be absorbed.

Hmm collecting Dew is like trying to squeeze the humidity out of the air and that gave me a weird idea but why not try placing a good dehumudifier outside to collect the humidity? Or maybe this would be the beinning of a good idea to make a device that can withstand the harsh elements and squeeze out the humidity from the air... People use these devices to collect " unwanted humidity" from the inside of their house to prevent mold... I know this really sounds far fetched but "just a thought" lol...Dehumidifiers are not known to be very energy efficient but there are some models that carry the energy star..

I always believed that dew causes fungal diseases, by wetting the leaves, yet not being enough to water the roots, and therefore was a negative thing. I had some CA poppies that got grey mildrew. There were the not orange ones, but like other mixed colors such as pink, and white or yellows. They then died pronto.