Flutter log event with google analytics

I have set up Google Analytics with in my flutter app. It all seems to be working as standard, with data coming through and being displayed on the analytics console screen, showing users, events count that sort of thing.

I see the default events are: user_engagement, screen_view, session_start, first_open, app_remove, app_clear_data.

These are all having event count data coming through fine. I want to set up my own custom event within the flutter app. I have tried this...

_sendAnalyticsEvent() async {
    FirebaseAnalytics analytics = FirebaseAnalytics();

    await analytics.logEvent(
      name: "save_plant",
      parameters: <String, dynamic>{
        'plant_name': currentPlant.name,
        'plant_species': currentPlant.species,
        'plant_group': currentPlant.group,
        'new_plant': widget.newPlant
      },
    );
  }

... but nothing seems to be coming through on the events. Am I missing something here with doing custom events with a flutter app? I have the google-services.json file correctly in the android app directory.