There’s a OpenSprinkler integration in HACS, as well as a OpenSprinkler card. You can search for them in HACS, but here are the repository links:
https://github.com/vinteo/hass-opensprinkler
https://github.com/rianadon/opensprinkler-card
The integration will get your HomeAssistant talking to OpenSprinkler. The card is optional, but provides a more functional UI than using built in entities.
You can start zones and programs manually from the card.
You can start zones and programs from automations with the integration itself using the opensprinkler.run_station and opensprinkler.run_program actions.
The documentation includes some good examples that should get you started, but I’m happy to help if you run into problems.