This is to bring to your attention a blog post I wrote a few days ago, which describes how to get OpenSprinkler to work with IFTTT. With this capability you will also be able to use Amazon Echo (Alexa) to control OpenSprinkler, therefore using voice command to trigger sprinkler actions. For details please check the blog post:
https://opensprinkler.com/ifttt-with-opensprinkler-and-opengarage/