Cuttings in water, I have close to 100% strike rate.
how warm are we talking?
I take a cut at a leaf node,
scrape off the base by putting the stem between my thumb and scissors,
dip it in Stim-Root,
then stick it in a hydrated jiffy plug.
Works for me. I did a couple hundred like that this season.
Temperature totally! I run my aero cloner 24/7 with it off long enough to clean it/change the reservoir. I have found I get 100% success if the temp is cool enough. If it’s too hot then you get no roots or loose the ones you had. I have grown a plant from the ez cloner to completion for fun and just like with deck or nft temperature matters anytime roots are in straight water. I ran a table with hydroton flood and drain except I let it pump 24/7 while lights on and I had good success with the chiller keeping the reservoirs at 64 degrees Fahrenheit. Was an experiment, it works as long as it’s cool enough. Alternatively you can get a timer for so many minutes off and then on etc..