This particular plant is native to Africa, the butterfly shaped floral features seemed to be the unique feature which attracts this particular plant in cultivation as ornamental plant around the world.
Other common names include:
Blue Butterfly Bush, Blue Glory Bower & Blue Oxford Bush
The best I found is from the matured stem cuttings. They may stay dormant for weeks, then sprouts may appear from the nodes. Sometimes few of the cuttings may not survive - so it is best to have more cuttings planted than just one.
Another method is to put the cutting into perlite medium (soaked in water) Once taken roots, it should be carefully transplanted into a good potting mix..
Once they start growing - you really don't have to worry as more vines and new plants emerge from the base roots area.
One of the most challenging part for this shrub is pruning. They do grow extremely fast and become very unruly if not proper care is not given - especially when it comes to growth factor, this plant focus more on branching more stem and over growth rather than blooms which can be one of the down-side coming from this ever blooming plant.
However with the right pruning method and keeping it trimmed and manageable size - this one can be such a beauty. This plant can become into a full grown tree - hence pruning and keeping focused in making its growth into one main stem can allow it to bloom more gracefully and not creating a wild-like shrub with stem branching everywhere.
It may require a good adequate watering - both morning and evening based on the size of the plant.
You can grow it in a nice medium or large size pot, the plant will behave and grow based on the size of the pot. However I would recommend this to grow freely on ground if you want lushful beautiful constant blooms.
Also this plant is a heavy feeder and do feed adequately during the flowering season.
However if limitation occurs where you can only grow in pot - then a good balanced potting mix with rich amount of organic material and equal part of well drained soil which will help from root rot.
Do click on the link below for more detailed information on the other Clerodendrum Plants and Posts:
Different Types of Clerodendrum Plant