|A Begonia luxurians cutting sending out some new roots|
1 - Cut off a non-flowering growing tip of about 4" at a node.
2 - Dip the cut end in rooting hormone.
3 - Place the cutting in a seed tray using a 50/50 peat/pearlite mix (or any sterilized potting mix).
4 - Create a humid environment for your rootless cuttings so they won't dry out. In this case, I used a large zip-lock bag.
5 - Place the cuttings on a heat mat. Yes, this step is necessary.
6 - Water them.
7 - Be patient and keep the cutting under an optimum amount of humidity (enough so they don't dry out but not so much that mold will easily grow). You can see in the picture below, I opened the ziplock bag to let some moisture out.
8 - New plants need a lot of bright, indirect light, otherwise they will wither away and die. I put them right under a giant fluorescent light and it works great.
Below are four Beschorneria yuccoides seedlings (out of several hundred seeds that I tried germinating). I took the seeds from a plant I've had growing since 2008.