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Location

Message

Date Posted

Scranton, Pa

I know below 55 is where growth starts to slow at night but what high temp do you start to see the kin start to slow down from excessive heat?

7/30/2019 11:03:40 AM

San Diego, Ca.

I think it depends on the characteristics of each plant regarding how well it handles the heat. I've had plants that 110° didn't even make a difference in growth and other plants that 110° was a problem for. Gotta keep the water going to them when its that hot!

7/30/2019 8:59:57 PM

Lloydminster/AB

I think it’s leaf temperature that you have to measure. Some where around 27°C is where my plants try to maintain themselves. It seems quite independent on air temp. Sometimes I have wilting leaves at 28 and some of my plants will go much higher than that with no wilting. Research I’ve read says that photosynthetic enzymes start breaking down at 27, unless you are adding co2 which overrides the breakdown a bit. Look up co2 and leaf temperature. I’m still reading research on this. Pretty interesting.

7/30/2019 11:35:02 PM

Colorado

Pumpkins don't like it above 84 degrees so the plant isn't photosynthesizing ideally and moving liquids as efficiently above 84.

7/31/2019 5:47:55 PM

Midway, UT

John Tabenara once told me that photosynthesis stops at about 91 degrees.

8/2/2019 8:57:46 AM

Torrance, Ca.

John T know his stuff!

And Don Crews is right, with co2 added the plants can thrive in much warmer temps.

8/13/2019 12:00:43 AM