Mandevilla, Hibiscus, Aeroponics, Cloneing

Hello everyone, this is my first post here. I have recently build my DIY version of the EZ Cloner. I am wanting to clone Mandevilla, and my hibiscus tree. Last summer I tried many times with rooting powder and soil and could NEVER get anything to root. Now I built the aero machine and ordered Clonex rooting gel, and also bought some Rock wool plugs a PH test kit etc.... The Aero has been running for around five days or so but it's not looking good, :( Any advice would be much appreciated and what is the proper war to clone a Mandevilla?