This set of nodes is part of the node-red extension to the free, open source, SIP irrigation control software for Raspberry Pi:
These nodes allow you to easily use node-red flows to control SIP and add new features such as a simple day-night timer for landscape lighting:
up to experimental flows implementing advanced algorythms for controlling irrigation based on data from soil moisture sensors, online weather sites, a local weather station and more.
To help you get started there is an example flow for each of the nodes in this set. Some of the examples include dashboard nodes and require the dashboard nodes to be installed.
Among the advantages of using node-red flows to interact with SIP is that you can easily make changes "on the fly" while SIP is running.
For anyone wanting to dig deeper into SIP's inner workings there is also documentation for advanced users that describes how to read and write SIP's control variables from node-red.