One of the biggest issues with taking plant cuttings is disease.
This tip says to use cinnamon to alleviate the chances of getting fungal infections in your cutting, improving your chances of success. Since I know that some of us are interested in rooting plants, it should be worth a try.
In other garden news, only our radishes and onions came up, all the other seeds planted in the garden were failures (save possibly a single nasturtium, but we will see with that one). Next up is transplanting our seedlings from inside, which historically has had about a 20% success rate. So we will see.